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epdc v2: improve behavior at high temperatures#1

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akemnade merged 1 commit intoakemnade:kobo/epdc-v5.13from
jetomit:kobo/epdc-v5.13
Aug 23, 2021
Merged

epdc v2: improve behavior at high temperatures#1
akemnade merged 1 commit intoakemnade:kobo/epdc-v5.13from
jetomit:kobo/epdc-v5.13

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@jetomit
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@jetomit jetomit commented Jul 28, 2021

Hi,

after reading in direct sunlight for half an hour today, screen refreshes suddenly became very slow, with heavy ghosting. It turns out that the temperature range table is only defined for temperatures ≤ 42 (as returned by tps6518x_get_temperature); at higher temperatures, the default index is used.

This patch is from the Kobo kernel and instead uses the highest defined index for higher temperatures (and the lowest index for lower temperatures, but that is also the default, so the behavior is the same as before). I copied the code verbatim to make the file easier to diff with the downstream kernel.

Thanks!

@akemnade
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andi@aktux:~/kobo/kernel$ git fetch https://github.com/jetomit/linux kobo/epdc-v5.13
remote: Enumerating objects: 7, done.
remote: Counting objects: 100% (3/3), done.
remote: Total 7 (delta 3), reused 3 (delta 3), pack-reused 4
Unpacking objects: 100% (7/7), 55.95 KiB | 868.00 KiB/s, done.
From https://github.com/jetomit/linux

  • branch kobo/epdc-v5.13 -> FETCH_HEAD
    andi@aktux:/kobo/kernel$ git format-patch FETCH_HEAD...FETCH_HEAD^
    0001-epdc-v2-improve-behavior-at-high-temperatures.patch
    andi@aktux:
    /kobo/kernel$ scripts/checkpatch.pl 0001-epdc-v2-improve-behavior-at-high-temperatures.patch
    ERROR: Missing Signed-off-by: line(s)

total: 1 errors, 0 warnings, 16 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.

0001-epdc-v2-improve-behavior-at-high-temperatures.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

As I am generally going to clean up things I would prefer not to include anything disliked by checkpatch.pl. So please resubmit.

When the temperature is outside the ranges defined in the temperature
range table, use the closest index (either lowest or highest).

Signed-off-by: Timotej Lazar <timotej.lazar@araneo.si>
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jetomit commented Aug 23, 2021

Fixed, thanks!

@akemnade akemnade merged commit fb1dbd5 into akemnade:kobo/epdc-v5.13 Aug 23, 2021
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and now I want to have a patch for the weather to have acutally fun with this patch ;-)

akemnade pushed a commit that referenced this pull request May 20, 2022
Some time ago 8965779 ("ipv6,mcast: always hold idev->lock before mca_lock")
switched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe
version. That was OK, because idev->lock was held for these codepaths.

In 88e2ca3 ("mld: convert ifmcaddr6 to RCU") these external locks were
removed, so we probably need to restore the original rcu-safe call.

Otherwise, we occasionally get a machine crashed/stalled with the following
in dmesg:

[ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI
[ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G           O      5.15.19-cloudflare-2022.2.1 #1
[ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV
[ 3406.009552][T230589] Workqueue: mld mld_ifc_work
[ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60
[ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b
[ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202
[ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040
[ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008
[ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000
[ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100
[ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000
[ 3406.125730][T230589] FS:  0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000
[ 3406.138992][T230589] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0
[ 3406.162421][T230589] Call Trace:
[ 3406.170235][T230589]  <TASK>
[ 3406.177736][T230589]  mld_newpack+0xfe/0x1a0
[ 3406.186686][T230589]  add_grhead+0x87/0xa0
[ 3406.195498][T230589]  add_grec+0x485/0x4e0
[ 3406.204310][T230589]  ? newidle_balance+0x126/0x3f0
[ 3406.214024][T230589]  mld_ifc_work+0x15d/0x450
[ 3406.223279][T230589]  process_one_work+0x1e6/0x380
[ 3406.232982][T230589]  worker_thread+0x50/0x3a0
[ 3406.242371][T230589]  ? rescuer_thread+0x360/0x360
[ 3406.252175][T230589]  kthread+0x127/0x150
[ 3406.261197][T230589]  ? set_kthread_struct+0x40/0x40
[ 3406.271287][T230589]  ret_from_fork+0x22/0x30
[ 3406.280812][T230589]  </TASK>
[ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders]
[ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---

Fixes: 88e2ca3 ("mld: convert ifmcaddr6 to RCU")
Reported-by: David Pinilla Caparros <dpini@cloudflare.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request May 20, 2022
alg_memory_allocated does not seem to be really used.

alg_proto does have a .memory_allocated field, but no
corresponding .sysctl_mem.

This means sk_has_account() returns true, but all sk_prot_mem_limits()
users will trigger a NULL dereference [1].

THis was not a problem until SO_RESERVE_MEM addition.

general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 3591 Comm: syz-executor153 Not tainted 5.17.0-rc3-syzkaller-00316-gb81b1829e7e3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:sk_prot_mem_limits include/net/sock.h:1523 [inline]
RIP: 0010:sock_reserve_memory+0x1d7/0x330 net/core/sock.c:1000
Code: 08 00 74 08 48 89 ef e8 27 20 bb f9 4c 03 7c 24 10 48 8b 6d 00 48 83 c5 08 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 ef e8 fb 1f bb f9 48 8b 6d 00 4c 89 ff 48
RSP: 0018:ffffc90001f1fb68 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88814aabc000 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff90e18120
RBP: 0000000000000008 R08: dffffc0000000000 R09: fffffbfff21c3025
R10: fffffbfff21c3025 R11: 0000000000000000 R12: ffffffff8d109840
R13: 0000000000001002 R14: 0000000000000001 R15: 0000000000000001
FS:  0000555556e08300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc74416f130 CR3: 0000000073d9e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 sock_setsockopt+0x14a9/0x3a30 net/core/sock.c:1446
 __sys_setsockopt+0x5af/0x980 net/socket.c:2176
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2188
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc7440fddc9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe98f07968 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc7440fddc9
RDX: 0000000000000049 RSI: 0000000000000001 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000004 R09: 00007ffe98f07990
R10: 0000000020000000 R11: 0000000000000246 R12: 00007ffe98f0798c
R13: 00007ffe98f079a0 R14: 00007ffe98f079e0 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:sk_prot_mem_limits include/net/sock.h:1523 [inline]
RIP: 0010:sock_reserve_memory+0x1d7/0x330 net/core/sock.c:1000
Code: 08 00 74 08 48 89 ef e8 27 20 bb f9 4c 03 7c 24 10 48 8b 6d 00 48 83 c5 08 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 ef e8 fb 1f bb f9 48 8b 6d 00 4c 89 ff 48
RSP: 0018:ffffc90001f1fb68 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88814aabc000 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff90e18120
RBP: 0000000000000008 R08: dffffc0000000000 R09: fffffbfff21c3025
R10: fffffbfff21c3025 R11: 0000000000000000 R12: ffffffff8d109840
R13: 0000000000001002 R14: 0000000000000001 R15: 0000000000000001
FS:  0000555556e08300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc74416f130 CR3: 0000000073d9e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000

Fixes: 2bb2f5f ("net: add new socket option SO_RESERVE_MEM")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request May 20, 2022
Compressed length can be corrupted to be a lot larger than memory
we have allocated for buffer.
This will cause memcpy in copy_compressed_segment to write outside
of allocated memory.

This mostly results in stuck read syscall but sometimes when using
btrfs send can get #GP

  kernel: general protection fault, probably for non-canonical address 0x841551d5c1000: 0000 [#1] PREEMPT SMP NOPTI
  kernel: CPU: 17 PID: 264 Comm: kworker/u256:7 Tainted: P           OE     5.17.0-rc2-1 #12
  kernel: Workqueue: btrfs-endio btrfs_work_helper [btrfs]
  kernel: RIP: 0010:lzo_decompress_bio (./include/linux/fortify-string.h:225 fs/btrfs/lzo.c:322 fs/btrfs/lzo.c:394) btrfs
  Code starting with the faulting instruction
  ===========================================
     0:*  48 8b 06                mov    (%rsi),%rax              <-- trapping instruction
     3:   48 8d 79 08             lea    0x8(%rcx),%rdi
     7:   48 83 e7 f8             and    $0xfffffffffffffff8,%rdi
     b:   48 89 01                mov    %rax,(%rcx)
     e:   44 89 f0                mov    %r14d,%eax
    11:   48 8b 54 06 f8          mov    -0x8(%rsi,%rax,1),%rdx
  kernel: RSP: 0018:ffffb110812efd50 EFLAGS: 00010212
  kernel: RAX: 0000000000001000 RBX: 000000009ca264c8 RCX: ffff98996e6d8ff8
  kernel: RDX: 0000000000000064 RSI: 000841551d5c1000 RDI: ffffffff9500435d
  kernel: RBP: ffff989a3be856c0 R08: 0000000000000000 R09: 0000000000000000
  kernel: R10: 0000000000000000 R11: 0000000000001000 R12: ffff98996e6d8000
  kernel: R13: 0000000000000008 R14: 0000000000001000 R15: 000841551d5c1000
  kernel: FS:  0000000000000000(0000) GS:ffff98a09d640000(0000) knlGS:0000000000000000
  kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  kernel: CR2: 00001e9f984d9ea8 CR3: 000000014971a000 CR4: 00000000003506e0
  kernel: Call Trace:
  kernel:  <TASK>
  kernel: end_compressed_bio_read (fs/btrfs/compression.c:104 fs/btrfs/compression.c:1363 fs/btrfs/compression.c:323) btrfs
  kernel: end_workqueue_fn (fs/btrfs/disk-io.c:1923) btrfs
  kernel: btrfs_work_helper (fs/btrfs/async-thread.c:326) btrfs
  kernel: process_one_work (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:212 ./include/trace/events/workqueue.h:108 kernel/workqueue.c:2312)
  kernel: worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2455)
  kernel: ? process_one_work (kernel/workqueue.c:2397)
  kernel: kthread (kernel/kthread.c:377)
  kernel: ? kthread_complete_and_exit (kernel/kthread.c:332)
  kernel: ret_from_fork (arch/x86/entry/entry_64.S:301)
  kernel:  </TASK>

CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Dāvis Mosāns <davispuh@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request May 20, 2022
Booting a MACCHIATObin with 5.17, the system OOPs with
a null pointer deref when the network is started. This
is caused by the pcs->ops structure being null in
mcpp2_acpi_start() when it tries to call pcs_config().

Hoisting the code which sets pcs_gmac.ops and pcs_xlg.ops,
assuring they are always set, fixes the problem.

The OOPs looks like:
[   18.687760] Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000010
[   18.698561] Mem abort info:
[   18.698564]   ESR = 0x96000004
[   18.698567]   EC = 0x25: DABT (current EL), IL = 32 bits
[   18.709821]   SET = 0, FnV = 0
[   18.714292]   EA = 0, S1PTW = 0
[   18.718833]   FSC = 0x04: level 0 translation fault
[   18.725126] Data abort info:
[   18.729408]   ISV = 0, ISS = 0x00000004
[   18.734655]   CM = 0, WnR = 0
[   18.738933] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000111bbf000
[   18.745409] [0000000000000010] pgd=0000000000000000, p4d=0000000000000000
[   18.752235] Internal error: Oops: 96000004 [#1] SMP
[   18.757134] Modules linked in: rfkill ip_set nf_tables nfnetlink qrtr sunrpc vfat fat omap_rng fuse zram xfs crct10dif_ce mvpp2 ghash_ce sbsa_gwdt phylink xhci_plat_hcd ahci_plam
[   18.773481] CPU: 0 PID: 681 Comm: NetworkManager Not tainted 5.17.0-0.rc3.89.fc36.aarch64 #1
[   18.781954] Hardware name: Marvell                         Armada 7k/8k Family Board      /Armada 7k/8k Family Board      , BIOS EDK II Jun  4 2019
[   18.795222] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   18.802213] pc : mvpp2_start_dev+0x2b0/0x300 [mvpp2]
[   18.807208] lr : mvpp2_start_dev+0x298/0x300 [mvpp2]
[   18.812197] sp : ffff80000b4732c0
[   18.815522] x29: ffff80000b4732c0 x28: 0000000000000000 x27: ffffccab38ae57f8
[   18.822689] x26: ffff6eeb03065a10 x25: ffff80000b473a30 x24: ffff80000b4735b8
[   18.829855] x23: 0000000000000000 x22: 00000000000001e0 x21: ffff6eeb07b6ab68
[   18.837021] x20: ffff6eeb07b6ab30 x19: ffff6eeb07b6a9c0 x18: 0000000000000014
[   18.844187] x17: 00000000f6232bfe x16: ffffccab899b1dc0 x15: 000000006a30f9fa
[   18.851353] x14: 000000003b77bd50 x13: 000006dc896f0e8e x12: 001bbbfccfd0d3a2
[   18.858519] x11: 0000000000001528 x10: 0000000000001548 x9 : ffffccab38ad0fb0
[   18.865685] x8 : ffff80000b473330 x7 : 0000000000000000 x6 : 0000000000000000
[   18.872851] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80000b4732f8
[   18.880017] x2 : 000000000000001a x1 : 0000000000000002 x0 : ffff6eeb07b6ab68
[   18.887183] Call trace:
[   18.889637]  mvpp2_start_dev+0x2b0/0x300 [mvpp2]
[   18.894279]  mvpp2_open+0x134/0x2b4 [mvpp2]
[   18.898483]  __dev_open+0x128/0x1e4
[   18.901988]  __dev_change_flags+0x17c/0x1d0
[   18.906187]  dev_change_flags+0x30/0x70
[   18.910038]  do_setlink+0x278/0xa7c
[   18.913540]  __rtnl_newlink+0x44c/0x7d0
[   18.917391]  rtnl_newlink+0x5c/0x8c
[   18.920892]  rtnetlink_rcv_msg+0x254/0x314
[   18.925006]  netlink_rcv_skb+0x48/0x10c
[   18.928858]  rtnetlink_rcv+0x24/0x30
[   18.932449]  netlink_unicast+0x290/0x2f4
[   18.936386]  netlink_sendmsg+0x1d0/0x41c
[   18.940323]  sock_sendmsg+0x60/0x70
[   18.943825]  ____sys_sendmsg+0x248/0x260
[   18.947762]  ___sys_sendmsg+0x74/0xa0
[   18.951438]  __sys_sendmsg+0x64/0xcc
[   18.955027]  __arm64_sys_sendmsg+0x30/0x40
[   18.959140]  invoke_syscall+0x50/0x120
[   18.962906]  el0_svc_common.constprop.0+0x4c/0xf4
[   18.967629]  do_el0_svc+0x30/0x9c
[   18.970958]  el0_svc+0x28/0xb0
[   18.974025]  el0t_64_sync_handler+0x10c/0x140
[   18.978400]  el0t_64_sync+0x1a4/0x1a8
[   18.982078] Code: 52800004 b9416262 aa1503e0 52800041 (f94008a5)
[   18.988196] ---[ end trace 0000000000000000 ]---

Fixes: cff0563 ("net: mvpp2: use .mac_select_pcs() interface")
Suggested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Marcin Wojtas <mw@semihalf.com>
Link: https://lore.kernel.org/r/20220214231852.3331430-1-jeremy.linton@arm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
If an attempt is made to a sensor with a thermal zone and it fails,
the call to devm_thermal_zone_of_sensor_register() may return -ENODEV.
This may result in crashes similar to the following.

Unable to handle kernel NULL pointer dereference at virtual address 00000000000003cd
...
Internal error: Oops: 96000021 [#1] PREEMPT SMP
...
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : mutex_lock+0x18/0x60
lr : thermal_zone_device_update+0x40/0x2e0
sp : ffff800014c4fc60
x29: ffff800014c4fc60 x28: ffff365ee3f6e000 x27: ffffdde218426790
x26: ffff365ee3f6e000 x25: 0000000000000000 x24: ffff365ee3f6e000
x23: ffffdde218426870 x22: ffff365ee3f6e000 x21: 00000000000003cd
x20: ffff365ee8bf3308 x19: ffffffffffffffed x18: 0000000000000000
x17: ffffdde21842689c x16: ffffdde1cb7a0b7c x15: 0000000000000040
x14: ffffdde21a4889a0 x13: 0000000000000228 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000001120000 x7 : 0000000000000001 x6 : 0000000000000000
x5 : 0068000878e20f07 x4 : 0000000000000000 x3 : 00000000000003cd
x2 : ffff365ee3f6e000 x1 : 0000000000000000 x0 : 00000000000003cd
Call trace:
 mutex_lock+0x18/0x60
 hwmon_notify_event+0xfc/0x110
 0xffffdde1cb7a0a90
 0xffffdde1cb7a0b7c
 irq_thread_fn+0x2c/0xa0
 irq_thread+0x134/0x240
 kthread+0x178/0x190
 ret_from_fork+0x10/0x20
Code: d503201f d503201f d2800001 aa0103e4 (c8e47c02)

Jon Hunter reports that the exact call sequence is:

hwmon_notify_event()
  --> hwmon_thermal_notify()
    --> thermal_zone_device_update()
      --> update_temperature()
        --> mutex_lock()

The hwmon core needs to handle all errors returned from calls
to devm_thermal_zone_of_sensor_register(). If the call fails
with -ENODEV, report that the sensor was not attached to a
thermal zone  but continue to register the hwmon device.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Cc: Dmitry Osipenko <digetx@gmail.com>
Fixes: 1597b37 ("hwmon: Add notification support")
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
akemnade pushed a commit that referenced this pull request May 20, 2022
If a bridged port is not offloaded to the hardware - either because the
underlying driver does not implement the port_bridge_{join,leave} ops,
or because the operation failed - then its dp->bridge pointer will be
NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL.

This fixes the following splat when removing a port from a bridge:

 Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000
 Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP
 CPU: 3 PID: 1119 Comm: brctl Tainted: G           O      5.17.0-rc4-rt4 #1
 Call trace:
  dsa_port_bridge_leave+0x8c/0x1e4
  dsa_slave_changeupper+0x40/0x170
  dsa_slave_netdevice_event+0x494/0x4d4
  notifier_call_chain+0x80/0xe0
  raw_notifier_call_chain+0x1c/0x24
  call_netdevice_notifiers_info+0x5c/0xac
  __netdev_upper_dev_unlink+0xa4/0x200
  netdev_upper_dev_unlink+0x38/0x60
  del_nbp+0x1b0/0x300
  br_del_if+0x38/0x114
  add_del_if+0x60/0xa0
  br_ioctl_stub+0x128/0x2dc
  br_ioctl_call+0x68/0xb0
  dev_ifsioc+0x390/0x554
  dev_ioctl+0x128/0x400
  sock_do_ioctl+0xb4/0xf4
  sock_ioctl+0x12c/0x4e0
  __arm64_sys_ioctl+0xa8/0xf0
  invoke_syscall+0x4c/0x110
  el0_svc_common.constprop.0+0x48/0xf0
  do_el0_svc+0x28/0x84
  el0_svc+0x1c/0x50
  el0t_64_sync_handler+0xa8/0xb0
  el0t_64_sync+0x17c/0x180
 Code: f9402f00 f0002261 f9401302 913cc021 (a9401404)
 ---[ end trace 0000000000000000 ]---

Fixes: d3eed0e ("net: dsa: keep the bridge_dev and bridge_num as part of the same structure")
Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220221203539.310690-1-alvin@pqrs.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
The trace_hardirqs_{on,off}() require the caller to setup frame pointer
properly. This because these two functions use macro 'CALLER_ADDR1' (aka.
__builtin_return_address(1)) to acquire caller info. If the $fp is used
for other purpose, the code generated this macro (as below) could trigger
memory access fault.

   0xffffffff8011510e <+80>:    ld      a1,-16(s0)
   0xffffffff80115112 <+84>:    ld      s2,-8(a1)  # <-- paging fault here

The oops message during booting if compiled with 'irqoff' tracer enabled:
[    0.039615][    T0] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000f8
[    0.041925][    T0] Oops [#1]
[    0.042063][    T0] Modules linked in:
[    0.042864][    T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.17.0-rc1-00233-g9a20c48d1ed2 #29
[    0.043568][    T0] Hardware name: riscv-virtio,qemu (DT)
[    0.044343][    T0] epc : trace_hardirqs_on+0x56/0xe2
[    0.044601][    T0]  ra : restore_all+0x12/0x6e
[    0.044721][    T0] epc : ffffffff80126a5c ra : ffffffff80003b94 sp : ffffffff81403db0
[    0.044801][    T0]  gp : ffffffff8163acd8 tp : ffffffff81414880 t0 : 0000000000000020
[    0.044882][    T0]  t1 : 0098968000000000 t2 : 0000000000000000 s0 : ffffffff81403de0
[    0.044967][    T0]  s1 : 0000000000000000 a0 : 0000000000000001 a1 : 0000000000000100
[    0.045046][    T0]  a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000
[    0.045124][    T0]  a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000054494d45
[    0.045210][    T0]  s2 : ffffffff80003b94 s3 : ffffffff81a8f1b0 s4 : ffffffff80e27b50
[    0.045289][    T0]  s5 : ffffffff81414880 s6 : ffffffff8160fa00 s7 : 00000000800120e8
[    0.045389][    T0]  s8 : 0000000080013100 s9 : 000000000000007f s10: 0000000000000000
[    0.045474][    T0]  s11: 0000000000000000 t3 : 7fffffffffffffff t4 : 0000000000000000
[    0.045548][    T0]  t5 : 0000000000000000 t6 : ffffffff814aa368
[    0.045620][    T0] status: 0000000200000100 badaddr: 00000000000000f8 cause: 000000000000000d
[    0.046402][    T0] [<ffffffff80003b94>] restore_all+0x12/0x6e

This because the $fp(aka. $s0) register is not used as frame pointer in the
assembly entry code.

	resume_kernel:
		REG_L s0, TASK_TI_PREEMPT_COUNT(tp)
		bnez s0, restore_all
		REG_L s0, TASK_TI_FLAGS(tp)
                andi s0, s0, _TIF_NEED_RESCHED
                beqz s0, restore_all
                call preempt_schedule_irq
                j restore_all

To fix above issue, here we add one extra level wrapper for function
trace_hardirqs_{on,off}() so they can be safely called by low level entry
code.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Fixes: 3c46979 ("riscv: Enable LOCKDEP_SUPPORT & fixup TRACE_IRQFLAGS_SUPPORT")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
akemnade pushed a commit that referenced this pull request May 20, 2022
…arge

Syzkaller with UBSAN uncovered a scenario where a large number of
DATA_FIN retransmits caused a shift-out-of-bounds in the DATA_FIN
timeout calculation:

================================================================================
UBSAN: shift-out-of-bounds in net/mptcp/protocol.c:470:29
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 1 PID: 13059 Comm: kworker/1:0 Not tainted 5.17.0-rc2-00630-g5fbf21c90c60 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Workqueue: events mptcp_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds.cold+0xb2/0x20e lib/ubsan.c:330
 mptcp_set_datafin_timeout net/mptcp/protocol.c:470 [inline]
 __mptcp_retrans.cold+0x72/0x77 net/mptcp/protocol.c:2445
 mptcp_worker+0x58a/0xa70 net/mptcp/protocol.c:2528
 process_one_work+0x9df/0x16d0 kernel/workqueue.c:2307
 worker_thread+0x95/0xe10 kernel/workqueue.c:2454
 kthread+0x2f4/0x3b0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
================================================================================

This change limits the maximum timeout by limiting the size of the
shift, which keeps all intermediate values in-bounds.

Closes: multipath-tcp/mptcp_net-next#259
Fixes: 6477dd3 ("mptcp: Retransmit DATA_FIN")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
xennet_destroy_queues() relies on info->netdev->real_num_tx_queues to
delete queues. Since d7dac08
("net-sysfs: update the queue counts in the unregistration path"),
unregister_netdev() indirectly sets real_num_tx_queues to 0. Those two
facts together means, that xennet_destroy_queues() called from
xennet_remove() cannot do its job, because it's called after
unregister_netdev(). This results in kfree-ing queues that are still
linked in napi, which ultimately crashes:

    BUG: kernel NULL pointer dereference, address: 0000000000000000
    #PF: supervisor read access in kernel mode
    #PF: error_code(0x0000) - not-present page
    PGD 0 P4D 0
    Oops: 0000 [#1] PREEMPT SMP PTI
    CPU: 1 PID: 52 Comm: xenwatch Tainted: G        W         5.16.10-1.32.fc32.qubes.x86_64+ #226
    RIP: 0010:free_netdev+0xa3/0x1a0
    Code: ff 48 89 df e8 2e e9 00 00 48 8b 43 50 48 8b 08 48 8d b8 a0 fe ff ff 48 8d a9 a0 fe ff ff 49 39 c4 75 26 eb 47 e8 ed c1 66 ff <48> 8b 85 60 01 00 00 48 8d 95 60 01 00 00 48 89 ef 48 2d 60 01 00
    RSP: 0000:ffffc90000bcfd00 EFLAGS: 00010286
    RAX: 0000000000000000 RBX: ffff88800edad000 RCX: 0000000000000000
    RDX: 0000000000000001 RSI: ffffc90000bcfc30 RDI: 00000000ffffffff
    RBP: fffffffffffffea0 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800edad050
    R13: ffff8880065f8f88 R14: 0000000000000000 R15: ffff8880066c6680
    FS:  0000000000000000(0000) GS:ffff8880f3300000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000000 CR3: 00000000e998c006 CR4: 00000000003706e0
    Call Trace:
     <TASK>
     xennet_remove+0x13d/0x300 [xen_netfront]
     xenbus_dev_remove+0x6d/0xf0
     __device_release_driver+0x17a/0x240
     device_release_driver+0x24/0x30
     bus_remove_device+0xd8/0x140
     device_del+0x18b/0x410
     ? _raw_spin_unlock+0x16/0x30
     ? klist_iter_exit+0x14/0x20
     ? xenbus_dev_request_and_reply+0x80/0x80
     device_unregister+0x13/0x60
     xenbus_dev_changed+0x18e/0x1f0
     xenwatch_thread+0xc0/0x1a0
     ? do_wait_intr_irq+0xa0/0xa0
     kthread+0x16b/0x190
     ? set_kthread_struct+0x40/0x40
     ret_from_fork+0x22/0x30
     </TASK>

Fix this by calling xennet_destroy_queues() from xennet_uninit(),
when real_num_tx_queues is still available. This ensures that queues are
destroyed when real_num_tx_queues is set to 0, regardless of how
unregister_netdev() was called.

Originally reported at
QubesOS/qubes-issues#7257

Fixes: d7dac08 ("net-sysfs: update the queue counts in the unregistration path")
Cc: stable@vger.kernel.org
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request May 20, 2022
When enabling VMD and IOMMU scalable mode, the following kernel panic
call trace/kernel log is shown in Eagle Stream platform (Sapphire Rapids
CPU) during booting:

pci 0000:59:00.5: Adding to iommu group 42
...
vmd 0000:59:00.5: PCI host bridge to bus 10000:80
pci 10000:80:01.0: [8086:352a] type 01 class 0x060400
pci 10000:80:01.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:01.0: enabling Extended Tags
pci 10000:80:01.0: PME# supported from D0 D3hot D3cold
pci 10000:80:01.0: DMAR: Setup RID2PASID failed
pci 10000:80:01.0: Failed to add to iommu group 42: -16
pci 10000:80:03.0: [8086:352b] type 01 class 0x060400
pci 10000:80:03.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:03.0: enabling Extended Tags
pci 10000:80:03.0: PME# supported from D0 D3hot D3cold
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:29!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-rc3+ #7
Hardware name: Lenovo ThinkSystem SR650V3/SB27A86647, BIOS ESE101Y-1.00 01/13/2022
Workqueue: events work_for_cpu_fn
RIP: 0010:__list_add_valid.cold+0x26/0x3f
Code: 9a 4a ab ff 4c 89 c1 48 c7 c7 40 0c d9 9e e8 b9 b1 fe ff 0f
      0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 f0 0c d9 9e e8 a2 b1
      fe ff <0f> 0b 48 89 d1 4c 89 c6 4c 89 ca 48 c7 c7 98 0c d9
      9e e8 8b b1 fe
RSP: 0000:ff5ad434865b3a40 EFLAGS: 00010246
RAX: 0000000000000058 RBX: ff4d61160b74b880 RCX: ff4d61255e1fffa8
RDX: 0000000000000000 RSI: 00000000fffeffff RDI: ffffffff9fd34f20
RBP: ff4d611d8e245c00 R08: 0000000000000000 R09: ff5ad434865b3888
R10: ff5ad434865b3880 R11: ff4d61257fdc6fe8 R12: ff4d61160b74b8a0
R13: ff4d61160b74b8a0 R14: ff4d611d8e245c10 R15: ff4d611d8001ba70
FS:  0000000000000000(0000) GS:ff4d611d5ea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ff4d611fa1401000 CR3: 0000000aa0210001 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 intel_pasid_alloc_table+0x9c/0x1d0
 dmar_insert_one_dev_info+0x423/0x540
 ? device_to_iommu+0x12d/0x2f0
 intel_iommu_attach_device+0x116/0x290
 __iommu_attach_device+0x1a/0x90
 iommu_group_add_device+0x190/0x2c0
 __iommu_probe_device+0x13e/0x250
 iommu_probe_device+0x24/0x150
 iommu_bus_notifier+0x69/0x90
 blocking_notifier_call_chain+0x5a/0x80
 device_add+0x3db/0x7b0
 ? arch_memremap_can_ram_remap+0x19/0x50
 ? memremap+0x75/0x140
 pci_device_add+0x193/0x1d0
 pci_scan_single_device+0xb9/0xf0
 pci_scan_slot+0x4c/0x110
 pci_scan_child_bus_extend+0x3a/0x290
 vmd_enable_domain.constprop.0+0x63e/0x820
 vmd_probe+0x163/0x190
 local_pci_probe+0x42/0x80
 work_for_cpu_fn+0x13/0x20
 process_one_work+0x1e2/0x3b0
 worker_thread+0x1c4/0x3a0
 ? rescuer_thread+0x370/0x370
 kthread+0xc7/0xf0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x1f/0x30
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
...
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x1ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]---

The following 'lspci' output shows devices '10000:80:*' are subdevices of
the VMD device 0000:59:00.5:

  $ lspci
  ...
  0000:59:00.5 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller (rev 20)
  ...
  10000:80:01.0 PCI bridge: Intel Corporation Device 352a (rev 03)
  10000:80:03.0 PCI bridge: Intel Corporation Device 352b (rev 03)
  10000:80:05.0 PCI bridge: Intel Corporation Device 352c (rev 03)
  10000:80:07.0 PCI bridge: Intel Corporation Device 352d (rev 03)
  10000:81:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]
  10000:82:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]

The symptom 'list_add double add' is caused by the following failure
message:

  pci 10000:80:01.0: DMAR: Setup RID2PASID failed
  pci 10000:80:01.0: Failed to add to iommu group 42: -16
  pci 10000:80:03.0: [8086:352b] type 01 class 0x060400

Device 10000:80:01.0 is the subdevice of the VMD device 0000:59:00.5,
so invoking intel_pasid_alloc_table() gets the pasid_table of the VMD
device 0000:59:00.5. Here is call path:

  intel_pasid_alloc_table
    pci_for_each_dma_alias
     get_alias_pasid_table
       search_pasid_table

pci_real_dma_dev() in pci_for_each_dma_alias() gets the real dma device
which is the VMD device 0000:59:00.5. However, pte of the VMD device
0000:59:00.5 has been configured during this message "pci 0000:59:00.5:
Adding to iommu group 42". So, the status -EBUSY is returned when
configuring pasid entry for device 10000:80:01.0.

It then invokes dmar_remove_one_dev_info() to release
'struct device_domain_info *' from iommu_devinfo_cache. But, the pasid
table is not released because of the following statement in
__dmar_remove_one_dev_info():

	if (info->dev && !dev_is_real_dma_subdevice(info->dev)) {
		...
		intel_pasid_free_table(info->dev);
        }

The subsequent dmar_insert_one_dev_info() operation of device
10000:80:03.0 allocates 'struct device_domain_info *' from
iommu_devinfo_cache. The allocated address is the same address that
is released previously for device 10000:80:01.0. Finally, invoking
device_attach_pasid_table() causes the issue.

`git bisect` points to the offending commit 474dd1c ("iommu/vt-d:
Fix clearing real DMA device's scalable-mode context entries"), which
releases the pasid table if the device is not the subdevice by
checking the returned status of dev_is_real_dma_subdevice().
Reverting the offending commit can work around the issue.

The solution is to prevent from allocating pasid table if those
devices are subdevices of the VMD device.

Fixes: 474dd1c ("iommu/vt-d: Fix clearing real DMA device's scalable-mode context entries")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Link: https://lore.kernel.org/r/20220216091307.703-1-adrianhuang0701@gmail.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220221053348.262724-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
akemnade pushed a commit that referenced this pull request May 20, 2022
This driver, like several others, uses a chained IRQ for each GPIO bank,
and forwards .irq_set_wake to the GPIO bank's upstream IRQ. As a result,
a call to irq_set_irq_wake() needs to lock both the upstream and
downstream irq_desc's. Lockdep considers this to be a possible deadlock
when the irq_desc's share lockdep classes, which they do by default:

 ============================================
 WARNING: possible recursive locking detected
 5.17.0-rc3-00394-gc849047c2473 #1 Not tainted
 --------------------------------------------
 init/307 is trying to acquire lock:
 c2dfe27c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0x58/0xa0

 but task is already holding lock:
 c3c0ac7 (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0x58/0xa0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&irq_desc_lock_class);
   lock(&irq_desc_lock_class);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by init/307:
  #0: c1f29f18 (system_transition_mutex){+.+.}-{3:3}, at: __do_sys_reboot+0x90/0x23c
  #1: c20f7760 (&dev->mutex){....}-{3:3}, at: device_shutdown+0xf4/0x224
  #2: c2e804d8 (&dev->mutex){....}-{3:3}, at: device_shutdown+0x104/0x224
  #3: c3c0ac7 (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0x58/0xa0

 stack backtrace:
 CPU: 0 PID: 307 Comm: init Not tainted 5.17.0-rc3-00394-gc849047c2473 #1
 Hardware name: Allwinner sun8i Family
  unwind_backtrace from show_stack+0x10/0x14
  show_stack from dump_stack_lvl+0x68/0x90
  dump_stack_lvl from __lock_acquire+0x1680/0x31a0
  __lock_acquire from lock_acquire+0x148/0x3dc
  lock_acquire from _raw_spin_lock_irqsave+0x50/0x6c
  _raw_spin_lock_irqsave from __irq_get_desc_lock+0x58/0xa0
  __irq_get_desc_lock from irq_set_irq_wake+0x2c/0x19c
  irq_set_irq_wake from irq_set_irq_wake+0x13c/0x19c
    [tail call from sunxi_pinctrl_irq_set_wake]
  irq_set_irq_wake from gpio_keys_suspend+0x80/0x1a4
  gpio_keys_suspend from gpio_keys_shutdown+0x10/0x2c
  gpio_keys_shutdown from device_shutdown+0x180/0x224
  device_shutdown from __do_sys_reboot+0x134/0x23c
  __do_sys_reboot from ret_fast_syscall+0x0/0x1c

However, this can never deadlock because the upstream and downstream
IRQs are never the same (nor do they even involve the same irqchip).

Silence this erroneous lockdep splat by applying what appears to be the
usual fix of moving the GPIO IRQs to separate lockdep classes.

Fixes: a59c99d ("pinctrl: sunxi: Forward calls to irq_set_irq_wake")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220216040037.22730-1-samuel@sholland.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
When "debugfs=off" is used on the kernel command line, iwiwifi's
mvm module uses an invalid/unchecked debugfs_dir pointer and causes
a BUG:

 BUG: kernel NULL pointer dereference, address: 000000000000004f
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] PREEMPT SMP
 CPU: 1 PID: 503 Comm: modprobe Tainted: G        W         5.17.0-rc5 #7
 Hardware name: Dell Inc. Inspiron 15 5510/076F7Y, BIOS 2.4.1 11/05/2021
 RIP: 0010:iwl_mvm_dbgfs_register+0x692/0x700 [iwlmvm]
 Code: 69 a0 be 80 01 00 00 48 c7 c7 50 73 6a a0 e8 95 cf ee e0 48 8b 83 b0 1e 00 00 48 c7 c2 54 73 6a a0 be 64 00 00 00 48 8d 7d 8c <48> 8b 48 50 e8 15 22 07 e1 48 8b 43 28 48 8d 55 8c 48 c7 c7 5f 73
 RSP: 0018:ffffc90000a0ba68 EFLAGS: 00010246
 RAX: ffffffffffffffff RBX: ffff88817d6e3328 RCX: ffff88817d6e3328
 RDX: ffffffffa06a7354 RSI: 0000000000000064 RDI: ffffc90000a0ba6c
 RBP: ffffc90000a0bae0 R08: ffffffff824e4880 R09: ffffffffa069d620
 R10: ffffc90000a0ba00 R11: ffffffffffffffff R12: 0000000000000000
 R13: ffffc90000a0bb28 R14: ffff88817d6e3328 R15: ffff88817d6e3320
 FS:  00007f64dd92d740(0000) GS:ffff88847f640000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000000000000004f CR3: 000000016fc79001 CR4: 0000000000770ee0
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? iwl_mvm_mac_setup_register+0xbdc/0xda0 [iwlmvm]
  iwl_mvm_start_post_nvm+0x71/0x100 [iwlmvm]
  iwl_op_mode_mvm_start+0xab8/0xb30 [iwlmvm]
  _iwl_op_mode_start+0x6f/0xd0 [iwlwifi]
  iwl_opmode_register+0x6a/0xe0 [iwlwifi]
  ? 0xffffffffa0231000
  iwl_mvm_init+0x35/0x1000 [iwlmvm]
  ? 0xffffffffa0231000
  do_one_initcall+0x5a/0x1b0
  ? kmem_cache_alloc+0x1e5/0x2f0
  ? do_init_module+0x1e/0x220
  do_init_module+0x48/0x220
  load_module+0x2602/0x2bc0
  ? __kernel_read+0x145/0x2e0
  ? kernel_read_file+0x229/0x290
  __do_sys_finit_module+0xc5/0x130
  ? __do_sys_finit_module+0xc5/0x130
  __x64_sys_finit_module+0x13/0x20
  do_syscall_64+0x38/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f64dda564dd
 Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1b 29 0f 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffdba393f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64dda564dd
 RDX: 0000000000000000 RSI: 00005575399e2ab2 RDI: 0000000000000001
 RBP: 000055753a91c5e0 R08: 0000000000000000 R09: 0000000000000002
 R10: 0000000000000001 R11: 0000000000000246 R12: 00005575399e2ab2
 R13: 000055753a91ceb0 R14: 0000000000000000 R15: 000055753a923018
  </TASK>
 Modules linked in: btintel(+) btmtk bluetooth vfat snd_hda_codec_hdmi fat snd_hda_codec_realtek snd_hda_codec_generic iwlmvm(+) snd_sof_pci_intel_tgl mac80211 snd_sof_intel_hda_common soundwire_intel soundwire_generic_allocation soundwire_cadence soundwire_bus snd_sof_intel_hda snd_sof_pci snd_sof snd_sof_xtensa_dsp snd_soc_hdac_hda snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core btrfs snd_compress snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec raid6_pq iwlwifi snd_hda_core snd_pcm snd_timer snd soundcore cfg80211 intel_ish_ipc(+) thunderbolt rfkill intel_ishtp ucsi_acpi wmi i2c_hid_acpi i2c_hid evdev
 CR2: 000000000000004f
 ---[ end trace 0000000000000000 ]---

Check the debugfs_dir pointer for an error before using it.

Fixes: 8c082a9 ("iwlwifi: mvm: simplify iwl_mvm_dbgfs_register")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Luca Coelho <luciano.coelho@intel.com>
Cc: linux-wireless@vger.kernel.org
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220223030630.23241-1-rdunlap@infradead.org
[change to make both conditional]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
akemnade pushed a commit that referenced this pull request May 20, 2022
Commit 54659ca ("staging: rtl8723bs: remove possible deadlock when
disconnect (v2)") split the locking of pxmitpriv->lock vs sleep_q/lock
into 2 locks in attempt to fix a lockdep reported issue with the locking
order of the sta_hash_lock vs pxmitpriv->lock.

But in the end this turned out to not fully solve the sta_hash_lock issue
so commit a7ac783 ("staging: rtl8723bs: remove a second possible
deadlock") was added to fix this in another way.

The original fix was kept as it was still seen as a good thing to have,
but now it turns out that it creates a deadlock in access-point mode:

[Feb20 23:47] ======================================================
[  +0.074085] WARNING: possible circular locking dependency detected
[  +0.074077] 5.16.0-1-amd64 #1 Tainted: G         C  E
[  +0.064710] ------------------------------------------------------
[  +0.074075] ksoftirqd/3/29 is trying to acquire lock:
[  +0.060542] ffffb8b30062ab00 (&pxmitpriv->lock){+.-.}-{2:2}, at: rtw_xmit_classifier+0x8a/0x140 [r8723bs]
[  +0.114921]
              but task is already holding lock:
[  +0.069908] ffffb8b3007ab704 (&psta->sleep_q.lock){+.-.}-{2:2}, at: wakeup_sta_to_xmit+0x3b/0x300 [r8723bs]
[  +0.116976]
              which lock already depends on the new lock.

[  +0.098037]
              the existing dependency chain (in reverse order) is:
[  +0.089704]
              -> #1 (&psta->sleep_q.lock){+.-.}-{2:2}:
[  +0.077232]        _raw_spin_lock_bh+0x34/0x40
[  +0.053261]        xmitframe_enqueue_for_sleeping_sta+0xc1/0x2f0 [r8723bs]
[  +0.082572]        rtw_xmit+0x58b/0x940 [r8723bs]
[  +0.056528]        _rtw_xmit_entry+0xba/0x350 [r8723bs]
[  +0.062755]        dev_hard_start_xmit+0xf1/0x320
[  +0.056381]        sch_direct_xmit+0x9e/0x360
[  +0.052212]        __dev_queue_xmit+0xce4/0x1080
[  +0.055334]        ip6_finish_output2+0x18f/0x6e0
[  +0.056378]        ndisc_send_skb+0x2c8/0x870
[  +0.052209]        ndisc_send_ns+0xd3/0x210
[  +0.050130]        addrconf_dad_work+0x3df/0x5a0
[  +0.055338]        process_one_work+0x274/0x5a0
[  +0.054296]        worker_thread+0x52/0x3b0
[  +0.050124]        kthread+0x16c/0x1a0
[  +0.044925]        ret_from_fork+0x1f/0x30
[  +0.049092]
              -> #0 (&pxmitpriv->lock){+.-.}-{2:2}:
[  +0.074101]        __lock_acquire+0x10f5/0x1d80
[  +0.054298]        lock_acquire+0xd7/0x300
[  +0.049088]        _raw_spin_lock_bh+0x34/0x40
[  +0.053248]        rtw_xmit_classifier+0x8a/0x140 [r8723bs]
[  +0.066949]        rtw_xmitframe_enqueue+0xa/0x20 [r8723bs]
[  +0.066946]        rtl8723bs_hal_xmitframe_enqueue+0x14/0x50 [r8723bs]
[  +0.078386]        wakeup_sta_to_xmit+0xa6/0x300 [r8723bs]
[  +0.065903]        rtw_recv_entry+0xe36/0x1160 [r8723bs]
[  +0.063809]        rtl8723bs_recv_tasklet+0x349/0x6c0 [r8723bs]
[  +0.071093]        tasklet_action_common.constprop.0+0xe5/0x110
[  +0.070966]        __do_softirq+0x16f/0x50a
[  +0.050134]        __irq_exit_rcu+0xeb/0x140
[  +0.051172]        irq_exit_rcu+0xa/0x20
[  +0.047006]        common_interrupt+0xb8/0xd0
[  +0.052214]        asm_common_interrupt+0x1e/0x40
[  +0.056381]        finish_task_switch.isra.0+0x100/0x3a0
[  +0.063670]        __schedule+0x3ad/0xd20
[  +0.048047]        schedule+0x4e/0xc0
[  +0.043880]        smpboot_thread_fn+0xc4/0x220
[  +0.054298]        kthread+0x16c/0x1a0
[  +0.044922]        ret_from_fork+0x1f/0x30
[  +0.049088]
              other info that might help us debug this:

[  +0.095950]  Possible unsafe locking scenario:

[  +0.070952]        CPU0                    CPU1
[  +0.054282]        ----                    ----
[  +0.054285]   lock(&psta->sleep_q.lock);
[  +0.047004]                                lock(&pxmitpriv->lock);
[  +0.074082]                                lock(&psta->sleep_q.lock);
[  +0.077209]   lock(&pxmitpriv->lock);
[  +0.043873]
               *** DEADLOCK ***

[  +0.070950] 1 lock held by ksoftirqd/3/29:
[  +0.049082]  #0: ffffb8b3007ab704 (&psta->sleep_q.lock){+.-.}-{2:2}, at: wakeup_sta_to_xmit+0x3b/0x300 [r8723bs]

Analysis shows that in hindsight the splitting of the lock was not
a good idea, so revert this to fix the access-point mode deadlock.

Note this is a straight-forward revert done with git revert, the commented
out "/* spin_lock_bh(&psta_bmc->sleep_q.lock); */" lines were part of the
code before the reverted changes.

Fixes: 54659ca ("staging: rtl8723bs: remove possible deadlock when disconnect (v2)")
Cc: stable <stable@vger.kernel.org>
Cc: Fabio Aiuto <fabioaiuto83@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215542
Link: https://lore.kernel.org/r/20220302101637.26542-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
…_transaction()

We are seeing crashes similar to the following trace:

[38.969182] WARNING: CPU: 20 PID: 2105 at fs/btrfs/relocation.c:4070 btrfs_relocate_block_group+0x2dc/0x340 [btrfs]
[38.973556] CPU: 20 PID: 2105 Comm: btrfs Not tainted 5.17.0-rc4 #54
[38.974580] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[38.976539] RIP: 0010:btrfs_relocate_block_group+0x2dc/0x340 [btrfs]
[38.980336] RSP: 0000:ffffb0dd42e03c20 EFLAGS: 00010206
[38.981218] RAX: ffff96cfc4ede800 RBX: ffff96cfc3ce0000 RCX: 000000000002ca14
[38.982560] RDX: 0000000000000000 RSI: 4cfd109a0bcb5d7f RDI: ffff96cfc3ce0360
[38.983619] RBP: ffff96cfc309c000 R08: 0000000000000000 R09: 0000000000000000
[38.984678] R10: ffff96cec0000001 R11: ffffe84c80000000 R12: ffff96cfc4ede800
[38.985735] R13: 0000000000000000 R14: 0000000000000000 R15: ffff96cfc3ce0360
[38.987146] FS:  00007f11c15218c0(0000) GS:ffff96d6dfb00000(0000) knlGS:0000000000000000
[38.988662] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[38.989398] CR2: 00007ffc922c8e60 CR3: 00000001147a6001 CR4: 0000000000370ee0
[38.990279] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[38.991219] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[38.992528] Call Trace:
[38.992854]  <TASK>
[38.993148]  btrfs_relocate_chunk+0x27/0xe0 [btrfs]
[38.993941]  btrfs_balance+0x78e/0xea0 [btrfs]
[38.994801]  ? vsnprintf+0x33c/0x520
[38.995368]  ? __kmalloc_track_caller+0x351/0x440
[38.996198]  btrfs_ioctl_balance+0x2b9/0x3a0 [btrfs]
[38.997084]  btrfs_ioctl+0x11b0/0x2da0 [btrfs]
[38.997867]  ? mod_objcg_state+0xee/0x340
[38.998552]  ? seq_release+0x24/0x30
[38.999184]  ? proc_nr_files+0x30/0x30
[38.999654]  ? call_rcu+0xc8/0x2f0
[39.000228]  ? __x64_sys_ioctl+0x84/0xc0
[39.000872]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
[39.001973]  __x64_sys_ioctl+0x84/0xc0
[39.002566]  do_syscall_64+0x3a/0x80
[39.003011]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[39.003735] RIP: 0033:0x7f11c166959b
[39.007324] RSP: 002b:00007fff2543e998 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[39.008521] RAX: ffffffffffffffda RBX: 00007f11c1521698 RCX: 00007f11c166959b
[39.009833] RDX: 00007fff2543ea40 RSI: 00000000c4009420 RDI: 0000000000000003
[39.011270] RBP: 0000000000000003 R08: 0000000000000013 R09: 00007f11c16f94e0
[39.012581] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff25440df3
[39.014046] R13: 0000000000000000 R14: 00007fff2543ea40 R15: 0000000000000001
[39.015040]  </TASK>
[39.015418] ---[ end trace 0000000000000000 ]---
[43.131559] ------------[ cut here ]------------
[43.132234] kernel BUG at fs/btrfs/extent-tree.c:2717!
[43.133031] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[43.133702] CPU: 1 PID: 1839 Comm: btrfs Tainted: G        W         5.17.0-rc4 #54
[43.134863] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[43.136426] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs]
[43.139913] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246
[43.140629] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001
[43.141604] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff
[43.142645] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50
[43.143669] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000
[43.144657] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000
[43.145686] FS:  00007f7657dd68c0(0000) GS:ffff96d6df640000(0000) knlGS:0000000000000000
[43.146808] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[43.147584] CR2: 00007f7fe81bf5b0 CR3: 00000001093ee004 CR4: 0000000000370ee0
[43.148589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[43.149581] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[43.150559] Call Trace:
[43.150904]  <TASK>
[43.151253]  btrfs_finish_extent_commit+0x88/0x290 [btrfs]
[43.152127]  btrfs_commit_transaction+0x74f/0xaa0 [btrfs]
[43.152932]  ? btrfs_attach_transaction_barrier+0x1e/0x50 [btrfs]
[43.153786]  btrfs_ioctl+0x1edc/0x2da0 [btrfs]
[43.154475]  ? __check_object_size+0x150/0x170
[43.155170]  ? preempt_count_add+0x49/0xa0
[43.155753]  ? __x64_sys_ioctl+0x84/0xc0
[43.156437]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
[43.157456]  __x64_sys_ioctl+0x84/0xc0
[43.157980]  do_syscall_64+0x3a/0x80
[43.158543]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[43.159231] RIP: 0033:0x7f7657f1e59b
[43.161819] RSP: 002b:00007ffda5cd1658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[43.162702] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f7657f1e59b
[43.163526] RDX: 0000000000000000 RSI: 0000000000009408 RDI: 0000000000000003
[43.164358] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
[43.165208] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[43.166029] R13: 00005621b91c3232 R14: 00005621b91ba580 R15: 00007ffda5cd1800
[43.166863]  </TASK>
[43.167125] Modules linked in: btrfs blake2b_generic xor pata_acpi ata_piix libata raid6_pq scsi_mod libcrc32c virtio_net virtio_rng net_failover rng_core failover scsi_common
[43.169552] ---[ end trace 0000000000000000 ]---
[43.171226] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs]
[43.174767] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246
[43.175600] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001
[43.176468] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff
[43.177357] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50
[43.178271] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000
[43.179178] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000
[43.180071] FS:  00007f7657dd68c0(0000) GS:ffff96d6df800000(0000) knlGS:0000000000000000
[43.181073] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[43.181808] CR2: 00007fe09905f010 CR3: 00000001093ee004 CR4: 0000000000370ee0
[43.182706] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[43.183591] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

We first hit the WARN_ON(rc->block_group->pinned > 0) in
btrfs_relocate_block_group() and then the BUG_ON(!cache) in
unpin_extent_range(). This tells us that we are exiting relocation and
removing the block group with bytes still pinned for that block group.
This is supposed to be impossible: the last thing relocate_block_group()
does is commit the transaction to get rid of pinned extents.

Commit d0c2f4f ("btrfs: make concurrent fsyncs wait less when
waiting for a transaction commit") introduced an optimization so that
commits from fsync don't have to wait for the previous commit to unpin
extents. This was only intended to affect fsync, but it inadvertently
made it possible for any commit to skip waiting for the previous commit
to unpin. This is because if a call to btrfs_commit_transaction() finds
that another thread is already committing the transaction, it waits for
the other thread to complete the commit and then returns. If that other
thread was in fsync, then it completes the commit without completing the
previous commit. This makes the following sequence of events possible:

Thread 1____________________|Thread 2 (fsync)_____________________|Thread 3 (balance)___________________
btrfs_commit_transaction(N) |                                     |
  btrfs_run_delayed_refs    |                                     |
    pin extents             |                                     |
  ...                       |                                     |
  state = UNBLOCKED         |btrfs_sync_file                      |
                            |  btrfs_start_transaction(N + 1)     |relocate_block_group
                            |                                     |  btrfs_join_transaction(N + 1)
                            |  btrfs_commit_transaction(N + 1)    |
  ...                       |  trans->state = COMMIT_START        |
                            |                                     |  btrfs_commit_transaction(N + 1)
                            |                                     |    wait_for_commit(N + 1, COMPLETED)
                            |  wait_for_commit(N, SUPER_COMMITTED)|
  state = SUPER_COMMITTED   |  ...                                |
  btrfs_finish_extent_commit|                                     |
    unpin_extent_range()    |  trans->state = COMPLETED           |
                            |                                     |    return
                            |                                     |
    ...                     |                                     |Thread 1 isn't done, so pinned > 0
                            |                                     |and we WARN
                            |                                     |
                            |                                     |btrfs_remove_block_group
    unpin_extent_range()    |                                     |
      Thread 3 removed the  |                                     |
      block group, so we BUG|                                     |

There are other sequences involving SUPER_COMMITTED transactions that
can cause a similar outcome.

We could fix this by making relocation explicitly wait for unpinning,
but there may be other cases that need it. Josef mentioned ENOSPC
flushing and the free space cache inode as other potential victims.
Rather than playing whack-a-mole, this fix is conservative and makes all
commits not in fsync wait for all previous transactions, which is what
the optimization intended.

Fixes: d0c2f4f ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request May 20, 2022
Ido Schimmel says:

====================
selftests: mlxsw: A couple of fixes

Patch #1 fixes a breakage due to a change in iproute2 output. The real
problem is not iproute2, but the fact that the check was not strict
enough. Fixed by using JSON output instead. Targeting at net so that the
test will pass as part of old and new kernels regardless of iproute2
version.

Patch #2 fixes an issue uncovered by the first one.
====================

Link: https://lore.kernel.org/r/20220302161447.217447-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request May 20, 2022
A page fault was encountered in mpt3sas on a LUN reset error path:

[  145.763216] mpt3sas_cm1: Task abort tm failed: handle(0x0002),timeout(30) tr_method(0x0) smid(3) msix_index(0)
[  145.778932] scsi 1:0:0:0: task abort: FAILED scmd(0x0000000024ba29a2)
[  145.817307] scsi 1:0:0:0: attempting device reset! scmd(0x0000000024ba29a2)
[  145.827253] scsi 1:0:0:0: [sg1] tag#2 CDB: Receive Diagnostic 1c 01 01 ff fc 00
[  145.837617] scsi target1:0:0: handle(0x0002), sas_address(0x500605b0000272b9), phy(0)
[  145.848598] scsi target1:0:0: enclosure logical id(0x500605b0000272b8), slot(0)
[  149.858378] mpt3sas_cm1: Poll ReplyDescriptor queues for completion of smid(0), task_type(0x05), handle(0x0002)
[  149.875202] BUG: unable to handle page fault for address: 00000007fffc445d
[  149.885617] #PF: supervisor read access in kernel mode
[  149.894346] #PF: error_code(0x0000) - not-present page
[  149.903123] PGD 0 P4D 0
[  149.909387] Oops: 0000 [#1] PREEMPT SMP NOPTI
[  149.917417] CPU: 24 PID: 3512 Comm: scsi_eh_1 Kdump: loaded Tainted: G S         O      5.10.89-altav-1 #1
[  149.934327] Hardware name: DDN           200NVX2             /200NVX2-MB          , BIOS ATHG2.2.02.01 09/10/2021
[  149.951871] RIP: 0010:_base_process_reply_queue+0x4b/0x900 [mpt3sas]
[  149.961889] Code: 0f 84 22 02 00 00 8d 48 01 49 89 fd 48 8d 57 38 f0 0f b1 4f 38 0f 85 d8 01 00 00 49 8b 45 10 45 31 e4 41 8b 55 0c 48 8d 1c d0 <0f> b6 03 83 e0 0f 3c 0f 0f 85 a2 00 00 00 e9 e6 01 00 00 0f b7 ee
[  149.991952] RSP: 0018:ffffc9000f1ebcb8 EFLAGS: 00010246
[  150.000937] RAX: 0000000000000055 RBX: 00000007fffc445d RCX: 000000002548f071
[  150.011841] RDX: 00000000ffff8881 RSI: 0000000000000001 RDI: ffff888125ed50d8
[  150.022670] RBP: 0000000000000000 R08: 0000000000000000 R09: c0000000ffff7fff
[  150.033445] R10: ffffc9000f1ebb68 R11: ffffc9000f1ebb60 R12: 0000000000000000
[  150.044204] R13: ffff888125ed50d8 R14: 0000000000000080 R15: 34cdc00034cdea80
[  150.054963] FS:  0000000000000000(0000) GS:ffff88dfaf200000(0000) knlGS:0000000000000000
[  150.066715] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  150.076078] CR2: 00000007fffc445d CR3: 000000012448a006 CR4: 0000000000770ee0
[  150.086887] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  150.097670] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  150.108323] PKRU: 55555554
[  150.114690] Call Trace:
[  150.120497]  ? printk+0x48/0x4a
[  150.127049]  mpt3sas_scsih_issue_tm.cold.114+0x2e/0x2b3 [mpt3sas]
[  150.136453]  mpt3sas_scsih_issue_locked_tm+0x86/0xb0 [mpt3sas]
[  150.145759]  scsih_dev_reset+0xea/0x300 [mpt3sas]
[  150.153891]  scsi_eh_ready_devs+0x541/0x9e0 [scsi_mod]
[  150.162206]  ? __scsi_host_match+0x20/0x20 [scsi_mod]
[  150.170406]  ? scsi_try_target_reset+0x90/0x90 [scsi_mod]
[  150.178925]  ? blk_mq_tagset_busy_iter+0x45/0x60
[  150.186638]  ? scsi_try_target_reset+0x90/0x90 [scsi_mod]
[  150.195087]  scsi_error_handler+0x3a5/0x4a0 [scsi_mod]
[  150.203206]  ? __schedule+0x1e9/0x610
[  150.209783]  ? scsi_eh_get_sense+0x210/0x210 [scsi_mod]
[  150.217924]  kthread+0x12e/0x150
[  150.224041]  ? kthread_worker_fn+0x130/0x130
[  150.231206]  ret_from_fork+0x1f/0x30

This is caused by mpt3sas_base_sync_reply_irqs() using an invalid reply_q
pointer outside of the list_for_each_entry() loop. At the end of the full
list traversal the pointer is invalid.

Move the _base_process_reply_queue() call inside of the loop.

Link: https://lore.kernel.org/r/d625deae-a958-0ace-2ba3-0888dd0a415b@ddn.com
Fixes: 711a923 ("scsi: mpt3sas: Postprocessing of target and LUN reset")
Cc: stable@vger.kernel.org
Acked-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Matt Lupfer <mlupfer@ddn.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
akemnade pushed a commit that referenced this pull request May 20, 2022
The commit in Fixes started adding INT3 after RETs as a mitigation
against straight-line speculation.

The fastop SETcc implementation in kvm's insn emulator uses macro magic
to generate all possible SETcc functions and to jump to them when
emulating the respective instruction.

However, it hardcodes the size and alignment of those functions to 4: a
three-byte SETcc insn and a single-byte RET. BUT, with SLS, there's an
INT3 that gets slapped after the RET, which brings the whole scheme out
of alignment:

  15:   0f 90 c0                seto   %al
  18:   c3                      ret
  19:   cc                      int3
  1a:   0f 1f 00                nopl   (%rax)
  1d:   0f 91 c0                setno  %al
  20:   c3                      ret
  21:   cc                      int3
  22:   0f 1f 00                nopl   (%rax)
  25:   0f 92 c0                setb   %al
  28:   c3                      ret
  29:   cc                      int3

and this explodes like this:

  int3: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 2435 Comm: qemu-system-x86 Not tainted 5.17.0-rc8-sls #1
  Hardware name: Dell Inc. Precision WorkStation T3400  /0TP412, BIOS A14 04/30/2012
  RIP: 0010:setc+0x5/0x8 [kvm]
  Code: 00 00 0f 1f 00 0f b6 05 43 24 06 00 c3 cc 0f 1f 80 00 00 00 00 0f 90 c0 c3 cc 0f \
	  1f 00 0f 91 c0 c3 cc 0f 1f 00 0f 92 c0 c3 cc <0f> 1f 00 0f 93 c0 c3 cc 0f 1f 00 \
	  0f 94 c0 c3 cc 0f 1f 00 0f 95 c0
  Call Trace:
   <TASK>
   ? x86_emulate_insn [kvm]
   ? x86_emulate_instruction [kvm]
   ? vmx_handle_exit [kvm_intel]
   ? kvm_arch_vcpu_ioctl_run [kvm]
   ? kvm_vcpu_ioctl [kvm]
   ? __x64_sys_ioctl
   ? do_syscall_64
   ? entry_SYSCALL_64_after_hwframe
   </TASK>

Raise the alignment value when SLS is enabled and use a macro for that
instead of hard-coding naked numbers.

Fixes: e463a09 ("x86: Add straight-line-speculation mitigation")
Reported-by: Jamie Heilman <jamie@audible.transient.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Jamie Heilman <jamie@audible.transient.net>
Link: https://lore.kernel.org/r/YjGzJwjrvxg5YZ0Z@audible.transient.net
[Add a comment and a bit of safety checking, since this is going to be changed
 again for IBT support. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Currently, RISC-V sets up reserved memory using the "early" copy of the
device tree. As a result, when trying to get a reserved memory region
using of_reserved_mem_lookup(), the pointer to reserved memory regions
is using the early, pre-virtual-memory address which causes a kernel
panic when trying to use the buffer's name:

 Unable to handle kernel paging request at virtual address 00000000401c31ac
 Oops [#1]
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 6.0.0-rc1-00001-g0d9d6953d834 #1
 Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
 epc : string+0x4a/0xea
  ra : vsnprintf+0x1e4/0x336
 epc : ffffffff80335ea0 ra : ffffffff80338936 sp : ffffffff81203be0
  gp : ffffffff812e0a98 tp : ffffffff8120de40 t0 : 0000000000000000
  t1 : ffffffff81203e28 t2 : 7265736572203a46 s0 : ffffffff81203c20
  s1 : ffffffff81203e28 a0 : ffffffff81203d22 a1 : 0000000000000000
  a2 : ffffffff81203d08 a3 : 0000000081203d21 a4 : ffffffffffffffff
  a5 : 00000000401c31ac a6 : ffff0a00ffffff04 a7 : ffffffffffffffff
  s2 : ffffffff81203d08 s3 : ffffffff81203d00 s4 : 0000000000000008
  s5 : ffffffff000000ff s6 : 0000000000ffffff s7 : 00000000ffffff00
  s8 : ffffffff80d9821a s9 : ffffffff81203d22 s10: 0000000000000002
  s11: ffffffff80d9821c t3 : ffffffff812f3617 t4 : ffffffff812f3617
  t5 : ffffffff812f3618 t6 : ffffffff81203d08
 status: 0000000200000100 badaddr: 00000000401c31ac cause: 000000000000000d
 [<ffffffff80338936>] vsnprintf+0x1e4/0x336
 [<ffffffff80055ae2>] vprintk_store+0xf6/0x344
 [<ffffffff80055d86>] vprintk_emit+0x56/0x192
 [<ffffffff80055ed8>] vprintk_default+0x16/0x1e
 [<ffffffff800563d2>] vprintk+0x72/0x80
 [<ffffffff806813b2>] _printk+0x36/0x50
 [<ffffffff8068af48>] print_reserved_mem+0x1c/0x24
 [<ffffffff808057ec>] paging_init+0x528/0x5bc
 [<ffffffff808031ae>] setup_arch+0xd0/0x592
 [<ffffffff8080070e>] start_kernel+0x82/0x73c

early_init_fdt_scan_reserved_mem() takes no arguments as it operates on
initial_boot_params, which is populated by early_init_dt_verify(). On
RISC-V, early_init_dt_verify() is called twice. Once, directly, in
setup_arch() if CONFIG_BUILTIN_DTB is not enabled and once indirectly,
very early in the boot process, by parse_dtb() when it calls
early_init_dt_scan_nodes().

This first call uses dtb_early_va to set initial_boot_params, which is
not usable later in the boot process when
early_init_fdt_scan_reserved_mem() is called. On arm64 for example, the
corresponding call to early_init_dt_scan_nodes() uses fixmap addresses
and doesn't suffer the same fate.

Move early_init_fdt_scan_reserved_mem() further along the boot sequence,
after the direct call to early_init_dt_verify() in setup_arch() so that
the names use the correct virtual memory addresses. The above supposed
that CONFIG_BUILTIN_DTB was not set, but should work equally in the case
where it is - unflatted_and_copy_device_tree() also updates
initial_boot_params.

Reported-by: Valentina Fernandez <valentina.fernandezalanis@microchip.com>
Reported-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/linux-riscv/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Fixes: 922b037 ("riscv: Fix memblock reservation for device tree blob")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/r/20221107151524.3941467-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
…x/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - Force the use of SetVirtualAddressMap() on Ampera Altra arm64
   machines, which crash in SetTime() if no virtual remapping is used

   This is the first time we've added an SMBIOS based quirk on arm64,
   but fortunately, we can just call a EFI protocol to grab the type #1
   SMBIOS record when running in the stub, so we don't need all the
   machinery we have in the kernel proper to parse SMBIOS data.

 - Drop a spurious warning on misaligned runtime regions when using 16k
   or 64k pages on arm64

* tag 'efi-fixes-for-v6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  arm64: efi: Fix handling of misaligned runtime regions and drop warning
  arm64: efi: Force the use of SetVirtualAddressMap() on Altra machines
akemnade pushed a commit that referenced this pull request Dec 24, 2022
When doing a nowait buffered write we can trigger the following assertion:

[11138.437027] assertion failed: !path->nowait, in fs/btrfs/ctree.c:4658
[11138.438251] ------------[ cut here ]------------
[11138.438254] kernel BUG at fs/btrfs/messages.c:259!
[11138.438762] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
[11138.439450] CPU: 4 PID: 1091021 Comm: fsstress Not tainted 6.1.0-rc4-btrfs-next-128 #1
[11138.440611] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[11138.442553] RIP: 0010:btrfs_assertfail+0x19/0x1b [btrfs]
[11138.443583] Code: 5b 41 5a 41 (...)
[11138.446437] RSP: 0018:ffffbaf0cf05b840 EFLAGS: 00010246
[11138.447235] RAX: 0000000000000039 RBX: ffffbaf0cf05b938 RCX: 0000000000000000
[11138.448303] RDX: 0000000000000000 RSI: ffffffffb2ef59f6 RDI: 00000000ffffffff
[11138.449370] RBP: ffff9165f581eb68 R08: 00000000ffffffff R09: 0000000000000001
[11138.450493] R10: ffff9167a88421f8 R11: 0000000000000000 R12: ffff9164981b1000
[11138.451661] R13: 000000008c8f1000 R14: ffff9164991d4000 R15: ffff9164981b1000
[11138.452225] FS:  00007f1438a66440(0000) GS:ffff9167ad600000(0000) knlGS:0000000000000000
[11138.452949] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[11138.453394] CR2: 00007f1438a64000 CR3: 0000000100c36002 CR4: 0000000000370ee0
[11138.454057] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[11138.454879] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[11138.455779] Call Trace:
[11138.456211]  <TASK>
[11138.456598]  btrfs_next_old_leaf.cold+0x18/0x1d [btrfs]
[11138.457827]  ? kmem_cache_alloc+0x18d/0x2a0
[11138.458516]  btrfs_lookup_csums_range+0x149/0x4d0 [btrfs]
[11138.459407]  csum_exist_in_range+0x56/0x110 [btrfs]
[11138.460271]  can_nocow_file_extent+0x27c/0x310 [btrfs]
[11138.461155]  can_nocow_extent+0x1ec/0x2e0 [btrfs]
[11138.461672]  btrfs_check_nocow_lock+0x114/0x1c0 [btrfs]
[11138.462951]  btrfs_buffered_write+0x44c/0x8e0 [btrfs]
[11138.463482]  btrfs_do_write_iter+0x42b/0x5f0 [btrfs]
[11138.463982]  ? lock_release+0x153/0x4a0
[11138.464347]  io_write+0x11b/0x570
[11138.464660]  ? lock_release+0x153/0x4a0
[11138.465213]  ? lock_is_held_type+0xe8/0x140
[11138.466003]  io_issue_sqe+0x63/0x4a0
[11138.466339]  io_submit_sqes+0x238/0x770
[11138.466741]  __do_sys_io_uring_enter+0x37b/0xb10
[11138.467206]  ? lock_is_held_type+0xe8/0x140
[11138.467879]  ? syscall_enter_from_user_mode+0x1d/0x50
[11138.468688]  do_syscall_64+0x38/0x90
[11138.469265]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[11138.470017] RIP: 0033:0x7f1438c539e6

This is because to check if we can NOCOW, we check that if we can NOCOW
into an extent (it's prealloc extent or the inode has NOCOW attribute),
and then check if there are csums for the extent's range in the csum tree.
The search may leave us beyond the last slot of a leaf, and then when
we call btrfs_next_leaf() we end up at btrfs_next_old_leaf() with a
time_seq of 0.

This triggers a failure of the first assertion at btrfs_next_old_leaf(),
since we have a nowait path. With assertions disabled, we simply don't
respect the NOWAIT semantics, allowing the write to block on locks or
blocking on IO for reading an extent buffer from disk.

Fix this by:

1) Triggering the assertion only if time_seq is not 0, which means that
   search is being done by a tree mod log user, and in the buffered and
   direct IO write paths we don't use the tree mod log;

2) Implementing NOWAIT semantics at btrfs_next_old_leaf(). Any failure to
   lock an extent buffer should return immediately and not retry the
   search, as well as if we need to do IO to read an extent buffer from
   disk.

Fixes: c922b01 ("btrfs: assert nowait mode is not used for some btree search functions")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Syzbot reported the following lockdep splat

======================================================
WARNING: possible circular locking dependency detected
6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Not tainted
------------------------------------------------------
syz-executor307/3029 is trying to acquire lock:
ffff0000c02525d8 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x54/0xb4 mm/memory.c:5576

but task is already holding lock:
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (btrfs-root-00){++++}-{3:3}:
       down_read_nested+0x64/0x84 kernel/locking/rwsem.c:1624
       __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
       btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
       btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279
       btrfs_search_slot_get_root+0x74/0x338 fs/btrfs/ctree.c:1637
       btrfs_search_slot+0x1b0/0xfd8 fs/btrfs/ctree.c:1944
       btrfs_update_root+0x6c/0x5a0 fs/btrfs/root-tree.c:132
       commit_fs_roots+0x1f0/0x33c fs/btrfs/transaction.c:1459
       btrfs_commit_transaction+0x89c/0x12d8 fs/btrfs/transaction.c:2343
       flush_space+0x66c/0x738 fs/btrfs/space-info.c:786
       btrfs_async_reclaim_metadata_space+0x43c/0x4e0 fs/btrfs/space-info.c:1059
       process_one_work+0x2d8/0x504 kernel/workqueue.c:2289
       worker_thread+0x340/0x610 kernel/workqueue.c:2436
       kthread+0x12c/0x158 kernel/kthread.c:376
       ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860

-> #2 (&fs_info->reloc_mutex){+.+.}-{3:3}:
       __mutex_lock_common+0xd4/0xca8 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
       btrfs_record_root_in_trans fs/btrfs/transaction.c:516 [inline]
       start_transaction+0x248/0x944 fs/btrfs/transaction.c:752
       btrfs_start_transaction+0x34/0x44 fs/btrfs/transaction.c:781
       btrfs_create_common+0xf0/0x1b4 fs/btrfs/inode.c:6651
       btrfs_create+0x8c/0xb0 fs/btrfs/inode.c:6697
       lookup_open fs/namei.c:3413 [inline]
       open_last_lookups fs/namei.c:3481 [inline]
       path_openat+0x804/0x11c4 fs/namei.c:3688
       do_filp_open+0xdc/0x1b8 fs/namei.c:3718
       do_sys_openat2+0xb8/0x22c fs/open.c:1313
       do_sys_open fs/open.c:1329 [inline]
       __do_sys_openat fs/open.c:1345 [inline]
       __se_sys_openat fs/open.c:1340 [inline]
       __arm64_sys_openat+0xb0/0xe0 fs/open.c:1340
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #1 (sb_internal#2){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1826 [inline]
       sb_start_intwrite include/linux/fs.h:1948 [inline]
       start_transaction+0x360/0x944 fs/btrfs/transaction.c:683
       btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:795
       btrfs_dirty_inode+0x50/0x140 fs/btrfs/inode.c:6103
       btrfs_update_time+0x1c0/0x1e8 fs/btrfs/inode.c:6145
       inode_update_time fs/inode.c:1872 [inline]
       touch_atime+0x1f0/0x4a8 fs/inode.c:1945
       file_accessed include/linux/fs.h:2516 [inline]
       btrfs_file_mmap+0x50/0x88 fs/btrfs/file.c:2407
       call_mmap include/linux/fs.h:2192 [inline]
       mmap_region+0x7fc/0xc14 mm/mmap.c:1752
       do_mmap+0x644/0x97c mm/mmap.c:1540
       vm_mmap_pgoff+0xe8/0x1d0 mm/util.c:552
       ksys_mmap_pgoff+0x1cc/0x278 mm/mmap.c:1586
       __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
       __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
       __arm64_sys_mmap+0x58/0x6c arch/arm64/kernel/sys.c:21
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3095 [inline]
       check_prevs_add kernel/locking/lockdep.c:3214 [inline]
       validate_chain kernel/locking/lockdep.c:3829 [inline]
       __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053
       lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666
       __might_fault+0x7c/0xb4 mm/memory.c:5577
       _copy_to_user include/linux/uaccess.h:134 [inline]
       copy_to_user include/linux/uaccess.h:160 [inline]
       btrfs_ioctl_get_subvol_rootref+0x3a8/0x4bc fs/btrfs/ioctl.c:3203
       btrfs_ioctl+0xa08/0xa64 fs/btrfs/ioctl.c:5556
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl fs/ioctl.c:856 [inline]
       __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
       el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

other info that might help us debug this:

Chain exists of:
  &mm->mmap_lock --> &fs_info->reloc_mutex --> btrfs-root-00

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(btrfs-root-00);
                               lock(&fs_info->reloc_mutex);
                               lock(btrfs-root-00);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz-executor307/3029:
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock fs/btrfs/locking.c:134 [inline]
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_tree_read_lock fs/btrfs/locking.c:140 [inline]
 #0: ffff0000c958a608 (btrfs-root-00){++++}-{3:3}, at: btrfs_read_lock_root_node+0x13c/0x1c0 fs/btrfs/locking.c:279

stack backtrace:
CPU: 0 PID: 3029 Comm: syz-executor307 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156
 show_stack+0x2c/0x54 arch/arm64/kernel/stacktrace.c:163
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2053
 check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3095 [inline]
 check_prevs_add kernel/locking/lockdep.c:3214 [inline]
 validate_chain kernel/locking/lockdep.c:3829 [inline]
 __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053
 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666
 __might_fault+0x7c/0xb4 mm/memory.c:5577
 _copy_to_user include/linux/uaccess.h:134 [inline]
 copy_to_user include/linux/uaccess.h:160 [inline]
 btrfs_ioctl_get_subvol_rootref+0x3a8/0x4bc fs/btrfs/ioctl.c:3203
 btrfs_ioctl+0xa08/0xa64 fs/btrfs/ioctl.c:5556
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
 el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

We do generally the right thing here, copying the references into a
temporary buffer, however we are still holding the path when we do
copy_to_user from the temporary buffer.  Fix this by freeing the path
before we copy to user space.

Reported-by: syzbot+4ef9e52e464c6ff47d9d@syzkaller.appspotmail.com
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
We used to use the wrong type of integer in 'zfcp_fsf_req_send()' to cache
the FSF request ID when sending a new FSF request. This is used in case the
sending fails and we need to remove the request from our internal hash
table again (so we don't keep an invalid reference and use it when we free
the request again).

In 'zfcp_fsf_req_send()' we used to cache the ID as 'int' (signed and 32
bit wide), but the rest of the zfcp code (and the firmware specification)
handles the ID as 'unsigned long'/'u64' (unsigned and 64 bit wide [s390x
ELF ABI]).  For one this has the obvious problem that when the ID grows
past 32 bit (this can happen reasonably fast) it is truncated to 32 bit
when storing it in the cache variable and so doesn't match the original ID
anymore.  The second less obvious problem is that even when the original ID
has not yet grown past 32 bit, as soon as the 32nd bit is set in the
original ID (0x80000000 = 2'147'483'648) we will have a mismatch when we
cast it back to 'unsigned long'. As the cached variable is of a signed
type, the compiler will choose a sign-extending instruction to load the 32
bit variable into a 64 bit register (e.g.: 'lgf %r11,188(%r15)'). So once
we pass the cached variable into 'zfcp_reqlist_find_rm()' to remove the
request again all the leading zeros will be flipped to ones to extend the
sign and won't match the original ID anymore (this has been observed in
practice).

If we can't successfully remove the request from the hash table again after
'zfcp_qdio_send()' fails (this happens regularly when zfcp cannot notify
the adapter about new work because the adapter is already gone during
e.g. a ChpID toggle) we will end up with a double free.  We unconditionally
free the request in the calling function when 'zfcp_fsf_req_send()' fails,
but because the request is still in the hash table we end up with a stale
memory reference, and once the zfcp adapter is either reset during recovery
or shutdown we end up freeing the same memory twice.

The resulting stack traces vary depending on the kernel and have no direct
correlation to the place where the bug occurs. Here are three examples that
have been seen in practice:

  list_del corruption. next->prev should be 00000001b9d13800, but was 00000000dead4ead. (next=00000001bd131a00)
  ------------[ cut here ]------------
  kernel BUG at lib/list_debug.c:62!
  monitor event: 0040 ilc:2 [#1] PREEMPT SMP
  Modules linked in: ...
  CPU: 9 PID: 1617 Comm: zfcperp0.0.1740 Kdump: loaded
  Hardware name: ...
  Krnl PSW : 0704d00180000000 00000003cbeea1f8 (__list_del_entry_valid+0x98/0x140)
             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
  Krnl GPRS: 00000000916d12f1 0000000080000000 000000000000006d 00000003cb665cd6
             0000000000000001 0000000000000000 0000000000000000 00000000d28d21e8
             00000000d3844000 00000380099efd28 00000001bd131a00 00000001b9d13800
             00000000d3290100 0000000000000000 00000003cbeea1f4 00000380099efc70
  Krnl Code: 00000003cbeea1e8: c020004f68a7        larl    %r2,00000003cc8d7336
             00000003cbeea1ee: c0e50027fd65        brasl   %r14,00000003cc3e9cb8
            #00000003cbeea1f4: af000000            mc      0,0
            >00000003cbeea1f8: c02000920440        larl    %r2,00000003cd12aa78
             00000003cbeea1fe: c0e500289c25        brasl   %r14,00000003cc3fda48
             00000003cbeea204: b9040043            lgr     %r4,%r3
             00000003cbeea208: b9040051            lgr     %r5,%r1
             00000003cbeea20c: b9040032            lgr     %r3,%r2
  Call Trace:
   [<00000003cbeea1f8>] __list_del_entry_valid+0x98/0x140
  ([<00000003cbeea1f4>] __list_del_entry_valid+0x94/0x140)
   [<000003ff7ff502fe>] zfcp_fsf_req_dismiss_all+0xde/0x150 [zfcp]
   [<000003ff7ff49cd0>] zfcp_erp_strategy_do_action+0x160/0x280 [zfcp]
   [<000003ff7ff4a22e>] zfcp_erp_strategy+0x21e/0xca0 [zfcp]
   [<000003ff7ff4ad34>] zfcp_erp_thread+0x84/0x1a0 [zfcp]
   [<00000003cb5eece8>] kthread+0x138/0x150
   [<00000003cb557f3c>] __ret_from_fork+0x3c/0x60
   [<00000003cc4172ea>] ret_from_fork+0xa/0x40
  INFO: lockdep is turned off.
  Last Breaking-Event-Address:
   [<00000003cc3e9d04>] _printk+0x4c/0x58
  Kernel panic - not syncing: Fatal exception: panic_on_oops

or:

  Unable to handle kernel pointer dereference in virtual kernel address space
  Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6803
  Fault in home space mode while using kernel ASCE.
  AS:0000000063b10007 R3:0000000000000024
  Oops: 0038 ilc:3 [#1] SMP
  Modules linked in: ...
  CPU: 10 PID: 0 Comm: swapper/10 Kdump: loaded
  Hardware name: ...
  Krnl PSW : 0404d00180000000 000003ff7febaf8e (zfcp_fsf_reqid_check+0x86/0x158 [zfcp])
             R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
  Krnl GPRS: 5a6f1cfa89c49ac3 00000000aff2c4c8 6b6b6b6b6b6b6b6b 00000000000002a8
             0000000000000000 0000000000000055 0000000000000000 00000000a8515800
             0700000000000000 00000000a6e14500 00000000aff2c000 000000008003c44c
             000000008093c700 0000000000000010 00000380009ebba8 00000380009ebb48
  Krnl Code: 000003ff7febaf7e: a7f4003d            brc     15,000003ff7febaff8
             000003ff7febaf82: e32020000004        lg      %r2,0(%r2)
            #000003ff7febaf88: ec2100388064        cgrj    %r2,%r1,8,000003ff7febaff8
            >000003ff7febaf8e: e3b020100020        cg      %r11,16(%r2)
             000003ff7febaf94: a774fff7            brc     7,000003ff7febaf82
             000003ff7febaf98: ec280030007c        cgij    %r2,0,8,000003ff7febaff8
             000003ff7febaf9e: e31020080004        lg      %r1,8(%r2)
             000003ff7febafa4: e33020000004        lg      %r3,0(%r2)
  Call Trace:
   [<000003ff7febaf8e>] zfcp_fsf_reqid_check+0x86/0x158 [zfcp]
   [<000003ff7febbdbc>] zfcp_qdio_int_resp+0x6c/0x170 [zfcp]
   [<000003ff7febbf90>] zfcp_qdio_irq_tasklet+0xd0/0x108 [zfcp]
   [<0000000061d90a04>] tasklet_action_common.constprop.0+0xdc/0x128
   [<000000006292f300>] __do_softirq+0x130/0x3c0
   [<0000000061d906c6>] irq_exit_rcu+0xfe/0x118
   [<000000006291e818>] do_io_irq+0xc8/0x168
   [<000000006292d516>] io_int_handler+0xd6/0x110
   [<000000006292d596>] psw_idle_exit+0x0/0xa
  ([<0000000061d3be50>] arch_cpu_idle+0x40/0xd0)
   [<000000006292ceea>] default_idle_call+0x52/0xf8
   [<0000000061de4fa4>] do_idle+0xd4/0x168
   [<0000000061de51fe>] cpu_startup_entry+0x36/0x40
   [<0000000061d4faac>] smp_start_secondary+0x12c/0x138
   [<000000006292d88e>] restart_int_handler+0x6e/0x90
  Last Breaking-Event-Address:
   [<000003ff7febaf94>] zfcp_fsf_reqid_check+0x8c/0x158 [zfcp]
  Kernel panic - not syncing: Fatal exception in interrupt

or:

  Unable to handle kernel pointer dereference in virtual kernel address space
  Failing address: 523b05d3ae76a000 TEID: 523b05d3ae76a803
  Fault in home space mode while using kernel ASCE.
  AS:0000000077c40007 R3:0000000000000024
  Oops: 0038 ilc:3 [#1] SMP
  Modules linked in: ...
  CPU: 3 PID: 453 Comm: kworker/3:1H Kdump: loaded
  Hardware name: ...
  Workqueue: kblockd blk_mq_run_work_fn
  Krnl PSW : 0404d00180000000 0000000076fc0312 (__kmalloc+0xd2/0x398)
             R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
  Krnl GPRS: ffffffffffffffff 523b05d3ae76abf6 0000000000000000 0000000000092a20
             0000000000000002 00000007e49b5cc0 00000007eda8f000 0000000000092a20
             00000007eda8f000 00000003b02856b9 00000000000000a8 523b05d3ae76abf6
             00000007dd662000 00000007eda8f000 0000000076fc02b2 000003e0037637a0
  Krnl Code: 0000000076fc0302: c004000000d4	brcl	0,76fc04aa
             0000000076fc0308: b904001b		lgr	%r1,%r11
            #0000000076fc030c: e3106020001a	algf	%r1,32(%r6)
            >0000000076fc0312: e31010000082	xg	%r1,0(%r1)
             0000000076fc0318: b9040001		lgr	%r0,%r1
             0000000076fc031c: e30061700082	xg	%r0,368(%r6)
             0000000076fc0322: ec59000100d9	aghik	%r5,%r9,1
             0000000076fc0328: e34003b80004	lg	%r4,952
  Call Trace:
   [<0000000076fc0312>] __kmalloc+0xd2/0x398
   [<0000000076f318f2>] mempool_alloc+0x72/0x1f8
   [<000003ff8027c5f8>] zfcp_fsf_req_create.isra.7+0x40/0x268 [zfcp]
   [<000003ff8027f1bc>] zfcp_fsf_fcp_cmnd+0xac/0x3f0 [zfcp]
   [<000003ff80280f1a>] zfcp_scsi_queuecommand+0x122/0x1d0 [zfcp]
   [<000003ff800b4218>] scsi_queue_rq+0x778/0xa10 [scsi_mod]
   [<00000000771782a0>] __blk_mq_try_issue_directly+0x130/0x208
   [<000000007717a124>] blk_mq_request_issue_directly+0x4c/0xa8
   [<000003ff801302e2>] dm_mq_queue_rq+0x2ea/0x468 [dm_mod]
   [<0000000077178c12>] blk_mq_dispatch_rq_list+0x33a/0x818
   [<000000007717f064>] __blk_mq_do_dispatch_sched+0x284/0x2f0
   [<000000007717f44c>] __blk_mq_sched_dispatch_requests+0x1c4/0x218
   [<000000007717fa7a>] blk_mq_sched_dispatch_requests+0x52/0x90
   [<0000000077176d74>] __blk_mq_run_hw_queue+0x9c/0xc0
   [<0000000076da6d74>] process_one_work+0x274/0x4d0
   [<0000000076da7018>] worker_thread+0x48/0x560
   [<0000000076daef18>] kthread+0x140/0x160
   [<000000007751d144>] ret_from_fork+0x28/0x30
  Last Breaking-Event-Address:
   [<0000000076fc0474>] __kmalloc+0x234/0x398
  Kernel panic - not syncing: Fatal exception: panic_on_oops

To fix this, simply change the type of the cache variable to 'unsigned
long', like the rest of zfcp and also the argument for
'zfcp_reqlist_find_rm()'. This prevents truncation and wrong sign extension
and so can successfully remove the request from the hash table.

Fixes: e60a6d6 ("[SCSI] zfcp: Remove function zfcp_reqlist_find_safe")
Cc: <stable@vger.kernel.org> #v2.6.34+
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Link: https://lore.kernel.org/r/979f6e6019d15f91ba56182f1aaf68d61bf37fc6.1668595505.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
The @ftrace_mod is allocated by kzalloc(), so both the members {prev,next}
of @ftrace_mode->list are NULL, it's not a valid state to call list_del().
If kstrdup() for @ftrace_mod->{func|module} fails, it goes to @out_free
tag and calls free_ftrace_mod() to destroy @ftrace_mod, then list_del()
will write prev->next and next->prev, where null pointer dereference
happens.

BUG: kernel NULL pointer dereference, address: 0000000000000008
Oops: 0002 [#1] PREEMPT SMP NOPTI
Call Trace:
 <TASK>
 ftrace_mod_callback+0x20d/0x220
 ? do_filp_open+0xd9/0x140
 ftrace_process_regex.isra.51+0xbf/0x130
 ftrace_regex_write.isra.52.part.53+0x6e/0x90
 vfs_write+0xee/0x3a0
 ? __audit_filter_op+0xb1/0x100
 ? auditd_test_task+0x38/0x50
 ksys_write+0xa5/0xe0
 do_syscall_64+0x3a/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
Kernel panic - not syncing: Fatal exception

So call INIT_LIST_HEAD() to initialize the list member to fix this issue.

Link: https://lkml.kernel.org/r/20221116015207.30858-1-xiujianfeng@huawei.com

Cc: stable@vger.kernel.org
Fixes: 673feb9 ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
In register_synth_event(), if set_synth_event_print_fmt() failed, then
both trace_remove_event_call() and unregister_trace_event() will be
called, which means the trace_event_call will call
__unregister_trace_event() twice. As the result, the second unregister
will causes the wild-memory-access.

register_synth_event
    set_synth_event_print_fmt failed
    trace_remove_event_call
        event_remove
            if call->event.funcs then
            __unregister_trace_event (first call)
    unregister_trace_event
        __unregister_trace_event (second call)

Fix the bug by avoiding to call the second __unregister_trace_event() by
checking if the first one is called.

general protection fault, probably for non-canonical address
	0xfbd59c0000000024: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range
[0xdead000000000120-0xdead000000000127]
CPU: 0 PID: 3807 Comm: modprobe Not tainted
6.1.0-rc1-00186-g76f33a7eedb4 #299
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:unregister_trace_event+0x6e/0x280
Code: 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 0e 02 00 00 48
b8 00 00 00 00 00 fc ff df 4c 8b 63 08 4c 89 e2 48 c1 ea 03 <80> 3c 02
00 0f 85 e2 01 00 00 49 89 2c 24 48 85 ed 74 28 e8 7a 9b
RSP: 0018:ffff88810413f370 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffff888105d050b0 RCX: 0000000000000000
RDX: 1bd5a00000000024 RSI: ffff888119e276e0 RDI: ffffffff835a8b20
RBP: dead000000000100 R08: 0000000000000000 R09: fffffbfff0913481
R10: ffffffff8489a407 R11: fffffbfff0913480 R12: dead000000000122
R13: ffff888105d050b8 R14: 0000000000000000 R15: ffff888105d05028
FS:  00007f7823e8d540(0000) GS:ffff888119e00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7823e7ebec CR3: 000000010a058002 CR4: 0000000000330ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __create_synth_event+0x1e37/0x1eb0
 create_or_delete_synth_event+0x110/0x250
 synth_event_run_command+0x2f/0x110
 test_gen_synth_cmd+0x170/0x2eb [synth_event_gen_test]
 synth_event_gen_test_init+0x76/0x9bc [synth_event_gen_test]
 do_one_initcall+0xdb/0x480
 do_init_module+0x1cf/0x680
 load_module+0x6a50/0x70a0
 __do_sys_finit_module+0x12f/0x1c0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Link: https://lkml.kernel.org/r/20221117012346.22647-3-shangxiaojing@huawei.com

Fixes: 4b14793 ("tracing: Add support for 'synthetic' events")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Cc: stable@vger.kernel.org
Cc: <mhiramat@kernel.org>
Cc: <zanussi@kernel.org>
Cc: <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
When logging an inode in full mode, or when logging xattrs or when logging
the dir index items of a directory, we are modifying the log tree while
holding a read lock on a leaf from the fs/subvolume tree. This can lead to
a deadlock in rare circumstances, but it is a real possibility, and it was
recently reported by syzbot with the following trace from lockdep:

   WARNING: possible circular locking dependency detected
   6.1.0-rc5-next-20221116-syzkaller #0 Not tainted
   ------------------------------------------------------
   syz-executor.1/16154 is trying to acquire lock:
   ffff88807e3084a0 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0xa1/0xf30 fs/btrfs/delayed-inode.c:256

   but task is already holding lock:
   ffff88807df33078 (btrfs-log-00){++++}-{3:3}, at: __btrfs_tree_lock+0x32/0x3d0 fs/btrfs/locking.c:197

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #2 (btrfs-log-00){++++}-{3:3}:
          down_read_nested+0x9e/0x450 kernel/locking/rwsem.c:1634
          __btrfs_tree_read_lock+0x32/0x350 fs/btrfs/locking.c:135
          btrfs_tree_read_lock fs/btrfs/locking.c:141 [inline]
          btrfs_read_lock_root_node+0x82/0x3a0 fs/btrfs/locking.c:280
          btrfs_search_slot_get_root fs/btrfs/ctree.c:1678 [inline]
          btrfs_search_slot+0x3ca/0x2c70 fs/btrfs/ctree.c:1998
          btrfs_lookup_csum+0x116/0x3f0 fs/btrfs/file-item.c:209
          btrfs_csum_file_blocks+0x40e/0x1370 fs/btrfs/file-item.c:1021
          log_csums.isra.0+0x244/0x2d0 fs/btrfs/tree-log.c:4258
          copy_items.isra.0+0xbfb/0xed0 fs/btrfs/tree-log.c:4403
          copy_inode_items_to_log+0x13d6/0x1d90 fs/btrfs/tree-log.c:5873
          btrfs_log_inode+0xb19/0x4680 fs/btrfs/tree-log.c:6495
          btrfs_log_inode_parent+0x890/0x2a20 fs/btrfs/tree-log.c:6982
          btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7083
          btrfs_sync_file+0xa41/0x13c0 fs/btrfs/file.c:1921
          vfs_fsync_range+0x13e/0x230 fs/sync.c:188
          generic_write_sync include/linux/fs.h:2856 [inline]
          iomap_dio_complete+0x73a/0x920 fs/iomap/direct-io.c:128
          btrfs_direct_write fs/btrfs/file.c:1536 [inline]
          btrfs_do_write_iter+0xba2/0x1470 fs/btrfs/file.c:1668
          call_write_iter include/linux/fs.h:2160 [inline]
          do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735
          do_iter_write+0x182/0x700 fs/read_write.c:861
          vfs_iter_write+0x74/0xa0 fs/read_write.c:902
          iter_file_splice_write+0x745/0xc90 fs/splice.c:686
          do_splice_from fs/splice.c:764 [inline]
          direct_splice_actor+0x114/0x180 fs/splice.c:931
          splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886
          do_splice_direct+0x1ab/0x280 fs/splice.c:974
          do_sendfile+0xb19/0x1270 fs/read_write.c:1255
          __do_sys_sendfile64 fs/read_write.c:1323 [inline]
          __se_sys_sendfile64 fs/read_write.c:1309 [inline]
          __x64_sys_sendfile64+0x259/0x2c0 fs/read_write.c:1309
          do_syscall_x64 arch/x86/entry/common.c:50 [inline]
          do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
          entry_SYSCALL_64_after_hwframe+0x63/0xcd

   -> #1 (btrfs-tree-00){++++}-{3:3}:
          __lock_release kernel/locking/lockdep.c:5382 [inline]
          lock_release+0x371/0x810 kernel/locking/lockdep.c:5688
          up_write+0x2a/0x520 kernel/locking/rwsem.c:1614
          btrfs_tree_unlock_rw fs/btrfs/locking.h:189 [inline]
          btrfs_unlock_up_safe+0x1e3/0x290 fs/btrfs/locking.c:238
          search_leaf fs/btrfs/ctree.c:1832 [inline]
          btrfs_search_slot+0x265e/0x2c70 fs/btrfs/ctree.c:2074
          btrfs_insert_empty_items+0xbd/0x1c0 fs/btrfs/ctree.c:4133
          btrfs_insert_delayed_item+0x826/0xfa0 fs/btrfs/delayed-inode.c:746
          btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:824 [inline]
          __btrfs_commit_inode_delayed_items fs/btrfs/delayed-inode.c:1111 [inline]
          __btrfs_run_delayed_items+0x280/0x590 fs/btrfs/delayed-inode.c:1153
          flush_space+0x147/0xe90 fs/btrfs/space-info.c:728
          btrfs_async_reclaim_metadata_space+0x541/0xc10 fs/btrfs/space-info.c:1086
          process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
          worker_thread+0x669/0x1090 kernel/workqueue.c:2436
          kthread+0x2e8/0x3a0 kernel/kthread.c:376
          ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

   -> #0 (&delayed_node->mutex){+.+.}-{3:3}:
          check_prev_add kernel/locking/lockdep.c:3097 [inline]
          check_prevs_add kernel/locking/lockdep.c:3216 [inline]
          validate_chain kernel/locking/lockdep.c:3831 [inline]
          __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055
          lock_acquire kernel/locking/lockdep.c:5668 [inline]
          lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633
          __mutex_lock_common kernel/locking/mutex.c:603 [inline]
          __mutex_lock+0x12f/0x1360 kernel/locking/mutex.c:747
          __btrfs_release_delayed_node.part.0+0xa1/0xf30 fs/btrfs/delayed-inode.c:256
          __btrfs_release_delayed_node fs/btrfs/delayed-inode.c:251 [inline]
          btrfs_release_delayed_node fs/btrfs/delayed-inode.c:281 [inline]
          btrfs_remove_delayed_node+0x52/0x60 fs/btrfs/delayed-inode.c:1285
          btrfs_evict_inode+0x511/0xf30 fs/btrfs/inode.c:5554
          evict+0x2ed/0x6b0 fs/inode.c:664
          dispose_list+0x117/0x1e0 fs/inode.c:697
          prune_icache_sb+0xeb/0x150 fs/inode.c:896
          super_cache_scan+0x391/0x590 fs/super.c:106
          do_shrink_slab+0x464/0xce0 mm/vmscan.c:843
          shrink_slab_memcg mm/vmscan.c:912 [inline]
          shrink_slab+0x388/0x660 mm/vmscan.c:991
          shrink_node_memcgs mm/vmscan.c:6088 [inline]
          shrink_node+0x93d/0x1f30 mm/vmscan.c:6117
          shrink_zones mm/vmscan.c:6355 [inline]
          do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:6417
          try_to_free_mem_cgroup_pages+0x3a4/0xa70 mm/vmscan.c:6732
          reclaim_high.constprop.0+0x182/0x230 mm/memcontrol.c:2393
          mem_cgroup_handle_over_high+0x190/0x520 mm/memcontrol.c:2578
          try_charge_memcg+0xe0c/0x12f0 mm/memcontrol.c:2816
          try_charge mm/memcontrol.c:2827 [inline]
          charge_memcg+0x90/0x3b0 mm/memcontrol.c:6889
          __mem_cgroup_charge+0x2b/0x90 mm/memcontrol.c:6910
          mem_cgroup_charge include/linux/memcontrol.h:667 [inline]
          __filemap_add_folio+0x615/0xf80 mm/filemap.c:852
          filemap_add_folio+0xaf/0x1e0 mm/filemap.c:934
          __filemap_get_folio+0x389/0xd80 mm/filemap.c:1976
          pagecache_get_page+0x2e/0x280 mm/folio-compat.c:104
          find_or_create_page include/linux/pagemap.h:612 [inline]
          alloc_extent_buffer+0x2b9/0x1580 fs/btrfs/extent_io.c:4588
          btrfs_init_new_buffer fs/btrfs/extent-tree.c:4869 [inline]
          btrfs_alloc_tree_block+0x2e1/0x1320 fs/btrfs/extent-tree.c:4988
          __btrfs_cow_block+0x3b2/0x1420 fs/btrfs/ctree.c:440
          btrfs_cow_block+0x2fa/0x950 fs/btrfs/ctree.c:595
          btrfs_search_slot+0x11b0/0x2c70 fs/btrfs/ctree.c:2038
          btrfs_update_root+0xdb/0x630 fs/btrfs/root-tree.c:137
          update_log_root fs/btrfs/tree-log.c:2841 [inline]
          btrfs_sync_log+0xbfb/0x2870 fs/btrfs/tree-log.c:3064
          btrfs_sync_file+0xdb9/0x13c0 fs/btrfs/file.c:1947
          vfs_fsync_range+0x13e/0x230 fs/sync.c:188
          generic_write_sync include/linux/fs.h:2856 [inline]
          iomap_dio_complete+0x73a/0x920 fs/iomap/direct-io.c:128
          btrfs_direct_write fs/btrfs/file.c:1536 [inline]
          btrfs_do_write_iter+0xba2/0x1470 fs/btrfs/file.c:1668
          call_write_iter include/linux/fs.h:2160 [inline]
          do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735
          do_iter_write+0x182/0x700 fs/read_write.c:861
          vfs_iter_write+0x74/0xa0 fs/read_write.c:902
          iter_file_splice_write+0x745/0xc90 fs/splice.c:686
          do_splice_from fs/splice.c:764 [inline]
          direct_splice_actor+0x114/0x180 fs/splice.c:931
          splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886
          do_splice_direct+0x1ab/0x280 fs/splice.c:974
          do_sendfile+0xb19/0x1270 fs/read_write.c:1255
          __do_sys_sendfile64 fs/read_write.c:1323 [inline]
          __se_sys_sendfile64 fs/read_write.c:1309 [inline]
          __x64_sys_sendfile64+0x259/0x2c0 fs/read_write.c:1309
          do_syscall_x64 arch/x86/entry/common.c:50 [inline]
          do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
          entry_SYSCALL_64_after_hwframe+0x63/0xcd

   other info that might help us debug this:

   Chain exists of:
     &delayed_node->mutex --> btrfs-tree-00 --> btrfs-log-00

   Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(btrfs-log-00);
                                  lock(btrfs-tree-00);
                                  lock(btrfs-log-00);
     lock(&delayed_node->mutex);

Holding a read lock on a leaf from a fs/subvolume tree creates a nasty
lock dependency when we are COWing extent buffers for the log tree and we
have two tasks modifying the log tree, with each one in one of the
following 2 scenarios:

1) Modifying the log tree triggers an extent buffer allocation while
   holding a write lock on a parent extent buffer from the log tree.
   Allocating the pages for an extent buffer, or the extent buffer
   struct, can trigger inode eviction and finally the inode eviction
   will trigger a release/remove of a delayed node, which requires
   taking the delayed node's mutex;

2) Allocating a metadata extent for a log tree can trigger the async
   reclaim thread and make us wait for it to release enough space and
   unblock our reservation ticket. The reclaim thread can start flushing
   delayed items, and that in turn results in the need to lock delayed
   node mutexes and in the need to write lock extent buffers of a
   subvolume tree - all this while holding a write lock on the parent
   extent buffer in the log tree.

So one task in scenario 1) running in parallel with another task in
scenario 2) could lead to a deadlock, one wanting to lock a delayed node
mutex while having a read lock on a leaf from the subvolume, while the
other is holding the delayed node's mutex and wants to write lock the same
subvolume leaf for flushing delayed items.

Fix this by cloning the leaf of the fs/subvolume tree, release/unlock the
fs/subvolume leaf and use the clone leaf instead.

Reported-by: syzbot+9b7c21f486f5e7f8d029@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000ccc93c05edc4d8cf@google.com/
CC: stable@vger.kernel.org # 6.0+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
make_mmu_pages_available() must be called with mmu_lock held for write.
However, if the TDP MMU is used, it will be called with mmu_lock held for
read.
This function does nothing unless shadow pages are used, so there is no
race unless nested TDP is used.
Since nested TDP uses shadow pages, old shadow pages may be zapped by this
function even when the TDP MMU is enabled.
Since shadow pages are never allocated by kvm_tdp_mmu_map(), a race
condition can be avoided by not calling make_mmu_pages_available() if the
TDP MMU is currently in use.

I encountered this when repeatedly starting and stopping nested VM.
It can be artificially caused by allocating a large number of nested TDP
SPTEs.

For example, the following BUG and general protection fault are caused in
the host kernel.

pte_list_remove: 00000000cd54fc10 many->many
------------[ cut here ]------------
kernel BUG at arch/x86/kvm/mmu/mmu.c:963!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:pte_list_remove.cold+0x16/0x48 [kvm]
Call Trace:
 <TASK>
 drop_spte+0xe0/0x180 [kvm]
 mmu_page_zap_pte+0x4f/0x140 [kvm]
 __kvm_mmu_prepare_zap_page+0x62/0x3e0 [kvm]
 kvm_mmu_zap_oldest_mmu_pages+0x7d/0xf0 [kvm]
 direct_page_fault+0x3cb/0x9b0 [kvm]
 kvm_tdp_page_fault+0x2c/0xa0 [kvm]
 kvm_mmu_page_fault+0x207/0x930 [kvm]
 npf_interception+0x47/0xb0 [kvm_amd]
 svm_invoke_exit_handler+0x13c/0x1a0 [kvm_amd]
 svm_handle_exit+0xfc/0x2c0 [kvm_amd]
 kvm_arch_vcpu_ioctl_run+0xa79/0x1780 [kvm]
 kvm_vcpu_ioctl+0x29b/0x6f0 [kvm]
 __x64_sys_ioctl+0x95/0xd0
 do_syscall_64+0x5c/0x90

general protection fault, probably for non-canonical address
0xdead000000000122: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:kvm_mmu_commit_zap_page.part.0+0x4b/0xe0 [kvm]
Call Trace:
 <TASK>
 kvm_mmu_zap_oldest_mmu_pages+0xae/0xf0 [kvm]
 direct_page_fault+0x3cb/0x9b0 [kvm]
 kvm_tdp_page_fault+0x2c/0xa0 [kvm]
 kvm_mmu_page_fault+0x207/0x930 [kvm]
 npf_interception+0x47/0xb0 [kvm_amd]

CVE: CVE-2022-45869
Fixes: a2855af ("KVM: x86/mmu: Allow parallel page faults for the TDP MMU")
Signed-off-by: Kazuki Takiguchi <takiguchi.kazuki171@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
test_bpf tail call tests end up as:

  test_bpf: #0 Tail call leaf jited:1 85 PASS
  test_bpf: #1 Tail call 2 jited:1 111 PASS
  test_bpf: #2 Tail call 3 jited:1 145 PASS
  test_bpf: #3 Tail call 4 jited:1 170 PASS
  test_bpf: #4 Tail call load/store leaf jited:1 190 PASS
  test_bpf: #5 Tail call load/store jited:1
  BUG: Unable to handle kernel data access on write at 0xf1b4e000
  Faulting instruction address: 0xbe86b710
  Oops: Kernel access of bad area, sig: 11 [#1]
  BE PAGE_SIZE=4K MMU=Hash PowerMac
  Modules linked in: test_bpf(+)
  CPU: 0 PID: 97 Comm: insmod Not tainted 6.1.0-rc4+ #195
  Hardware name: PowerMac3,1 750CL 0x87210 PowerMac
  NIP:  be86b710 LR: be857e88 CTR: be86b704
  REGS: f1b4df20 TRAP: 0300   Not tainted  (6.1.0-rc4+)
  MSR:  00009032 <EE,ME,IR,DR,RI>  CR: 28008242  XER: 00000000
  DAR: f1b4e000 DSISR: 42000000
  GPR00: 00000001 f1b4dfe c11d2280 00000000 00000000 00000000 00000002 00000000
  GPR08: f1b4e000 be86b704 f1b4e000 00000000 00000000 100d816a f2440000 fe73baa8
  GPR16: f2458000 00000000 c1941ae4 f1fe2248 00000045 c0de0000 f2458030 00000000
  GPR24: 000003e8 0000000f f2458000 f1b4dc90 3e584b46 00000000 f24466a0 c1941a00
  NIP [be86b710] 0xbe86b710
  LR [be857e88] __run_one+0xec/0x264 [test_bpf]
  Call Trace:
  [f1b4dfe] [00000002] 0x2 (unreliable)
  Instruction dump:
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  ---[ end trace 0000000000000000 ]---

This is a tentative to write above the stack. The problem is encoutered
with tests added by commit 38608ee ("bpf, tests: Add load store
test case for tail call")

This happens because tail call is done to a BPF prog with a different
stack_depth. At the time being, the stack is kept as is when the caller
tail calls its callee. But at exit, the callee restores the stack based
on its own properties. Therefore here, at each run, r1 is erroneously
increased by 32 - 16 = 16 bytes.

This was done that way in order to pass the tail call count from caller
to callee through the stack. As powerpc32 doesn't have a red zone in
the stack, it was necessary the maintain the stack as is for the tail
call. But it was not anticipated that the BPF frame size could be
different.

Let's take a new approach. Use register r4 to carry the tail call count
during the tail call, and save it into the stack at function entry if
required. This means the input parameter must be in r3, which is more
correct as it is a 32 bits parameter, then tail call better match with
normal BPF function entry, the down side being that we move that input
parameter back and forth between r3 and r4. That can be optimised later.

Doing that also has the advantage of maximising the common parts between
tail calls and a normal function exit.

With the fix, tail call tests are now successfull:

  test_bpf: #0 Tail call leaf jited:1 53 PASS
  test_bpf: #1 Tail call 2 jited:1 115 PASS
  test_bpf: #2 Tail call 3 jited:1 154 PASS
  test_bpf: #3 Tail call 4 jited:1 165 PASS
  test_bpf: #4 Tail call load/store leaf jited:1 101 PASS
  test_bpf: #5 Tail call load/store jited:1 141 PASS
  test_bpf: #6 Tail call error path, max count reached jited:1 994 PASS
  test_bpf: #7 Tail call count preserved across function calls jited:1 140975 PASS
  test_bpf: #8 Tail call error path, NULL target jited:1 110 PASS
  test_bpf: #9 Tail call error path, index out of range jited:1 69 PASS
  test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed]

Suggested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Fixes: 51c66ad ("powerpc/bpf: Implement extended BPF on PPC32")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/757acccb7fbfc78efa42dcf3c974b46678198905.1669278887.git.christophe.leroy@csgroup.eu
akemnade pushed a commit that referenced this pull request Dec 24, 2022
There is an interesting reference bug when -ENOMEM occurs in calling of
io_install_fixed_file(). KASan report like below:

[   14.057131] ==================================================================
[   14.059161] BUG: KASAN: use-after-free in unix_get_socket+0x10/0x90
[   14.060975] Read of size 8 at addr ffff88800b09cf20 by task kworker/u8:2/45
[   14.062684]
[   14.062768] CPU: 2 PID: 45 Comm: kworker/u8:2 Not tainted 6.1.0-rc4 #1
[   14.063099] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[   14.063666] Workqueue: events_unbound io_ring_exit_work
[   14.063936] Call Trace:
[   14.064065]  <TASK>
[   14.064175]  dump_stack_lvl+0x34/0x48
[   14.064360]  print_report+0x172/0x475
[   14.064547]  ? _raw_spin_lock_irq+0x83/0xe0
[   14.064758]  ? __virt_addr_valid+0xef/0x170
[   14.064975]  ? unix_get_socket+0x10/0x90
[   14.065167]  kasan_report+0xad/0x130
[   14.065353]  ? unix_get_socket+0x10/0x90
[   14.065553]  unix_get_socket+0x10/0x90
[   14.065744]  __io_sqe_files_unregister+0x87/0x1e0
[   14.065989]  ? io_rsrc_refs_drop+0x1c/0xd0
[   14.066199]  io_ring_exit_work+0x388/0x6a5
[   14.066410]  ? io_uring_try_cancel_requests+0x5bf/0x5bf
[   14.066674]  ? try_to_wake_up+0xdb/0x910
[   14.066873]  ? virt_to_head_page+0xbe/0xbe
[   14.067080]  ? __schedule+0x574/0xd20
[   14.067273]  ? read_word_at_a_time+0xe/0x20
[   14.067492]  ? strscpy+0xb5/0x190
[   14.067665]  process_one_work+0x423/0x710
[   14.067879]  worker_thread+0x2a2/0x6f0
[   14.068073]  ? process_one_work+0x710/0x710
[   14.068284]  kthread+0x163/0x1a0
[   14.068454]  ? kthread_complete_and_exit+0x20/0x20
[   14.068697]  ret_from_fork+0x22/0x30
[   14.068886]  </TASK>
[   14.069000]
[   14.069088] Allocated by task 289:
[   14.069269]  kasan_save_stack+0x1e/0x40
[   14.069463]  kasan_set_track+0x21/0x30
[   14.069652]  __kasan_slab_alloc+0x58/0x70
[   14.069899]  kmem_cache_alloc+0xc5/0x200
[   14.070100]  __alloc_file+0x20/0x160
[   14.070283]  alloc_empty_file+0x3b/0xc0
[   14.070479]  path_openat+0xc3/0x1770
[   14.070689]  do_filp_open+0x150/0x270
[   14.070888]  do_sys_openat2+0x113/0x270
[   14.071081]  __x64_sys_openat+0xc8/0x140
[   14.071283]  do_syscall_64+0x3b/0x90
[   14.071466]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   14.071791]
[   14.071874] Freed by task 0:
[   14.072027]  kasan_save_stack+0x1e/0x40
[   14.072224]  kasan_set_track+0x21/0x30
[   14.072415]  kasan_save_free_info+0x2a/0x50
[   14.072627]  __kasan_slab_free+0x106/0x190
[   14.072858]  kmem_cache_free+0x98/0x340
[   14.073075]  rcu_core+0x427/0xe50
[   14.073249]  __do_softirq+0x110/0x3cd
[   14.073440]
[   14.073523] Last potentially related work creation:
[   14.073801]  kasan_save_stack+0x1e/0x40
[   14.074017]  __kasan_record_aux_stack+0x97/0xb0
[   14.074264]  call_rcu+0x41/0x550
[   14.074436]  task_work_run+0xf4/0x170
[   14.074619]  exit_to_user_mode_prepare+0x113/0x120
[   14.074858]  syscall_exit_to_user_mode+0x1d/0x40
[   14.075092]  do_syscall_64+0x48/0x90
[   14.075272]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   14.075529]
[   14.075612] Second to last potentially related work creation:
[   14.075900]  kasan_save_stack+0x1e/0x40
[   14.076098]  __kasan_record_aux_stack+0x97/0xb0
[   14.076325]  task_work_add+0x72/0x1b0
[   14.076512]  fput+0x65/0xc0
[   14.076657]  filp_close+0x8e/0xa0
[   14.076825]  __x64_sys_close+0x15/0x50
[   14.077019]  do_syscall_64+0x3b/0x90
[   14.077199]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[   14.077448]
[   14.077530] The buggy address belongs to the object at ffff88800b09cf00
[   14.077530]  which belongs to the cache filp of size 232
[   14.078105] The buggy address is located 32 bytes inside of
[   14.078105]  232-byte region [ffff88800b09cf00, ffff88800b09cfe8)
[   14.078685]
[   14.078771] The buggy address belongs to the physical page:
[   14.079046] page:000000001bd520e7 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88800b09de00 pfn:0xb09c
[   14.079575] head:000000001bd520e7 order:1 compound_mapcount:0 compound_pincount:0
[   14.079946] flags: 0x100000000010200(slab|head|node=0|zone=1)
[   14.080244] raw: 0100000000010200 0000000000000000 dead000000000001 ffff88800493cc80
[   14.080629] raw: ffff88800b09de00 0000000080190018 00000001ffffffff 0000000000000000
[   14.081016] page dumped because: kasan: bad access detected
[   14.081293]
[   14.081376] Memory state around the buggy address:
[   14.081618]  ffff88800b09ce00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   14.081974]  ffff88800b09ce80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
[   14.082336] >ffff88800b09cf00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   14.082690]                                ^
[   14.082909]  ffff88800b09cf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
[   14.083266]  ffff88800b09d000: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
[   14.083622] ==================================================================

The actual tracing of this bug is shown below:

commit 8c71fe7 ("io_uring: ensure fput() called correspondingly
when direct install fails") adds an additional fput() in
io_fixed_fd_install() when io_file_bitmap_get() returns error values. In
that case, the routine will never make it to io_install_fixed_file() due
to an early return.

static int io_fixed_fd_install(...)
{
  if (alloc_slot) {
    ...
    ret = io_file_bitmap_get(ctx);
    if (unlikely(ret < 0)) {
      io_ring_submit_unlock(ctx, issue_flags);
      fput(file);
      return ret;
    }
    ...
  }
  ...
  ret = io_install_fixed_file(req, file, issue_flags, file_slot);
  ...
}

In the above scenario, the reference is okay as io_fixed_fd_install()
ensures the fput() is called when something bad happens, either via
bitmap or via inner io_install_fixed_file().

However, the commit 61c1b44 ("io_uring: fix deadlock on iowq file
slot alloc") breaks the balance because it places fput() into the common
path for both io_file_bitmap_get() and io_install_fixed_file(). Since
io_install_fixed_file() handles the fput() itself, the reference
underflow come across then.

There are some extra commits make the current code into
io_fixed_fd_install() -> __io_fixed_fd_install() ->
io_install_fixed_file()

However, the fact that there is an extra fput() is called if
io_install_fixed_file() calls fput(). Traversing through the code, I
find that the existing two callers to __io_fixed_fd_install():
io_fixed_fd_install() and io_msg_send_fd() have fput() when handling
error return, this patch simply removes the fput() in
io_install_fixed_file() to fix the bug.

Fixes: 61c1b44 ("io_uring: fix deadlock on iowq file slot alloc")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Link: https://lore.kernel.org/r/be4ba4b.5d44.184a0a406a4.Coremail.linma@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
There is an interesting race condition of poll_refs which could result
in a NULL pointer dereference. The crash trace is like:

KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 30781 Comm: syz-executor.2 Not tainted 6.0.0-g493ffd6605b2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:io_poll_remove_entry io_uring/poll.c:154 [inline]
RIP: 0010:io_poll_remove_entries+0x171/0x5b4 io_uring/poll.c:190
Code: ...
RSP: 0018:ffff88810dfefba0 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc900030c4000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 0000000000000008 R08: ffffffff9764d3dd R09: fffffbfff3836781
R10: fffffbfff3836781 R11: 0000000000000000 R12: 1ffff11003422d60
R13: ffff88801a116b04 R14: ffff88801a116ac0 R15: dffffc0000000000
FS:  00007f9c07497700(0000) GS:ffff88811a600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffb5c00ea98 CR3: 0000000105680005 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 io_apoll_task_func+0x3f/0xa0 io_uring/poll.c:299
 handle_tw_list io_uring/io_uring.c:1037 [inline]
 tctx_task_work+0x37e/0x4f0 io_uring/io_uring.c:1090
 task_work_run+0x13a/0x1b0 kernel/task_work.c:177
 get_signal+0x2402/0x25a0 kernel/signal.c:2635
 arch_do_signal_or_restart+0x3b/0x660 arch/x86/kernel/signal.c:869
 exit_to_user_mode_loop kernel/entry/common.c:166 [inline]
 exit_to_user_mode_prepare+0xc2/0x160 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x58/0x160 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The root cause for this is a tiny overlooking in
io_poll_check_events() when cocurrently run with poll cancel routine
io_poll_cancel_req().

The interleaving to trigger use-after-free:

CPU0                                       |  CPU1
                                           |
io_apoll_task_func()                       |  io_poll_cancel_req()
 io_poll_check_events()                    |
  // do while first loop                   |
  v = atomic_read(...)                     |
  // v = poll_refs = 1                     |
  ...                                      |  io_poll_mark_cancelled()
                                           |   atomic_or()
                                           |   // poll_refs =
IO_POLL_CANCEL_FLAG | 1
                                           |
  atomic_sub_return(...)                   |
  // poll_refs = IO_POLL_CANCEL_FLAG       |
  // loop continue                         |
                                           |
                                           |  io_poll_execute()
                                           |   io_poll_get_ownership()
                                           |   // poll_refs =
IO_POLL_CANCEL_FLAG | 1
                                           |   // gets the ownership
  v = atomic_read(...)                     |
  // poll_refs not change                  |
                                           |
  if (v & IO_POLL_CANCEL_FLAG)             |
   return -ECANCELED;                      |
  // io_poll_check_events return           |
  // will go into                          |
  // io_req_complete_failed() free req     |
                                           |
                                           |  io_apoll_task_func()
                                           |  // also go into
io_req_complete_failed()

And the interleaving to trigger the kernel WARNING:

CPU0                                       |  CPU1
                                           |
io_apoll_task_func()                       |  io_poll_cancel_req()
 io_poll_check_events()                    |
  // do while first loop                   |
  v = atomic_read(...)                     |
  // v = poll_refs = 1                     |
  ...                                      |  io_poll_mark_cancelled()
                                           |   atomic_or()
                                           |   // poll_refs =
IO_POLL_CANCEL_FLAG | 1
                                           |
  atomic_sub_return(...)                   |
  // poll_refs = IO_POLL_CANCEL_FLAG       |
  // loop continue                         |
                                           |
  v = atomic_read(...)                     |
  // v = IO_POLL_CANCEL_FLAG               |
                                           |  io_poll_execute()
                                           |   io_poll_get_ownership()
                                           |   // poll_refs =
IO_POLL_CANCEL_FLAG | 1
                                           |   // gets the ownership
                                           |
  WARN_ON_ONCE(!(v & IO_POLL_REF_MASK)))   |
  // v & IO_POLL_REF_MASK = 0 WARN         |
                                           |
                                           |  io_apoll_task_func()
                                           |  // also go into
io_req_complete_failed()

By looking up the source code and communicating with Pavel, the
implementation of this atomic poll refs should continue the loop of
io_poll_check_events() just to avoid somewhere else to grab the
ownership. Therefore, this patch simply adds another AND operation to
make sure the loop will stop if it finds the poll_refs is exactly equal
to IO_POLL_CANCEL_FLAG. Since io_poll_cancel_req() grabs ownership and
will finally make its way to io_req_complete_failed(), the req will
be reclaimed as expected.

Fixes: aa43477 ("io_uring: poll rework")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
[axboe: tweak description and code style]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
I got a null-ptr-deref report as following when doing fault injection test:

BUG: kernel NULL pointer dereference, address: 0000000000000058
Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 PID: 253 Comm: 507-spi-dm9051 Tainted: G    B            N 6.1.0-rc3+
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:klist_put+0x2d/0xd0
Call Trace:
 <TASK>
 klist_remove+0xf1/0x1c0
 device_release_driver_internal+0x23e/0x2d0
 bus_remove_device+0x1bd/0x240
 device_del+0x357/0x770
 phy_device_remove+0x11/0x30
 mdiobus_unregister+0xa5/0x140
 release_nodes+0x6a/0xa0
 devres_release_all+0xf8/0x150
 device_unbind_cleanup+0x19/0xd0

//probe path:
phy_device_register()
  device_add()

phy_connect
  phy_attach_direct() //set device driver
    probe() //it's failed, driver is not bound
    device_bind_driver() // probe failed, it's not called

//remove path:
phy_device_remove()
  device_del()
    device_release_driver_internal()
      __device_release_driver() //dev->drv is not NULL
        klist_remove() <- knode_driver is not added yet, cause null-ptr-deref

In phy_attach_direct(), after setting the 'dev->driver', probe() fails,
device_bind_driver() is not called, so the knode_driver->n_klist is not
set, then it causes null-ptr-deref in __device_release_driver() while
deleting device. Fix this by setting dev->driver to NULL in the error
path in phy_attach_direct().

Fixes: e139345 ("[PATCH] PHY Layer fixup")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Matt reported a splat at msk close time:

    BUG: sleeping function called from invalid context at net/mptcp/protocol.c:2877
    in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 155, name: packetdrill
    preempt_count: 201, expected: 0
    RCU nest depth: 0, expected: 0
    4 locks held by packetdrill/155:
    #0: ffff888001536990 (&sb->s_type->i_mutex_key#6){+.+.}-{3:3}, at: __sock_release (net/socket.c:650)
    #1: ffff88800b498130 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close (net/mptcp/protocol.c:2973)
    #2: ffff88800b49a130 (sk_lock-AF_INET/1){+.+.}-{0:0}, at: __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    #3: ffff88800b49a0b0 (slock-AF_INET){+...}-{2:2}, at: __lock_sock_fast (include/net/sock.h:1820)
    Preemption disabled at:
    0x0
    CPU: 1 PID: 155 Comm: packetdrill Not tainted 6.1.0-rc5 #365
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
    Call Trace:
    <TASK>
    dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
    __might_resched.cold (kernel/sched/core.c:9891)
    __mptcp_destroy_sock (include/linux/kernel.h:110)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_subflow_queue_clean (include/net/sock.h:1777)
    __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    mptcp_destroy_common (net/mptcp/protocol.c:3170)
    mptcp_destroy (include/net/sock.h:1495)
    __mptcp_destroy_sock (net/mptcp/protocol.c:2886)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_close (net/mptcp/protocol.c:2974)
    inet_release (net/ipv4/af_inet.c:432)
    __sock_release (net/socket.c:651)
    sock_close (net/socket.c:1367)
    __fput (fs/file_table.c:320)
    task_work_run (kernel/task_work.c:181 (discriminator 1))
    exit_to_user_mode_prepare (include/linux/resume_user_mode.h:49)
    syscall_exit_to_user_mode (kernel/entry/common.c:130)
    do_syscall_64 (arch/x86/entry/common.c:87)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

We can't call mptcp_close under the 'fast' socket lock variant, replace
it with a sock_lock_nested() as the relevant code is already under the
listening msk socket lock protection.

Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Closes: multipath-tcp/mptcp_net-next#316
Fixes: 30e51b9 ("mptcp: fix unreleased socket in accept queue")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Walking the nvme_ns_head siblings list is protected by the head's srcu
in nvme_ns_head_submit_bio() but not nvme_mpath_revalidate_paths().
Removing namespaces from the list also fails to synchronize the srcu.
Concurrent scan work can therefore cause use-after-frees.

Hold the head's srcu lock in nvme_mpath_revalidate_paths() and
synchronize with the srcu, not the global RCU, in nvme_ns_remove().

Observed the following panic when making NVMe/RDMA connections
with native multipath on the Rocky Linux 8.6 kernel
(it seems the upstream kernel has the same race condition).
Disassembly shows the faulting instruction is cmp 0x50(%rdx),%rcx;
computing capacity != get_capacity(ns->disk).
Address 0x50 is dereferenced because ns->disk is NULL.
The NULL disk appears to be the result of concurrent scan work
freeing the namespace (note the log line in the middle of the panic).

[37314.206036] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
[37314.206036] nvme0n3: detected capacity change from 0 to 11811160064
[37314.299753] PGD 0 P4D 0
[37314.299756] Oops: 0000 [#1] SMP PTI
[37314.299759] CPU: 29 PID: 322046 Comm: kworker/u98:3 Kdump: loaded Tainted: G        W      X --------- -  - 4.18.0-372.32.1.el8test86.x86_64 #1
[37314.299762] Hardware name: Dell Inc. PowerEdge R720/0JP31P, BIOS 2.7.0 05/23/2018
[37314.299763] Workqueue: nvme-wq nvme_scan_work [nvme_core]
[37314.299783] RIP: 0010:nvme_mpath_revalidate_paths+0x26/0xb0 [nvme_core]
[37314.299790] Code: 1f 44 00 00 66 66 66 66 90 55 53 48 8b 5f 50 48 8b 83 c8 c9 00 00 48 8b 13 48 8b 48 50 48 39 d3 74 20 48 8d 42 d0 48 8b 50 20 <48> 3b 4a 50 74 05 f0 80 60 70 ef 48 8b 50 30 48 8d 42 d0 48 39 d3
[37315.058803] RSP: 0018:ffffabe28f913d10 EFLAGS: 00010202
[37315.121316] RAX: ffff927a077da800 RBX: ffff92991dd70000 RCX: 0000000001600000
[37315.206704] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff92991b719800
[37315.292106] RBP: ffff929a6b70c000 R08: 000000010234cd4a R09: c0000000ffff7fff
[37315.377501] R10: 0000000000000001 R11: ffffabe28f913a30 R12: 0000000000000000
[37315.462889] R13: ffff92992716600c R14: ffff929964e6e030 R15: ffff92991dd70000
[37315.548286] FS:  0000000000000000(0000) GS:ffff92b87fb80000(0000) knlGS:0000000000000000
[37315.645111] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[37315.713871] CR2: 0000000000000050 CR3: 0000002208810006 CR4: 00000000000606e0
[37315.799267] Call Trace:
[37315.828515]  nvme_update_ns_info+0x1ac/0x250 [nvme_core]
[37315.892075]  nvme_validate_or_alloc_ns+0x2ff/0xa00 [nvme_core]
[37315.961871]  ? __blk_mq_free_request+0x6b/0x90
[37316.015021]  nvme_scan_work+0x151/0x240 [nvme_core]
[37316.073371]  process_one_work+0x1a7/0x360
[37316.121318]  ? create_worker+0x1a0/0x1a0
[37316.168227]  worker_thread+0x30/0x390
[37316.212024]  ? create_worker+0x1a0/0x1a0
[37316.258939]  kthread+0x10a/0x120
[37316.297557]  ? set_kthread_struct+0x50/0x50
[37316.347590]  ret_from_fork+0x35/0x40
[37316.390360] Modules linked in: nvme_rdma nvme_tcp(X) nvme_fabrics nvme_core netconsole iscsi_tcp libiscsi_tcp dm_queue_length dm_service_time nf_conntrack_netlink br_netfilter bridge stp llc overlay nft_chain_nat ipt_MASQUERADE nf_nat xt_addrtype xt_CT nft_counter xt_state xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_comment xt_multiport nft_compat nf_tables libcrc32c nfnetlink dm_multipath tg3 rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm intel_rapl_msr iTCO_wdt iTCO_vendor_support dcdbas intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel ipmi_ssif kvm irqbypass crct10dif_pclmul crc32_pclmul mlx5_ib ghash_clmulni_intel ib_uverbs rapl intel_cstate intel_uncore ib_core ipmi_si joydev mei_me pcspkr ipmi_devintf mei lpc_ich wmi ipmi_msghandler acpi_power_meter ext4 mbcache jbd2 sd_mod t10_pi sg mgag200 mlx5_core drm_kms_helper syscopyarea
[37316.390419]  sysfillrect ahci sysimgblt fb_sys_fops libahci drm crc32c_intel libata mlxfw pci_hyperv_intf tls i2c_algo_bit psample dm_mirror dm_region_hash dm_log dm_mod fuse [last unloaded: nvme_core]
[37317.645908] CR2: 0000000000000050

Fixes: e7d6580 ("nvme-multipath: revalidate paths during rescan")
Signed-off-by: Caleb Sander <csander@purestorage.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Syzbot reported a null-ptr-deref bug:

 NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP
 frequency < 30 seconds
 general protection fault, probably for non-canonical address
 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
 CPU: 1 PID: 3603 Comm: segctord Not tainted
 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google
 10/11/2022
 RIP: 0010:nilfs_palloc_commit_free_entry+0xe5/0x6b0
 fs/nilfs2/alloc.c:608
 Code: 00 00 00 00 fc ff df 80 3c 02 00 0f 85 cd 05 00 00 48 b8 00 00 00
 00 00 fc ff df 4c 8b 73 08 49 8d 7e 10 48 89 fa 48 c1 ea 03 <80> 3c 02
 00 0f 85 26 05 00 00 49 8b 46 10 be a6 00 00 00 48 c7 c7
 RSP: 0018:ffffc90003dff830 EFLAGS: 00010212
 RAX: dffffc0000000000 RBX: ffff88802594e218 RCX: 000000000000000d
 RDX: 0000000000000002 RSI: 0000000000002000 RDI: 0000000000000010
 RBP: ffff888071880222 R08: 0000000000000005 R09: 000000000000003f
 R10: 000000000000000d R11: 0000000000000000 R12: ffff888071880158
 R13: ffff88802594e220 R14: 0000000000000000 R15: 0000000000000004
 FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000)
 knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fb1c08316a8 CR3: 0000000018560000 CR4: 0000000000350ee0
 Call Trace:
  <TASK>
  nilfs_dat_commit_free fs/nilfs2/dat.c:114 [inline]
  nilfs_dat_commit_end+0x464/0x5f0 fs/nilfs2/dat.c:193
  nilfs_dat_commit_update+0x26/0x40 fs/nilfs2/dat.c:236
  nilfs_btree_commit_update_v+0x87/0x4a0 fs/nilfs2/btree.c:1940
  nilfs_btree_commit_propagate_v fs/nilfs2/btree.c:2016 [inline]
  nilfs_btree_propagate_v fs/nilfs2/btree.c:2046 [inline]
  nilfs_btree_propagate+0xa00/0xd60 fs/nilfs2/btree.c:2088
  nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337
  nilfs_collect_file_data+0x45/0xd0 fs/nilfs2/segment.c:568
  nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1018
  nilfs_segctor_scan_file+0x3f4/0x6f0 fs/nilfs2/segment.c:1067
  nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1197 [inline]
  nilfs_segctor_collect fs/nilfs2/segment.c:1503 [inline]
  nilfs_segctor_do_construct+0x12fc/0x6af0 fs/nilfs2/segment.c:2045
  nilfs_segctor_construct+0x8e3/0xb30 fs/nilfs2/segment.c:2379
  nilfs_segctor_thread_construct fs/nilfs2/segment.c:2487 [inline]
  nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2570
  kthread+0x2e4/0x3a0 kernel/kthread.c:376
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
  </TASK>
 ...

If DAT metadata file is corrupted on disk, there is a case where
req->pr_desc_bh is NULL and blocknr is 0 at nilfs_dat_commit_end() during
a b-tree operation that cascadingly updates ancestor nodes of the b-tree,
because nilfs_dat_commit_alloc() for a lower level block can initialize
the blocknr on the same DAT entry between nilfs_dat_prepare_end() and
nilfs_dat_commit_end().

If this happens, nilfs_dat_commit_end() calls nilfs_dat_commit_free()
without valid buffer heads in req->pr_desc_bh and req->pr_bitmap_bh, and
causes the NULL pointer dereference above in
nilfs_palloc_commit_free_entry() function, which leads to a crash.

Fix this by adding a NULL check on req->pr_desc_bh and req->pr_bitmap_bh
before nilfs_palloc_commit_free_entry() in nilfs_dat_commit_free().

This also calls nilfs_error() in that case to notify that there is a fatal
flaw in the filesystem metadata and prevent further operations.

Link: https://lkml.kernel.org/r/00000000000097c20205ebaea3d6@google.com
Link: https://lkml.kernel.org/r/20221114040441.1649940-1-zhangpeng362@huawei.com
Link: https://lkml.kernel.org/r/20221119120542.17204-1-konishi.ryusuke@gmail.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+ebe05ee8e98f755f61d0@syzkaller.appspotmail.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
When running as a Xen PV guests commit eed9a32 ("mm: x86: add
CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG") can cause a protection violation in
pmdp_test_and_clear_young():

 BUG: unable to handle page fault for address: ffff8880083374d0
 #PF: supervisor write access in kernel mode
 #PF: error_code(0x0003) - permissions violation
 PGD 3026067 P4D 3026067 PUD 3027067 PMD 7fee5067 PTE 8010000008337065
 Oops: 0003 [#1] PREEMPT SMP NOPTI
 CPU: 7 PID: 158 Comm: kswapd0 Not tainted 6.1.0-rc5-20221118-doflr+ #1
 RIP: e030:pmdp_test_and_clear_young+0x25/0x40

This happens because the Xen hypervisor can't emulate direct writes to
page table entries other than PTEs.

This can easily be fixed by introducing arch_has_hw_nonleaf_pmd_young()
similar to arch_has_hw_pte_young() and test that instead of
CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG.

Link: https://lkml.kernel.org/r/20221123064510.16225-1-jgross@suse.com
Fixes: eed9a32 ("mm: x86: add CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Acked-by: Yu Zhao <yuzhao@google.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Acked-by: David Hildenbrand <david@redhat.com>	[core changes]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
Wei Chen reported a NULL deref in sk_user_ns() [0][1], and Paolo diagnosed
the root cause: in unix_diag_get_exact(), the newly allocated skb does not
have sk. [2]

We must get the user_ns from the NETLINK_CB(in_skb).sk and pass it to
sk_diag_fill().

[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000270
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 12bbce067 P4D 12bbce067 PUD 12bc40067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 27942 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221118 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014
RIP: 0010:sk_user_ns include/net/sock.h:920 [inline]
RIP: 0010:sk_diag_dump_uid net/unix/diag.c:119 [inline]
RIP: 0010:sk_diag_fill+0x77d/0x890 net/unix/diag.c:170
Code: 89 ef e8 66 d4 2d fd c7 44 24 40 00 00 00 00 49 8d 7c 24 18 e8
54 d7 2d fd 49 8b 5c 24 18 48 8d bb 70 02 00 00 e8 43 d7 2d fd <48> 8b
9b 70 02 00 00 48 8d 7b 10 e8 33 d7 2d fd 48 8b 5b 10 48 8d
RSP: 0018:ffffc90000d67968 EFLAGS: 00010246
RAX: ffff88812badaa48 RBX: 0000000000000000 RCX: ffffffff840d481d
RDX: 0000000000000465 RSI: 0000000000000000 RDI: 0000000000000270
RBP: ffffc90000d679a8 R08: 0000000000000277 R09: 0000000000000000
R10: 0001ffffffffffff R11: 0001c90000d679a8 R12: ffff88812ac03800
R13: ffff88812c87c400 R14: ffff88812ae42210 R15: ffff888103026940
FS:  00007f08b4e6f700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000270 CR3: 000000012c58b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 unix_diag_get_exact net/unix/diag.c:285 [inline]
 unix_diag_handler_dump+0x3f9/0x500 net/unix/diag.c:317
 __sock_diag_cmd net/core/sock_diag.c:235 [inline]
 sock_diag_rcv_msg+0x237/0x250 net/core/sock_diag.c:266
 netlink_rcv_skb+0x13e/0x250 net/netlink/af_netlink.c:2564
 sock_diag_rcv+0x24/0x40 net/core/sock_diag.c:277
 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
 netlink_unicast+0x5e9/0x6b0 net/netlink/af_netlink.c:1356
 netlink_sendmsg+0x739/0x860 net/netlink/af_netlink.c:1932
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0x38f/0x500 net/socket.c:2476
 ___sys_sendmsg net/socket.c:2530 [inline]
 __sys_sendmsg+0x197/0x230 net/socket.c:2559
 __do_sys_sendmsg net/socket.c:2568 [inline]
 __se_sys_sendmsg net/socket.c:2566 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2566
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x4697f9
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48
89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d
01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f08b4e6ec48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000077bf80 RCX: 00000000004697f9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000004d29e9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000077bf80
R13: 0000000000000000 R14: 000000000077bf80 R15: 00007ffdb36bc6c0
 </TASK>
Modules linked in:
CR2: 0000000000000270

[1]: https://lore.kernel.org/netdev/CAO4mrfdvyjFpokhNsiwZiP-wpdSD0AStcJwfKcKQdAALQ9_2Qw@mail.gmail.com/
[2]: https://lore.kernel.org/netdev/e04315e7c90d9a75613f3993c2baf2d344eef7eb.camel@redhat.com/

Fixes: cae9910 ("net: Add UNIX_DIAG_UID to Netlink UNIX socket diagnostics.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Wei Chen <harperchen1110@gmail.com>
Diagnosed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
The test prog dumps a single AF_UNIX socket's UID with and without
unshare(CLONE_NEWUSER) and checks if it matches the result of getuid().

Without the preceding patch, the test prog is killed by a NULL deref
in sk_diag_dump_uid().

  # ./diag_uid
  TAP version 13
  1..2
  # Starting 2 tests from 3 test cases.
  #  RUN           diag_uid.uid.1 ...
  BUG: kernel NULL pointer dereference, address: 0000000000000270
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 105212067 P4D 105212067 PUD 1051fe067 PMD 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.amzn2022.0.1 04/01/2014
  RIP: 0010:sk_diag_fill (./include/net/sock.h:920 net/unix/diag.c:119 net/unix/diag.c:170)
  ...
  # 1: Test terminated unexpectedly by signal 9
  #          FAIL  diag_uid.uid.1
  not ok 1 diag_uid.uid.1
  #  RUN           diag_uid.uid_unshare.1 ...
  # 1: Test terminated by timeout
  #          FAIL  diag_uid.uid_unshare.1
  not ok 2 diag_uid.uid_unshare.1
  # FAILED: 0 / 2 tests passed.
  # Totals: pass:0 fail:2 xfail:0 xpass:0 skip:0 error:0

With the patch, the test succeeds.

  # ./diag_uid
  TAP version 13
  1..2
  # Starting 2 tests from 3 test cases.
  #  RUN           diag_uid.uid.1 ...
  #            OK  diag_uid.uid.1
  ok 1 diag_uid.uid.1
  #  RUN           diag_uid.uid_unshare.1 ...
  #            OK  diag_uid.uid_unshare.1
  ok 2 diag_uid.uid_unshare.1
  # PASSED: 2 / 2 tests passed.
  # Totals: pass:2 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
If coretemp_add_core() gets an error then pdata->core_data[indx]
is already NULL and has been kfreed. Don't pass that to
sysfs_remove_group() as that will crash in sysfs_remove_group().

[Shortened for readability]
[91854.020159] sysfs: cannot create duplicate filename '/devices/platform/coretemp.0/hwmon/hwmon2/temp20_label'
<cpu offline>
[91855.126115] BUG: kernel NULL pointer dereference, address: 0000000000000188
[91855.165103] #PF: supervisor read access in kernel mode
[91855.194506] #PF: error_code(0x0000) - not-present page
[91855.224445] PGD 0 P4D 0
[91855.238508] Oops: 0000 [#1] PREEMPT SMP PTI
...
[91855.342716] RIP: 0010:sysfs_remove_group+0xc/0x80
...
[91855.796571] Call Trace:
[91855.810524]  coretemp_cpu_offline+0x12b/0x1dd [coretemp]
[91855.841738]  ? coretemp_cpu_online+0x180/0x180 [coretemp]
[91855.871107]  cpuhp_invoke_callback+0x105/0x4b0
[91855.893432]  cpuhp_thread_fun+0x8e/0x150
...

Fix this by checking for NULL first.

Signed-off-by: Phil Auld <pauld@redhat.com>
Cc: linux-hwmon@vger.kernel.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221117162313.3164803-1-pauld@redhat.com
Fixes: 199e0de ("hwmon: (coretemp) Merge pkgtemp with coretemp")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
QAT devices on Intel Sapphire Rapids and Emerald Rapids have a defect in
address translation service (ATS). These devices may inadvertently issue
ATS invalidation completion before posted writes initiated with
translated address that utilized translations matching the invalidation
address range, violating the invalidation completion ordering.

This patch adds an extra device TLB invalidation for the affected devices,
it is needed to ensure no more posted writes with translated address
following the invalidation completion. Therefore, the ordering is
preserved and data-corruption is prevented.

Device TLBs are invalidated under the following six conditions:
1. Device driver does DMA API unmap IOVA
2. Device driver unbind a PASID from a process, sva_unbind_device()
3. PASID is torn down, after PASID cache is flushed. e.g. process
exit_mmap() due to crash
4. Under SVA usage, called by mmu_notifier.invalidate_range() where
VM has to free pages that were unmapped
5. userspace driver unmaps a DMA buffer
6. Cache invalidation in vSVA usage (upcoming)

For #1 and #2, device drivers are responsible for stopping DMA traffic
before unmap/unbind. For #3, iommu driver gets mmu_notifier to
invalidate TLB the same way as normal user unmap which will do an extra
invalidation. The dTLB invalidation after PASID cache flush does not
need an extra invalidation.

Therefore, we only need to deal with #4 and #5 in this patch. #1 is also
covered by this patch due to common code path with #5.

Tested-by: Yuzhang Luo <yuzhang.luo@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Link: https://lore.kernel.org/r/20221130062449.1360063-1-jacob.jun.pan@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
A NAPI is setup for each network sring to poll data to kernel
The sring with source host is destroyed before live migration and
new sring with target host is setup after live migration.
The NAPI for the old sring is not deleted until setup new sring
with target host after migration. With busy_poll/busy_read enabled,
the NAPI can be polled before got deleted when resume VM.

BUG: unable to handle kernel NULL pointer dereference at
0000000000000008
IP: xennet_poll+0xae/0xd20
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
Call Trace:
 finish_task_switch+0x71/0x230
 timerqueue_del+0x1d/0x40
 hrtimer_try_to_cancel+0xb5/0x110
 xennet_alloc_rx_buffers+0x2a0/0x2a0
 napi_busy_loop+0xdb/0x270
 sock_poll+0x87/0x90
 do_sys_poll+0x26f/0x580
 tracing_map_insert+0x1d4/0x2f0
 event_hist_trigger+0x14a/0x260

 finish_task_switch+0x71/0x230
 __schedule+0x256/0x890
 recalc_sigpending+0x1b/0x50
 xen_sched_clock+0x15/0x20
 __rb_reserve_next+0x12d/0x140
 ring_buffer_lock_reserve+0x123/0x3d0
 event_triggers_call+0x87/0xb0
 trace_event_buffer_commit+0x1c4/0x210
 xen_clocksource_get_cycles+0x15/0x20
 ktime_get_ts64+0x51/0xf0
 SyS_ppoll+0x160/0x1a0
 SyS_ppoll+0x160/0x1a0
 do_syscall_64+0x73/0x130
 entry_SYSCALL_64_after_hwframe+0x41/0xa6
...
RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900
CR2: 0000000000000008
---[ end trace f8601785b354351c ]---

xen frontend should remove the NAPIs for the old srings before live
migration as the bond srings are destroyed

There is a tiny window between the srings are set to NULL and
the NAPIs are disabled, It is safe as the NAPI threads are still
frozen at that time

Signed-off-by: Lin Liu <lin.liu@citrix.com>
Fixes: 4ec2411 ([NET]: Do not check netif_running() and carrier state in ->poll())
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
When booting a arm 32-bit kernel with config CONFIG_AHCI_DWC enabled on
a am57xx-evm board. This happens when the clock references are unnamed
in DT, the strcmp() produces a NULL pointer dereference, see the
following oops, NULL pointer dereference:

[    4.673950] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[    4.682098] [00000000] *pgd=00000000
[    4.685699] Internal error: Oops: 5 [#1] SMP ARM
[    4.690338] Modules linked in:
[    4.693420] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc7 #1
[    4.699615] Hardware name: Generic DRA74X (Flattened Device Tree)
[    4.705749] PC is at strcmp+0x0/0x34
[    4.709350] LR is at ahci_platform_find_clk+0x3c/0x5c
[    4.714416] pc : [<c130c494>]    lr : [<c0c230e0>]    psr: 20000013
[    4.720703] sp : f000dda8  ip : 00000001  fp : c29b1840
[    4.725952] r10: 00000020  r9 : c1b23380  r8 : c1b23368
[    4.731201] r7 : c1ab4cc4  r6 : 00000001  r5 : c3c66040  r4 : 00000000
[    4.737762] r3 : 00000080  r2 : 00000080  r1 : c1ab4cc4  r0 : 00000000
[...]
[    4.998870]  strcmp from ahci_platform_find_clk+0x3c/0x5c
[    5.004302]  ahci_platform_find_clk from ahci_dwc_probe+0x1f0/0x54c
[    5.010589]  ahci_dwc_probe from platform_probe+0x64/0xc0
[    5.016021]  platform_probe from really_probe+0xe8/0x41c
[    5.021362]  really_probe from __driver_probe_device+0xa4/0x204
[    5.027313]  __driver_probe_device from driver_probe_device+0x38/0xc8
[    5.033782]  driver_probe_device from __driver_attach+0xb4/0x1ec
[    5.039825]  __driver_attach from bus_for_each_dev+0x78/0xb8
[    5.045532]  bus_for_each_dev from bus_add_driver+0x17c/0x220
[    5.051300]  bus_add_driver from driver_register+0x90/0x124
[    5.056915]  driver_register from do_one_initcall+0x48/0x1e8
[    5.062591]  do_one_initcall from kernel_init_freeable+0x1cc/0x234
[    5.068817]  kernel_init_freeable from kernel_init+0x20/0x13c
[    5.074584]  kernel_init from ret_from_fork+0x14/0x2c
[    5.079681] Exception stack(0xf000dfb0 to 0xf000dff8)
[    5.084747] dfa0:                                     00000000 00000000 00000000 00000000
[    5.092956] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    5.101165] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    5.107818] Code: e5e32001 e3520000 1afffffb e12fff1e (e4d03001)
[    5.114013] ---[ end trace 0000000000000000 ]---

Add an extra check in the if-statement if hpriv-clks[i].id.

Fixes: 6ce73f3 ("ata: libahci_platform: Add function returning a clock-handle by id")
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
The LTP test pty03 is causing a crash in slcan:
  BUG: kernel NULL pointer dereference, address: 0000000000000008
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 0 PID: 348 Comm: kworker/0:3 Not tainted 6.0.8-1-default #1 openSUSE Tumbleweed 9d20364b934f5aab0a9bdf84e8f45cfdfae39dab
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014
  Workqueue:  0x0 (events)
  RIP: 0010:process_one_work (/home/rich/kernel/linux/kernel/workqueue.c:706 /home/rich/kernel/linux/kernel/workqueue.c:2185)
  Code: 49 89 ff 41 56 41 55 41 54 55 53 48 89 f3 48 83 ec 10 48 8b 06 48 8b 6f 48 49 89 c4 45 30 e4 a8 04 b8 00 00 00 00 4c 0f 44 e0 <49> 8b 44 24 08 44 8b a8 00 01 00 00 41 83 e5 20 f6 45 10 04 75 0e
  RSP: 0018:ffffaf7b40f47e98 EFLAGS: 00010046
  RAX: 0000000000000000 RBX: ffff9d644e1b8b48 RCX: ffff9d649e439968
  RDX: 00000000ffff8455 RSI: ffff9d644e1b8b48 RDI: ffff9d64764aa6c0
  RBP: ffff9d649e4335c0 R08: 0000000000000c00 R09: ffff9d64764aa734
  R10: 0000000000000007 R11: 0000000000000001 R12: 0000000000000000
  R13: ffff9d649e4335e8 R14: ffff9d64490da780 R15: ffff9d64764aa6c0
  FS:  0000000000000000(0000) GS:ffff9d649e400000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000008 CR3: 0000000036424000 CR4: 00000000000006f0
  Call Trace:
   <TASK>
  worker_thread (/home/rich/kernel/linux/kernel/workqueue.c:2436)
  kthread (/home/rich/kernel/linux/kernel/kthread.c:376)
  ret_from_fork (/home/rich/kernel/linux/arch/x86/entry/entry_64.S:312)

Apparently, the slcan's tx_work is freed while being scheduled. While
slcan_netdev_close() (netdev side) calls flush_work(&sl->tx_work),
slcan_close() (tty side) does not. So when the netdev is never set UP,
but the tty is stuffed with bytes and forced to wakeup write, the work
is scheduled, but never flushed.

So add an additional flush_work() to slcan_close() to be sure the work
is flushed under all circumstances.

The Fixes commit below moved flush_work() from slcan_close() to
slcan_netdev_close(). What was the rationale behind it? Maybe we can
drop the one in slcan_netdev_close()?

I see the same pattern in can327. So it perhaps needs the very same fix.

Fixes: cfcb446 ("can: slcan: remove legacy infrastructure")
Link: https://bugzilla.suse.com/show_bug.cgi?id=1205597
Reported-by: Richard Palethorpe <richard.palethorpe@suse.com>
Tested-by: Petr Vorel <petr.vorel@suse.com>
Cc: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: linux-can@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Cc: Max Staudt <max@enpas.org>
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reviewed-by: Max Staudt <max@enpas.org>
Link: https://lore.kernel.org/all/20221201073426.17328-1-jirislaby@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
When sending packets between nodes in netns, it calls tipc_lxc_xmit() for
peer node to receive the packets where tipc_sk_mcast_rcv()/tipc_sk_rcv()
might be called, and it's pretty much like in tipc_rcv().

Currently the local 'node rw lock' is held during calling tipc_lxc_xmit()
to protect the peer_net not being freed by another thread. However, when
receiving these packets, tipc_node_add_conn() might be called where the
peer 'node rw lock' is acquired. Then a dead lock warning is triggered by
lockdep detector, although it is not a real dead lock:

    WARNING: possible recursive locking detected
    --------------------------------------------
    conn_server/1086 is trying to acquire lock:
    ffff8880065cb020 (&n->lock#2){++--}-{2:2}, \
                     at: tipc_node_add_conn.cold.76+0xaa/0x211 [tipc]

    but task is already holding lock:
    ffff8880065cd020 (&n->lock#2){++--}-{2:2}, \
                     at: tipc_node_xmit+0x285/0xb30 [tipc]

    other info that might help us debug this:
     Possible unsafe locking scenario:

           CPU0
           ----
      lock(&n->lock#2);
      lock(&n->lock#2);

     *** DEADLOCK ***

     May be due to missing lock nesting notation

    4 locks held by conn_server/1086:
     #0: ffff8880036d1e40 (sk_lock-AF_TIPC){+.+.}-{0:0}, \
                          at: tipc_accept+0x9c0/0x10b0 [tipc]
     #1: ffff8880036d5f80 (sk_lock-AF_TIPC/1){+.+.}-{0:0}, \
                          at: tipc_accept+0x363/0x10b0 [tipc]
     #2: ffff8880065cd020 (&n->lock#2){++--}-{2:2}, \
                          at: tipc_node_xmit+0x285/0xb30 [tipc]
     #3: ffff888012e13370 (slock-AF_TIPC){+...}-{2:2}, \
                          at: tipc_sk_rcv+0x2da/0x1b40 [tipc]

    Call Trace:
     <TASK>
     dump_stack_lvl+0x44/0x5b
     __lock_acquire.cold.77+0x1f2/0x3d7
     lock_acquire+0x1d2/0x610
     _raw_write_lock_bh+0x38/0x80
     tipc_node_add_conn.cold.76+0xaa/0x211 [tipc]
     tipc_sk_finish_conn+0x21e/0x640 [tipc]
     tipc_sk_filter_rcv+0x147b/0x3030 [tipc]
     tipc_sk_rcv+0xbb4/0x1b40 [tipc]
     tipc_lxc_xmit+0x225/0x26b [tipc]
     tipc_node_xmit.cold.82+0x4a/0x102 [tipc]
     __tipc_sendstream+0x879/0xff0 [tipc]
     tipc_accept+0x966/0x10b0 [tipc]
     do_accept+0x37d/0x590

This patch avoids this warning by not holding the 'node rw lock' before
calling tipc_lxc_xmit(). As to protect the 'peer_net', rcu_read_lock()
should be enough, as in cleanup_net() when freeing the netns, it calls
synchronize_rcu() before the free is continued.

Also since tipc_lxc_xmit() is like the RX path in tipc_rcv(), it makes
sense to call it under rcu_read_lock(). Note that the right lock order
must be:

   rcu_read_lock();
   tipc_node_read_lock(n);
   tipc_node_read_unlock(n);
   tipc_lxc_xmit();
   rcu_read_unlock();

instead of:

   tipc_node_read_lock(n);
   rcu_read_lock();
   tipc_node_read_unlock(n);
   tipc_lxc_xmit();
   rcu_read_unlock();

and we have to call tipc_node_read_lock/unlock() twice in
tipc_node_xmit().

Fixes: f73b128 ("tipc: improve throughput between nodes in netns")
Reported-by: Shuang Li <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/5bdd1f8fee9db695cfff4528a48c9b9d0523fb00.1670110641.git.lucien.xin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
If a cookie expires from the LRU and the LRU_DISCARD flag is set, but
the state machine has not run yet, it's possible another thread can call
fscache_use_cookie and begin to use it.

When the cookie_worker finally runs, it will see the LRU_DISCARD flag
set, transition the cookie->state to LRU_DISCARDING, which will then
withdraw the cookie.  Once the cookie is withdrawn the object is removed
the below oops will occur because the object associated with the cookie
is now NULL.

Fix the oops by clearing the LRU_DISCARD bit if another thread uses the
cookie before the cookie_worker runs.

  BUG: kernel NULL pointer dereference, address: 0000000000000008
  ...
  CPU: 31 PID: 44773 Comm: kworker/u130:1 Tainted: G     E    6.0.0-5.dneg.x86_64 #1
  Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
  Workqueue: events_unbound netfs_rreq_write_to_cache_work [netfs]
  RIP: 0010:cachefiles_prepare_write+0x28/0x90 [cachefiles]
  ...
  Call Trace:
    netfs_rreq_write_to_cache_work+0x11c/0x320 [netfs]
    process_one_work+0x217/0x3e0
    worker_thread+0x4a/0x3b0
    kthread+0xd6/0x100

Fixes: 12bb21a ("fscache: Implement cookie user counting and resource pinning")
Reported-by: Daire Byrne <daire.byrne@gmail.com>
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Daire Byrne <daire@dneg.com>
Link: https://lore.kernel.org/r/20221117115023.1350181-1-dwysocha@redhat.com/ # v1
Link: https://lore.kernel.org/r/20221117142915.1366990-1-dwysocha@redhat.com/ # v2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
KASAN found that addr was dereferenced after br2dev_event_work was freed.

==================================================================
BUG: KASAN: use-after-free in qeth_l2_br2dev_worker+0x5ba/0x6b0
Read of size 1 at addr 00000000fdcea440 by task kworker/u760:4/540
CPU: 17 PID: 540 Comm: kworker/u760:4 Tainted: G            E      6.1.0-20221128.rc7.git1.5aa3bed4ce83.300.fc36.s390x+kasan #1
Hardware name: IBM 8561 T01 703 (LPAR)
Workqueue: 0.0.8000_event qeth_l2_br2dev_worker
Call Trace:
 [<000000016944d4ce>] dump_stack_lvl+0xc6/0xf8
 [<000000016942cd9c>] print_address_description.constprop.0+0x34/0x2a0
 [<000000016942d118>] print_report+0x110/0x1f8
 [<0000000167a7bd04>] kasan_report+0xfc/0x128
 [<000000016938d79a>] qeth_l2_br2dev_worker+0x5ba/0x6b0
 [<00000001673edd1e>] process_one_work+0x76e/0x1128
 [<00000001673ee85c>] worker_thread+0x184/0x1098
 [<000000016740718a>] kthread+0x26a/0x310
 [<00000001672c606a>] __ret_from_fork+0x8a/0xe8
 [<00000001694711da>] ret_from_fork+0xa/0x40
Allocated by task 108338:
 kasan_save_stack+0x40/0x68
 kasan_set_track+0x36/0x48
 __kasan_kmalloc+0xa0/0xc0
 qeth_l2_switchdev_event+0x25a/0x738
 atomic_notifier_call_chain+0x9c/0xf8
 br_switchdev_fdb_notify+0xf4/0x110
 fdb_notify+0x122/0x180
 fdb_add_entry.constprop.0.isra.0+0x312/0x558
 br_fdb_add+0x59e/0x858
 rtnl_fdb_add+0x58a/0x928
 rtnetlink_rcv_msg+0x5f8/0x8d8
 netlink_rcv_skb+0x1f2/0x408
 netlink_unicast+0x570/0x790
 netlink_sendmsg+0x752/0xbe0
 sock_sendmsg+0xca/0x110
 ____sys_sendmsg+0x510/0x6a8
 ___sys_sendmsg+0x12a/0x180
 __sys_sendmsg+0xe6/0x168
 __do_sys_socketcall+0x3c8/0x468
 do_syscall+0x22c/0x328
 __do_syscall+0x94/0xf0
 system_call+0x82/0xb0
Freed by task 540:
 kasan_save_stack+0x40/0x68
 kasan_set_track+0x36/0x48
 kasan_save_free_info+0x4c/0x68
 ____kasan_slab_free+0x14e/0x1a8
 __kasan_slab_free+0x24/0x30
 __kmem_cache_free+0x168/0x338
 qeth_l2_br2dev_worker+0x154/0x6b0
 process_one_work+0x76e/0x1128
 worker_thread+0x184/0x1098
 kthread+0x26a/0x310
 __ret_from_fork+0x8a/0xe8
 ret_from_fork+0xa/0x40
Last potentially related work creation:
 kasan_save_stack+0x40/0x68
 __kasan_record_aux_stack+0xbe/0xd0
 insert_work+0x56/0x2e8
 __queue_work+0x4ce/0xd10
 queue_work_on+0xf4/0x100
 qeth_l2_switchdev_event+0x520/0x738
 atomic_notifier_call_chain+0x9c/0xf8
 br_switchdev_fdb_notify+0xf4/0x110
 fdb_notify+0x122/0x180
 fdb_add_entry.constprop.0.isra.0+0x312/0x558
 br_fdb_add+0x59e/0x858
 rtnl_fdb_add+0x58a/0x928
 rtnetlink_rcv_msg+0x5f8/0x8d8
 netlink_rcv_skb+0x1f2/0x408
 netlink_unicast+0x570/0x790
 netlink_sendmsg+0x752/0xbe0
 sock_sendmsg+0xca/0x110
 ____sys_sendmsg+0x510/0x6a8
 ___sys_sendmsg+0x12a/0x180
 __sys_sendmsg+0xe6/0x168
 __do_sys_socketcall+0x3c8/0x468
 do_syscall+0x22c/0x328
 __do_syscall+0x94/0xf0
 system_call+0x82/0xb0
Second to last potentially related work creation:
 kasan_save_stack+0x40/0x68
 __kasan_record_aux_stack+0xbe/0xd0
 kvfree_call_rcu+0xb2/0x760
 kernfs_unlink_open_file+0x348/0x430
 kernfs_fop_release+0xc2/0x320
 __fput+0x1ae/0x768
 task_work_run+0x1bc/0x298
 exit_to_user_mode_prepare+0x1a0/0x1a8
 __do_syscall+0x94/0xf0
 system_call+0x82/0xb0
The buggy address belongs to the object at 00000000fdcea400
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 64 bytes inside of
 96-byte region [00000000fdcea400, 00000000fdcea460)
The buggy address belongs to the physical page:
page:000000005a9c26e8 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xfdcea
flags: 0x3ffff00000000200(slab|node=0|zone=1|lastcpupid=0x1ffff)
raw: 3ffff00000000200 0000000000000000 0000000100000122 000000008008cc00
raw: 0000000000000000 0020004100000000 ffffffff00000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
 00000000fdcea300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 00000000fdcea380: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>00000000fdcea400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                                           ^
 00000000fdcea480: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 00000000fdcea500: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================

Fixes: f7936b7 ("s390/qeth: Update MACs of LEARNING_SYNC device")
Reported-by: Thorsten Winkler <twinkler@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Thorsten Winkler <twinkler@linux.ibm.com>
Link: https://lore.kernel.org/r/20221207105304.20494-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
The following program will trigger the BUG_ON that this patch removes,
because the user can munmap() mm->brk:

  #include <sys/syscall.h>
  #include <sys/mman.h>
  #include <assert.h>
  #include <unistd.h>

  static void *brk_now(void)
  {
    return (void *)syscall(SYS_brk, 0);
  }

  static void brk_set(void *b)
  {
    assert(syscall(SYS_brk, b) != -1);
  }

  int main(int argc, char *argv[])
  {
    void *b = brk_now();
    brk_set(b + 4096);
    assert(munmap(b - 4096, 4096 * 2) == 0);
    brk_set(b);
    return 0;
  }

Compile that with musl, since glibc actually uses brk(), and then
execute it, and it'll hit this splat:

  kernel BUG at mm/mmap.c:229!
  invalid opcode: 0000 [#1] PREEMPT SMP
  CPU: 12 PID: 1379 Comm: a.out Tainted: G S   U             6.1.0-rc7+ #419
  RIP: 0010:__do_sys_brk+0x2fc/0x340
  Code: 00 00 4c 89 ef e8 04 d3 fe ff eb 9a be 01 00 00 00 4c 89 ff e8 35 e0 fe ff e9 6e ff ff ff 4d 89 a7 20>
  RSP: 0018:ffff888140bc7eb0 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 00000000007e7000 RCX: ffff8881020fe000
  RDX: ffff8881020fe001 RSI: ffff8881955c9b00 RDI: ffff8881955c9b08
  RBP: 0000000000000000 R08: ffff8881955c9b00 R09: 00007ffc77844000
  R10: 0000000000000000 R11: 0000000000000001 R12: 00000000007e8000
  R13: 00000000007e8000 R14: 00000000007e7000 R15: ffff8881020fe000
  FS:  0000000000604298(0000) GS:ffff88901f700000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000603fe0 CR3: 000000015ba9a005 CR4: 0000000000770ee0
  PKRU: 55555554
  Call Trace:
   <TASK>
   do_syscall_64+0x2b/0x50
   entry_SYSCALL_64_after_hwframe+0x46/0xb0
  RIP: 0033:0x400678
  Code: 10 4c 8d 41 08 4c 89 44 24 10 4c 8b 01 8b 4c 24 08 83 f9 2f 77 0a 4c 8d 4c 24 20 4c 01 c9 eb 05 48 8b>
  RSP: 002b:00007ffc77863890 EFLAGS: 00000212 ORIG_RAX: 000000000000000c
  RAX: ffffffffffffffda RBX: 000000000040031b RCX: 0000000000400678
  RDX: 00000000004006a1 RSI: 00000000007e6000 RDI: 00000000007e7000
  RBP: 00007ffc77863900 R08: 0000000000000000 R09: 00000000007e6000
  R10: 00007ffc77863930 R11: 0000000000000212 R12: 00007ffc77863978
  R13: 00007ffc77863988 R14: 0000000000000000 R15: 0000000000000000
   </TASK>

Instead, just return the old brk value if the original mapping has been
removed.

[akpm@linux-foundation.org: fix changelog, per Liam]
Link: https://lkml.kernel.org/r/20221202162724.2009-1-Jason@zx2c4.com
Fixes: 2e7ce7d ("mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap()")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
We use "unsigned long" to store a PFN in the kernel and phys_addr_t to
store a physical address.

On a 64bit system, both are 64bit wide.  However, on a 32bit system, the
latter might be 64bit wide.  This is, for example, the case on x86 with
PAE: phys_addr_t and PTEs are 64bit wide, while "unsigned long" only spans
32bit.

The current definition of SWP_PFN_BITS without MAX_PHYSMEM_BITS misses
that case, and assumes that the maximum PFN is limited by an 32bit
phys_addr_t.  This implies, that SWP_PFN_BITS will currently only be able
to cover 4 GiB - 1 on any 32bit system with 4k page size, which is wrong.

Let's rely on the number of bits in phys_addr_t instead, but make sure to
not exceed the maximum swap offset, to not make the BUILD_BUG_ON() in
is_pfn_swap_entry() unhappy.  Note that swp_entry_t is effectively an
unsigned long and the maximum swap offset shares that value with the swap
type.

For example, on an 8 GiB x86 PAE system with a kernel config based on
Debian 11.5 (-> CONFIG_FLATMEM=y, CONFIG_X86_PAE=y), we will currently
fail removing migration entries (remove_migration_ptes()), because
mm/page_vma_mapped.c:check_pte() will fail to identify a PFN match as
swp_offset_pfn() wrongly masks off PFN bits.  For example,
split_huge_page_to_list()->...->remap_page() will leave migration entries
in place and continue to unlock the page.

Later, when we stumble over these migration entries (e.g., via
/proc/self/pagemap), pfn_swap_entry_to_page() will BUG_ON() because these
migration entries shouldn't exist anymore and the page was unlocked.

[   33.067591] kernel BUG at include/linux/swapops.h:497!
[   33.067597] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[   33.067602] CPU: 3 PID: 742 Comm: cow Tainted: G            E      6.1.0-rc8+ #16
[   33.067605] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
[   33.067606] EIP: pagemap_pmd_range+0x644/0x650
[   33.067612] Code: 00 00 00 00 66 90 89 ce b9 00 f0 ff ff e9 ff fb ff ff 89 d8 31 db e8 48 c6 52 00 e9 23 fb ff ff e8 61 83 56 00 e9 b6 fe ff ff <0f> 0b bf 00 f0 ff ff e9 38 fa ff ff 3e 8d 74 26 00 55 89 e5 57 31
[   33.067615] EAX: ee394000 EBX: 00000002 ECX: ee394000 EDX: 00000000
[   33.067617] ESI: c1b0ded4 EDI: 00024a00 EBP: c1b0ddb4 ESP: c1b0dd68
[   33.067619] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00010246
[   33.067624] CR0: 80050033 CR2: b7a00000 CR3: 01bbbd20 CR4: 00350ef0
[   33.067625] Call Trace:
[   33.067628]  ? madvise_free_pte_range+0x720/0x720
[   33.067632]  ? smaps_pte_range+0x4b0/0x4b0
[   33.067634]  walk_pgd_range+0x325/0x720
[   33.067637]  ? mt_find+0x1d6/0x3a0
[   33.067641]  ? mt_find+0x1d6/0x3a0
[   33.067643]  __walk_page_range+0x164/0x170
[   33.067646]  walk_page_range+0xf9/0x170
[   33.067648]  ? __kmem_cache_alloc_node+0x2a8/0x340
[   33.067653]  pagemap_read+0x124/0x280
[   33.067658]  ? default_llseek+0x101/0x160
[   33.067662]  ? smaps_account+0x1d0/0x1d0
[   33.067664]  vfs_read+0x90/0x290
[   33.067667]  ? do_madvise.part.0+0x24b/0x390
[   33.067669]  ? debug_smp_processor_id+0x12/0x20
[   33.067673]  ksys_pread64+0x58/0x90
[   33.067675]  __ia32_sys_ia32_pread64+0x1b/0x20
[   33.067680]  __do_fast_syscall_32+0x4c/0xc0
[   33.067683]  do_fast_syscall_32+0x29/0x60
[   33.067686]  do_SYSENTER_32+0x15/0x20
[   33.067689]  entry_SYSENTER_32+0x98/0xf1

Decrease the indentation level of SWP_PFN_BITS and SWP_PFN_MASK to keep it
readable and consistent.

[david@redhat.com: rely on sizeof(phys_addr_t) and min_t() instead]
  Link: https://lkml.kernel.org/r/20221206105737.69478-1-david@redhat.com
[david@redhat.com: use "int" for comparison, as we're only comparing numbers < 64]
  Link: https://lkml.kernel.org/r/1f157500-2676-7cef-a84e-9224ed64e540@redhat.com
Link: https://lkml.kernel.org/r/20221205150857.167583-1-david@redhat.com
Fixes: 0d206b5 ("mm/swap: add swp_offset_pfn() to fetch PFN from swap entry")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
akemnade pushed a commit that referenced this pull request Dec 24, 2022
For dax pud, pud_huge() returns true on x86. So the function works as long
as hugetlb is configured. However, dax doesn't depend on hugetlb.
Commit 414fd08 ("mm/gup: fix gup_pmd_range() for dax") fixed
devmap-backed huge PMDs, but missed devmap-backed huge PUDs. Fix this as
well.

This fixes the below kernel panic:

general protection fault, probably for non-canonical address 0x69e7c000cc478: 0000 [#1] SMP
	< snip >
Call Trace:
<TASK>
get_user_pages_fast+0x1f/0x40
iov_iter_get_pages+0xc6/0x3b0
? mempool_alloc+0x5d/0x170
bio_iov_iter_get_pages+0x82/0x4e0
? bvec_alloc+0x91/0xc0
? bio_alloc_bioset+0x19a/0x2a0
blkdev_direct_IO+0x282/0x480
? __io_complete_rw_common+0xc0/0xc0
? filemap_range_has_page+0x82/0xc0
generic_file_direct_write+0x9d/0x1a0
? inode_update_time+0x24/0x30
__generic_file_write_iter+0xbd/0x1e0
blkdev_write_iter+0xb4/0x150
? io_import_iovec+0x8d/0x340
io_write+0xf9/0x300
io_issue_sqe+0x3c3/0x1d30
? sysvec_reschedule_ipi+0x6c/0x80
__io_queue_sqe+0x33/0x240
? fget+0x76/0xa0
io_submit_sqes+0xe6a/0x18d0
? __fget_light+0xd1/0x100
__x64_sys_io_uring_enter+0x199/0x880
? __context_tracking_enter+0x1f/0x70
? irqentry_exit_to_user_mode+0x24/0x30
? irqentry_exit+0x1d/0x30
? __context_tracking_exit+0xe/0x70
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fc97c11a7be
	< snip >
</TASK>
---[ end trace 48b2e0e67debcaeb ]---
RIP: 0010:internal_get_user_pages_fast+0x340/0x990
	< snip >
Kernel panic - not syncing: Fatal exception
Kernel Offset: disabled

Link: https://lkml.kernel.org/r/1670392853-28252-1-git-send-email-ssengar@linux.microsoft.com
Fixes: 414fd08 ("mm/gup: fix gup_pmd_range() for dax")
Signed-off-by: John Starks <jostarks@microsoft.com>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
akemnade pushed a commit that referenced this pull request May 7, 2023
Older platforms and Virtual platforms which doesn't have support for
bluetooth device in ACPI firmware will not have valid ACPI handle.
Check for validity of handle before accessing.

dmesg log from simics environment (virtual platform):

BUG: unable to handle kernel NULL pointer dereference at
0000000000000018
IP: acpi_ns_walk_namespace+0x5c/0x278
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
Modules linked in: bnep intel_powerclamp coretemp kvm_intel
kvm irqbypass intel_cstate input_leds joydev serio_raw mac_hid
btusb(OE) btintel(OE) bluetooth(OE) lpc_ich compat(OE) ecdh_generic
i7core_edac i5500_temp shpchp binfmt_misc sch_fq_codel parport_pc ppdev
lp parport ip_tables x_tables autofs4 hid_generic usbhid hid e1000e
psmouse ahci pata_acpi libahci ptp pps_core floppy
CPU: 0 PID: 35 Comm: kworker/u3:0 Tainted: G           OE
4.15.0-140-generic #144-Ubuntu
Hardware name: Simics Simics, BIOS Simics 01/01/2011
Workqueue: hci0 hci_power_on [bluetooth]
RIP: 0010:acpi_ns_walk_namespace+0x5c/0x278
RSP: 0000:ffffaa9c0049bba8 EFLAGS: 00010246
RAX: 0000000000000001 RBX: 0000000000001001 RCX: 0000000000000010
RDX: ffffffff92ea7e27 RSI: ffffffff92ea7e10 RDI: 00000000000000c8
RBP: ffffaa9c0049bbf8 R08: 0000000000000000 R09: ffffffffc05b39d0
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000000 R14: ffffffffc05b39d0 R15: ffffaa9c0049bc70
FS:  0000000000000000(0000) GS:ffff8be73fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000018 CR3: 0000000075f0e000 CR4: 00000000000006f0

Fixes: 294d749 ("Bluetooth: btintel: Iterate only bluetooth device ACPI entries")
Signed-off-by: Kiran K <kiran.k@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
akemnade pushed a commit that referenced this pull request May 7, 2023
In xfs_buffered_write_iomap_begin, @icur is the iext cursor for the data
fork and @CCur is the cursor for the cow fork.  Pass in whichever cursor
corresponds to allocfork, because otherwise the xfs_iext_prev_extent
call can use the data fork cursor to walk off the end of the cow fork
structure.  Best case it returns the wrong results, worst case it does
this:

stack segment: 0000 [#1] PREEMPT SMP
CPU: 2 PID: 3141909 Comm: fsstress Tainted: G        W          6.3.0-rc2-xfsx #6.3.0-rc2 7bf5cc2e98997627cae5c930d890aba3aeec65dd
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20171121_152543-x86-ol7-builder-01.us.oracle.com-4.el7.1 04/01/2014
RIP: 0010:xfs_iext_prev+0x71/0x150 [xfs]
RSP: 0018:ffffc90002233aa8 EFLAGS: 00010297
RAX: 000000000000000f RBX: 000000000000000e RCX: 000000000000000c
RDX: 0000000000000002 RSI: 000000000000000e RDI: ffff8883d0019ba0
RBP: 989642409af8a7a7 R08: ffffea0000000001 R09: 0000000000000002
R10: 0000000000000000 R11: 000000000000000c R12: ffffc90002233b00
R13: ffff8883d0019ba0 R14: 989642409af8a6bf R15: 000ffffffffe0000
FS:  00007fdf8115f740(0000) GS:ffff88843fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf8115e000 CR3: 0000000357256000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 xfs_iomap_prealloc_size.constprop.0.isra.0+0x1a6/0x410 [xfs 619a268fb2406d68bd34e007a816b27e70abc22c]
 xfs_buffered_write_iomap_begin+0xa87/0xc60 [xfs 619a268fb2406d68bd34e007a816b27e70abc22c]
 iomap_iter+0x132/0x2f0
 iomap_file_buffered_write+0x92/0x330
 xfs_file_buffered_write+0xb1/0x330 [xfs 619a268fb2406d68bd34e007a816b27e70abc22c]
 vfs_write+0x2eb/0x410
 ksys_write+0x65/0xe0
 do_syscall_64+0x2b/0x80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Found by xfs/538 in alwayscow mode, but this doesn't seem particular to
that test.

Fixes: 590b165 ("xfs: refactor xfs_iomap_prealloc_size")
Actually-Fixes: 66ae56a ("xfs: introduce an always_cow mode")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
akemnade pushed a commit that referenced this pull request May 7, 2023
The failover txq is inited as 16 queues.
when a packet is transmitted from the failover device firstly,
the failover device will select the queue which is returned from
the primary device if the primary device is UP and running.
If the primary device txq is bigger than the default 16,
it can lead to the following warning:
eth0 selects TX queue 18, but real number of TX queues is 16

The warning backtrace is:
[   32.146376] CPU: 18 PID: 9134 Comm: chronyd Tainted: G            E      6.2.8-1.el7.centos.x86_64 #1
[   32.147175] Hardware name: Red Hat KVM, BIOS 1.10.2-3.el7_4.1 04/01/2014
[   32.147730] Call Trace:
[   32.147971]  <TASK>
[   32.148183]  dump_stack_lvl+0x48/0x70
[   32.148514]  dump_stack+0x10/0x20
[   32.148820]  netdev_core_pick_tx+0xb1/0xe0
[   32.149180]  __dev_queue_xmit+0x529/0xcf0
[   32.149533]  ? __check_object_size.part.0+0x21c/0x2c0
[   32.149967]  ip_finish_output2+0x278/0x560
[   32.150327]  __ip_finish_output+0x1fe/0x2f0
[   32.150690]  ip_finish_output+0x2a/0xd0
[   32.151032]  ip_output+0x7a/0x110
[   32.151337]  ? __pfx_ip_finish_output+0x10/0x10
[   32.151733]  ip_local_out+0x5e/0x70
[   32.152054]  ip_send_skb+0x19/0x50
[   32.152366]  udp_send_skb.isra.0+0x163/0x3a0
[   32.152736]  udp_sendmsg+0xba8/0xec0
[   32.153060]  ? __folio_memcg_unlock+0x25/0x60
[   32.153445]  ? __pfx_ip_generic_getfrag+0x10/0x10
[   32.153854]  ? sock_has_perm+0x85/0xa0
[   32.154190]  inet_sendmsg+0x6d/0x80
[   32.154508]  ? inet_sendmsg+0x6d/0x80
[   32.154838]  sock_sendmsg+0x62/0x70
[   32.155152]  ____sys_sendmsg+0x134/0x290
[   32.155499]  ___sys_sendmsg+0x81/0xc0
[   32.155828]  ? _get_random_bytes.part.0+0x79/0x1a0
[   32.156240]  ? ip4_datagram_release_cb+0x5f/0x1e0
[   32.156649]  ? get_random_u16+0x69/0xf0
[   32.156989]  ? __fget_light+0xcf/0x110
[   32.157326]  __sys_sendmmsg+0xc4/0x210
[   32.157657]  ? __sys_connect+0xb7/0xe0
[   32.157995]  ? __audit_syscall_entry+0xce/0x140
[   32.158388]  ? syscall_trace_enter.isra.0+0x12c/0x1a0
[   32.158820]  __x64_sys_sendmmsg+0x24/0x30
[   32.159171]  do_syscall_64+0x38/0x90
[   32.159493]  entry_SYSCALL_64_after_hwframe+0x72/0xdc

Fix that by reducing txq number as the non-existent primary-dev does.

Fixes: cfc80d9 ("net: Introduce net_failover driver")
Signed-off-by: Faicker Mo <faicker.mo@ucloud.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
akemnade pushed a commit that referenced this pull request May 7, 2023
… into HEAD

KVM/riscv fixes for 6.3, take #1

- Fix VM hang in case of timer delta being zero
akemnade pushed a commit that referenced this pull request May 7, 2023
…scrub

Before relocating a block group we pause scrub, then do the relocation and
then unpause scrub. The relocation process requires starting and committing
a transaction, and if we have a failure in the critical section of the
transaction commit path (transaction state >= TRANS_STATE_COMMIT_START),
we will deadlock if there is a paused scrub.

That results in stack traces like the following:

  [42.479] BTRFS info (device sdc): relocating block group 53876686848 flags metadata|raid6
  [42.936] BTRFS warning (device sdc): Skipping commit of aborted transaction.
  [42.936] ------------[ cut here ]------------
  [42.936] BTRFS: Transaction aborted (error -28)
  [42.936] WARNING: CPU: 11 PID: 346822 at fs/btrfs/transaction.c:1977 btrfs_commit_transaction+0xcc8/0xeb0 [btrfs]
  [42.936] Modules linked in: dm_flakey dm_mod loop btrfs (...)
  [42.936] CPU: 11 PID: 346822 Comm: btrfs Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [42.936] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [42.936] RIP: 0010:btrfs_commit_transaction+0xcc8/0xeb0 [btrfs]
  [42.936] Code: ff ff 45 8b (...)
  [42.936] RSP: 0018:ffffb58649633b48 EFLAGS: 00010282
  [42.936] RAX: 0000000000000000 RBX: ffff8be6ef4d5bd8 RCX: 0000000000000000
  [42.936] RDX: 0000000000000002 RSI: ffffffffb35e7782 RDI: 00000000ffffffff
  [42.936] RBP: ffff8be6ef4d5c98 R08: 0000000000000000 R09: ffffb586496339e8
  [42.936] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8be6d38c7c00
  [42.936] R13: 00000000ffffffe4 R14: ffff8be6c268c000 R15: ffff8be6ef4d5cf0
  [42.936] FS:  00007f381a82b340(0000) GS:ffff8beddfcc0000(0000) knlGS:0000000000000000
  [42.936] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [42.936] CR2: 00007f1e35fb7638 CR3: 0000000117680006 CR4: 0000000000370ee0
  [42.936] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [42.936] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [42.936] Call Trace:
  [42.936]  <TASK>
  [42.936]  ? start_transaction+0xcb/0x610 [btrfs]
  [42.936]  prepare_to_relocate+0x111/0x1a0 [btrfs]
  [42.936]  relocate_block_group+0x57/0x5d0 [btrfs]
  [42.936]  ? btrfs_wait_nocow_writers+0x25/0xb0 [btrfs]
  [42.936]  btrfs_relocate_block_group+0x248/0x3c0 [btrfs]
  [42.936]  ? __pfx_autoremove_wake_function+0x10/0x10
  [42.936]  btrfs_relocate_chunk+0x3b/0x150 [btrfs]
  [42.936]  btrfs_balance+0x8ff/0x11d0 [btrfs]
  [42.936]  ? __kmem_cache_alloc_node+0x14a/0x410
  [42.936]  btrfs_ioctl+0x2334/0x32c0 [btrfs]
  [42.937]  ? mod_objcg_state+0xd2/0x360
  [42.937]  ? refill_obj_stock+0xb0/0x160
  [42.937]  ? seq_release+0x25/0x30
  [42.937]  ? __rseq_handle_notify_resume+0x3b5/0x4b0
  [42.937]  ? percpu_counter_add_batch+0x2e/0xa0
  [42.937]  ? __x64_sys_ioctl+0x88/0xc0
  [42.937]  __x64_sys_ioctl+0x88/0xc0
  [42.937]  do_syscall_64+0x38/0x90
  [42.937]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [42.937] RIP: 0033:0x7f381a6ffe9b
  [42.937] Code: 00 48 89 44 24 (...)
  [42.937] RSP: 002b:00007ffd45ecf060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [42.937] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f381a6ffe9b
  [42.937] RDX: 00007ffd45ecf150 RSI: 00000000c4009420 RDI: 0000000000000003
  [42.937] RBP: 0000000000000003 R08: 0000000000000013 R09: 0000000000000000
  [42.937] R10: 00007f381a60c878 R11: 0000000000000246 R12: 00007ffd45ed0423
  [42.937] R13: 00007ffd45ecf150 R14: 0000000000000000 R15: 00007ffd45ecf148
  [42.937]  </TASK>
  [42.937] ---[ end trace 0000000000000000 ]---
  [42.937] BTRFS: error (device sdc: state A) in cleanup_transaction:1977: errno=-28 No space left
  [59.196] INFO: task btrfs:346772 blocked for more than 120 seconds.
  [59.196]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.196] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.196] task:btrfs           state:D stack:0     pid:346772 ppid:1      flags:0x00004002
  [59.196] Call Trace:
  [59.196]  <TASK>
  [59.196]  __schedule+0x392/0xa70
  [59.196]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.196]  schedule+0x5d/0xd0
  [59.196]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.197]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.197]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.197]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.197]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.198]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.198]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.198]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.198]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.198]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.198]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.199]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.199]  ? _copy_from_user+0x7b/0x80
  [59.199]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.199]  ? refill_stock+0x33/0x50
  [59.199]  ? should_failslab+0xa/0x20
  [59.199]  ? kmem_cache_alloc_node+0x151/0x460
  [59.199]  ? alloc_io_context+0x1b/0x80
  [59.199]  ? preempt_count_add+0x70/0xa0
  [59.199]  ? __x64_sys_ioctl+0x88/0xc0
  [59.199]  __x64_sys_ioctl+0x88/0xc0
  [59.199]  do_syscall_64+0x38/0x90
  [59.199]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.199] RIP: 0033:0x7f82ffaffe9b
  [59.199] RSP: 002b:00007f82ff9fcc50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.199] RAX: ffffffffffffffda RBX: 000055b191e36310 RCX: 00007f82ffaffe9b
  [59.199] RDX: 000055b191e36310 RSI: 00000000c400941b RDI: 0000000000000003
  [59.199] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.199] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82ff9fd640
  [59.199] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.199]  </TASK>
  [59.199] INFO: task btrfs:346773 blocked for more than 120 seconds.
  [59.200]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.200] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.201] task:btrfs           state:D stack:0     pid:346773 ppid:1      flags:0x00004002
  [59.201] Call Trace:
  [59.201]  <TASK>
  [59.201]  __schedule+0x392/0xa70
  [59.201]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.201]  schedule+0x5d/0xd0
  [59.201]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.201]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.201]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.202]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.202]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.202]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.202]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.202]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.203]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.203]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.203]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.203]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.203]  ? _copy_from_user+0x7b/0x80
  [59.203]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.204]  ? should_failslab+0xa/0x20
  [59.204]  ? kmem_cache_alloc_node+0x151/0x460
  [59.204]  ? alloc_io_context+0x1b/0x80
  [59.204]  ? preempt_count_add+0x70/0xa0
  [59.204]  ? __x64_sys_ioctl+0x88/0xc0
  [59.204]  __x64_sys_ioctl+0x88/0xc0
  [59.204]  do_syscall_64+0x38/0x90
  [59.204]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.204] RIP: 0033:0x7f82ffaffe9b
  [59.204] RSP: 002b:00007f82ff1fbc50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.204] RAX: ffffffffffffffda RBX: 000055b191e36790 RCX: 00007f82ffaffe9b
  [59.204] RDX: 000055b191e36790 RSI: 00000000c400941b RDI: 0000000000000003
  [59.204] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.204] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82ff1fc640
  [59.204] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.204]  </TASK>
  [59.204] INFO: task btrfs:346774 blocked for more than 120 seconds.
  [59.205]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.205] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.206] task:btrfs           state:D stack:0     pid:346774 ppid:1      flags:0x00004002
  [59.206] Call Trace:
  [59.206]  <TASK>
  [59.206]  __schedule+0x392/0xa70
  [59.206]  schedule+0x5d/0xd0
  [59.206]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.206]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.206]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.207]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.207]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.207]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.207]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.208]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.208]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.208]  ? __mutex_unlock_slowpath.isra.0+0x9a/0x120
  [59.208]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.208]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.209]  ? _copy_from_user+0x7b/0x80
  [59.209]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.209]  ? should_failslab+0xa/0x20
  [59.209]  ? kmem_cache_alloc_node+0x151/0x460
  [59.209]  ? alloc_io_context+0x1b/0x80
  [59.209]  ? preempt_count_add+0x70/0xa0
  [59.209]  ? __x64_sys_ioctl+0x88/0xc0
  [59.209]  __x64_sys_ioctl+0x88/0xc0
  [59.209]  do_syscall_64+0x38/0x90
  [59.209]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.209] RIP: 0033:0x7f82ffaffe9b
  [59.209] RSP: 002b:00007f82fe9fac50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.209] RAX: ffffffffffffffda RBX: 000055b191e36c10 RCX: 00007f82ffaffe9b
  [59.209] RDX: 000055b191e36c10 RSI: 00000000c400941b RDI: 0000000000000003
  [59.209] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.209] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fe9fb640
  [59.209] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.209]  </TASK>
  [59.209] INFO: task btrfs:346775 blocked for more than 120 seconds.
  [59.210]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.210] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.211] task:btrfs           state:D stack:0     pid:346775 ppid:1      flags:0x00004002
  [59.211] Call Trace:
  [59.211]  <TASK>
  [59.211]  __schedule+0x392/0xa70
  [59.211]  schedule+0x5d/0xd0
  [59.211]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.211]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.211]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.212]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.212]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.212]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.212]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.213]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.213]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.213]  ? __mutex_unlock_slowpath.isra.0+0x9a/0x120
  [59.213]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.213]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.214]  ? _copy_from_user+0x7b/0x80
  [59.214]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.214]  ? should_failslab+0xa/0x20
  [59.214]  ? kmem_cache_alloc_node+0x151/0x460
  [59.214]  ? alloc_io_context+0x1b/0x80
  [59.214]  ? preempt_count_add+0x70/0xa0
  [59.214]  ? __x64_sys_ioctl+0x88/0xc0
  [59.214]  __x64_sys_ioctl+0x88/0xc0
  [59.214]  do_syscall_64+0x38/0x90
  [59.214]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.214] RIP: 0033:0x7f82ffaffe9b
  [59.214] RSP: 002b:00007f82fe1f9c50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.214] RAX: ffffffffffffffda RBX: 000055b191e37090 RCX: 00007f82ffaffe9b
  [59.214] RDX: 000055b191e37090 RSI: 00000000c400941b RDI: 0000000000000003
  [59.214] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.214] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fe1fa640
  [59.214] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.214]  </TASK>
  [59.214] INFO: task btrfs:346776 blocked for more than 120 seconds.
  [59.215]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.216] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.217] task:btrfs           state:D stack:0     pid:346776 ppid:1      flags:0x00004002
  [59.217] Call Trace:
  [59.217]  <TASK>
  [59.217]  __schedule+0x392/0xa70
  [59.217]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.217]  schedule+0x5d/0xd0
  [59.217]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.217]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.217]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.217]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.217]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.218]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.218]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.218]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.218]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.219]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.219]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.219]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.219]  ? _copy_from_user+0x7b/0x80
  [59.219]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.219]  ? should_failslab+0xa/0x20
  [59.219]  ? kmem_cache_alloc_node+0x151/0x460
  [59.219]  ? alloc_io_context+0x1b/0x80
  [59.219]  ? preempt_count_add+0x70/0xa0
  [59.219]  ? __x64_sys_ioctl+0x88/0xc0
  [59.219]  __x64_sys_ioctl+0x88/0xc0
  [59.219]  do_syscall_64+0x38/0x90
  [59.219]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.219] RIP: 0033:0x7f82ffaffe9b
  [59.219] RSP: 002b:00007f82fd9f8c50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.219] RAX: ffffffffffffffda RBX: 000055b191e37510 RCX: 00007f82ffaffe9b
  [59.219] RDX: 000055b191e37510 RSI: 00000000c400941b RDI: 0000000000000003
  [59.219] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.219] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fd9f9640
  [59.219] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.219]  </TASK>
  [59.219] INFO: task btrfs:346822 blocked for more than 120 seconds.
  [59.220]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.221] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.222] task:btrfs           state:D stack:0     pid:346822 ppid:1      flags:0x00004002
  [59.222] Call Trace:
  [59.222]  <TASK>
  [59.222]  __schedule+0x392/0xa70
  [59.222]  schedule+0x5d/0xd0
  [59.222]  btrfs_scrub_cancel+0x91/0x100 [btrfs]
  [59.222]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.222]  btrfs_commit_transaction+0x572/0xeb0 [btrfs]
  [59.223]  ? start_transaction+0xcb/0x610 [btrfs]
  [59.223]  prepare_to_relocate+0x111/0x1a0 [btrfs]
  [59.223]  relocate_block_group+0x57/0x5d0 [btrfs]
  [59.223]  ? btrfs_wait_nocow_writers+0x25/0xb0 [btrfs]
  [59.223]  btrfs_relocate_block_group+0x248/0x3c0 [btrfs]
  [59.224]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.224]  btrfs_relocate_chunk+0x3b/0x150 [btrfs]
  [59.224]  btrfs_balance+0x8ff/0x11d0 [btrfs]
  [59.224]  ? __kmem_cache_alloc_node+0x14a/0x410
  [59.224]  btrfs_ioctl+0x2334/0x32c0 [btrfs]
  [59.225]  ? mod_objcg_state+0xd2/0x360
  [59.225]  ? refill_obj_stock+0xb0/0x160
  [59.225]  ? seq_release+0x25/0x30
  [59.225]  ? __rseq_handle_notify_resume+0x3b5/0x4b0
  [59.225]  ? percpu_counter_add_batch+0x2e/0xa0
  [59.225]  ? __x64_sys_ioctl+0x88/0xc0
  [59.225]  __x64_sys_ioctl+0x88/0xc0
  [59.225]  do_syscall_64+0x38/0x90
  [59.225]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.225] RIP: 0033:0x7f381a6ffe9b
  [59.225] RSP: 002b:00007ffd45ecf060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.225] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f381a6ffe9b
  [59.225] RDX: 00007ffd45ecf150 RSI: 00000000c4009420 RDI: 0000000000000003
  [59.225] RBP: 0000000000000003 R08: 0000000000000013 R09: 0000000000000000
  [59.225] R10: 00007f381a60c878 R11: 0000000000000246 R12: 00007ffd45ed0423
  [59.225] R13: 00007ffd45ecf150 R14: 0000000000000000 R15: 00007ffd45ecf148
  [59.225]  </TASK>

What happens is the following:

1) A scrub is running, so fs_info->scrubs_running is 1;

2) Task A starts block group relocation, and at btrfs_relocate_chunk() it
   pauses scrub by calling btrfs_scrub_pause(). That increments
   fs_info->scrub_pause_req from 0 to 1 and waits for the scrub task to
   pause (for fs_info->scrubs_paused to be == to fs_info->scrubs_running);

3) The scrub task pauses at scrub_pause_off(), waiting for
   fs_info->scrub_pause_req to decrease to 0;

4) Task A then enters btrfs_relocate_block_group(), and down that call
   chain we start a transaction and then attempt to commit it;

5) When task A calls btrfs_commit_transaction(), it either will do the
   commit itself or wait for some other task that already started the
   commit of the transaction - it doesn't matter which case;

6) The transaction commit enters state TRANS_STATE_COMMIT_START;

7) An error happens during the transaction commit, like -ENOSPC when
   running delayed refs or delayed items for example;

8) This results in calling transaction.c:cleanup_transaction(), where
   we call btrfs_scrub_cancel(), incrementing fs_info->scrub_cancel_req
   from 0 to 1, and blocking this task waiting for fs_info->scrubs_running
   to decrease to 0;

9) From this point on, both the transaction commit and the scrub task
   hang forever:

   1) The transaction commit is waiting for fs_info->scrubs_running to
      be decreased to 0;

   2) The scrub task is at scrub_pause_off() waiting for
      fs_info->scrub_pause_req to decrease to 0 - so it can not proceed
      to stop the scrub and decrement fs_info->scrubs_running from 0 to 1.

   Therefore resulting in a deadlock.

Fix this by having cleanup_transaction(), called if a transaction commit
fails, not call btrfs_scrub_cancel() if relocation is in progress, and
having btrfs_relocate_block_group() call btrfs_scrub_cancel() instead if
the relocation failed and a transaction abort happened.

This was triggered with btrfs/061 from fstests.

Fixes: 55e3a60 ("btrfs: Fix data checksum error cause by replace with io-load.")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
akemnade pushed a commit that referenced this pull request May 7, 2023
powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which
from my (arguably very short) checking is not commonly done for other
archs. This is fine, except when PF_IO_WORKER's have been created and
the task does something that causes a coredump to be generated. Then we
get this crash:

  Kernel attempted to read user page (160) - exploit attempt? (uid: 1000)
  BUG: Kernel NULL pointer dereference on read at 0x00000160
  Faulting instruction address: 0xc0000000000c3a60
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries
  Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod
  CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88
  Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
  NIP:  c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0
  REGS: c0000000041833b0 TRAP: 0300   Not tainted  (6.3.0-rc2+)
  MSR:  800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 88082828  XER: 200400f8
  ...
  NIP memcpy_power7+0x200/0x7d0
  LR  ppr_get+0x64/0xb0
  Call Trace:
    ppr_get+0x40/0xb0 (unreliable)
    __regset_get+0x180/0x1f0
    regset_get_alloc+0x64/0x90
    elf_core_dump+0xb98/0x1b60
    do_coredump+0x1c34/0x24a0
    get_signal+0x71c/0x1410
    do_notify_resume+0x140/0x6f0
    interrupt_exit_user_prepare_main+0x29c/0x320
    interrupt_exit_user_prepare+0x6c/0xa0
    interrupt_return_srr_user+0x8/0x138

Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL
pt_regs.

Check for a valid pt_regs in both ppc_get/ppr_set, and return an error
if not set. The actual error value doesn't seem to be important here, so
just pick -EINVAL.

Fixes: fa43981 ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[mpe: Trim oops in change log, add Fixes & Cc stable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk
akemnade pushed a commit that referenced this pull request May 7, 2023
snd_card_ymfpci_remove() was removed in commit c6e6bb5 ("ALSA:
ymfpci: Allocate resources with device-managed APIs"), but the call to
snd_card_new() was not replaced with snd_devm_card_new().

Since there was no longer a call to snd_card_free, unloading the module
would eventually result in Oops:

[697561.532887] BUG: unable to handle page fault for address: ffffffffc0924480
[697561.532893] #PF: supervisor read access in kernel mode
[697561.532896] #PF: error_code(0x0000) - not-present page
[697561.532899] PGD ae1e15067 P4D ae1e15067 PUD ae1e17067 PMD 11a8f5067 PTE 0
[697561.532905] Oops: 0000 [#1] PREEMPT SMP NOPTI
[697561.532909] CPU: 21 PID: 5080 Comm: wireplumber Tainted: G        W  OE      6.2.7 #1
[697561.532914] Hardware name: System manufacturer System Product Name/TUF GAMING X570-PLUS, BIOS 4408 10/28/2022
[697561.532916] RIP: 0010:try_module_get.part.0+0x1a/0xe0
[697561.532924] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 49 89 fc bf 01 00 00 00 e8 56 3c f8 ff <41> 83 3c 24 02 0f 84 96 00 00 00 41 8b 84 24 30 03 00 00 85 c0 0f
[697561.532927] RSP: 0018:ffffbe9b858c3bd8 EFLAGS: 00010246
[697561.532930] RAX: ffff9815d14f1900 RBX: ffff9815c14e6000 RCX: 0000000000000000
[697561.532933] RDX: 0000000000000000 RSI: ffffffffc055092c RDI: ffffffffb3778c1a
[697561.532935] RBP: ffffbe9b858c3be8 R08: 0000000000000040 R09: ffff981a1a741380
[697561.532937] R10: ffffbe9b858c3c80 R11: 00000009d56533a6 R12: ffffffffc0924480
[697561.532939] R13: ffff9823439d8500 R14: 0000000000000025 R15: ffff9815cd109f80
[697561.532942] FS:  00007f13084f1f80(0000) GS:ffff9824aef40000(0000) knlGS:0000000000000000
[697561.532945] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[697561.532947] CR2: ffffffffc0924480 CR3: 0000000145344000 CR4: 0000000000350ee0
[697561.532949] Call Trace:
[697561.532951]  <TASK>
[697561.532955]  try_module_get+0x13/0x30
[697561.532960]  snd_ctl_open+0x61/0x1c0 [snd]
[697561.532976]  snd_open+0xb4/0x1e0 [snd]
[697561.532989]  chrdev_open+0xc7/0x240
[697561.532995]  ? fsnotify_perm.part.0+0x6e/0x160
[697561.533000]  ? __pfx_chrdev_open+0x10/0x10
[697561.533005]  do_dentry_open+0x169/0x440
[697561.533009]  vfs_open+0x2d/0x40
[697561.533012]  path_openat+0xa9d/0x10d0
[697561.533017]  ? debug_smp_processor_id+0x17/0x20
[697561.533022]  ? trigger_load_balance+0x65/0x370
[697561.533026]  do_filp_open+0xb2/0x160
[697561.533032]  ? _raw_spin_unlock+0x19/0x40
[697561.533036]  ? alloc_fd+0xa9/0x190
[697561.533040]  do_sys_openat2+0x9f/0x160
[697561.533044]  __x64_sys_openat+0x55/0x90
[697561.533048]  do_syscall_64+0x3b/0x90
[697561.533052]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
[697561.533056] RIP: 0033:0x7f1308a40db4
[697561.533059] Code: 24 20 eb 8f 66 90 44 89 54 24 0c e8 46 68 f8 ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 32 44 89 c7 89 44 24 0c e8 78 68 f8 ff 8b 44
[697561.533062] RSP: 002b:00007ffcce664450 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
[697561.533066] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1308a40db4
[697561.533068] RDX: 0000000000080000 RSI: 00007ffcce664690 RDI: 00000000ffffff9c
[697561.533070] RBP: 00007ffcce664690 R08: 0000000000000000 R09: 0000000000000012
[697561.533072] R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000080000
[697561.533074] R13: 00007f13054b069b R14: 0000565209f83200 R15: 0000000000000000
[697561.533078]  </TASK>

Fixes: c6e6bb5 ("ALSA: ymfpci: Allocate resources with device-managed APIs")
Signed-off-by: Tasos Sahanidis <tasos@tasossah.com>
Link: https://lore.kernel.org/r/20230329032422.170024-1-tasos@tasossah.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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