syzbot


possible deadlock in ocfs2_page_mkwrite

Status: upstream: reported C repro on 2024/09/12 09:35
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+2e6495950edcf7fbfccf@syzkaller.appspotmail.com
First crash: 152d, last: 1h21m
Cause bisection: introduced by (bisect log) :
commit a3c06ae158dd6fa8336157c31d9234689d068d02
Author: Parav Pandit <parav@nvidia.com>
Date: Tue Jan 5 10:32:03 2021 +0000

  vdpa_sim_net: Add support for user supported devices

Crash: possible deadlock in ocfs2_get_system_file_inode (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] possible deadlock in ocfs2_page_mkwrite 0 (3) 2024/11/17 17:49
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in ocfs2_page_mkwrite 6 15d 98d 0/3 upstream: reported on 2024/11/04 07:05
linux-5.15 possible deadlock in ocfs2_page_mkwrite 5 34d 147d 0/3 upstream: reported on 2024/09/16 20:58

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc7-syzkaller-00192-gb5a24181e461 #0 Not tainted
------------------------------------------------------
syz-executor420/5970 is trying to acquire lock:
ffff88807839b120 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142

but task is already holding lock:
ffff88807c820518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (sb_pagefaults){.+.+}-{0:0}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1716 [inline]
       sb_start_pagefault include/linux/fs.h:1881 [inline]
       ocfs2_page_mkwrite+0x222/0xed0 fs/ocfs2/mmap.c:122
       do_page_mkwrite+0x198/0x480 mm/memory.c:3162
       do_shared_fault mm/memory.c:5373 [inline]
       do_fault mm/memory.c:5435 [inline]
       do_pte_missing mm/memory.c:3965 [inline]
       handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766
       __handle_mm_fault mm/memory.c:5909 [inline]
       handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077
       do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

-> #1 (&mm->mmap_lock){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       __might_fault+0xc6/0x120 mm/memory.c:6716
       _inline_copy_to_user include/linux/uaccess.h:192 [inline]
       _copy_to_user+0x2c/0xb0 lib/usercopy.c:26
       copy_to_user include/linux/uaccess.h:225 [inline]
       fiemap_fill_next_extent+0x235/0x410 fs/ioctl.c:145
       ocfs2_fiemap_inline fs/ocfs2/extent_map.c:725 [inline]
       ocfs2_fiemap+0xc25/0xf80 fs/ocfs2/extent_map.c:762
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
       __do_sys_ioctl fs/ioctl.c:905 [inline]
       __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
       __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       down_write+0x99/0x220 kernel/locking/rwsem.c:1577
       ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142
       do_page_mkwrite+0x198/0x480 mm/memory.c:3162
       do_shared_fault mm/memory.c:5373 [inline]
       do_fault mm/memory.c:5435 [inline]
       do_pte_missing mm/memory.c:3965 [inline]
       handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766
       __handle_mm_fault mm/memory.c:5909 [inline]
       handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077
       do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

Chain exists of:
  &ocfs2_file_ip_alloc_sem_key --> &mm->mmap_lock --> sb_pagefaults

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(sb_pagefaults);
                               lock(&mm->mmap_lock);
                               lock(sb_pagefaults);
  lock(&ocfs2_file_ip_alloc_sem_key);

 *** DEADLOCK ***

2 locks held by syz-executor420/5970:
 #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline]
 #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6114 [inline]
 #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6174
 #1: ffff88807c820518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162

stack backtrace:
CPU: 1 UID: 0 PID: 5970 Comm: syz-executor420 Not tainted 6.12.0-rc7-syzkaller-00192-gb5a24181e461 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 down_write+0x99/0x220 kernel/locking/rwsem.c:1577
 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142
 do_page_mkwrite+0x198/0x480 mm/memory.c:3162
 do_shared_fault mm/memory.c:5373 [inline]
 do_fault mm/memory.c:5435 [inline]
 do_pte_missing mm/memory.c:3965 [inline]
 handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766
 __handle_mm_fault mm/memory.c:5909 [inline]
 handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f47ff734108
Code: 48 8b 35 23 50 0b 00 ba 01 cf 20 00 31 c0 bf 4d 00 00 00 e8 5a 46 03 00 66 0f 6f 05 f2 66 08 00 48 b8 2e 2f 66 69 6c 65 31 00 <c7> 04 25 c0 01 00 20 74 72 65 65 48 89 04 25 00 00 00 20 ba 03 00
RSP: 002b:00007ffdcacffc30 EFLAGS: 00010217
RAX: 0031656c69662f2e RBX: 696c6e695f78616d RCX: 00007f47ff768769
RDX: 00007f47ff768769 RSI: 000000000020cf01 RDI: 0000000000000006
RBP: 6569727261626f6e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffdcacffc5c
R13: 000000000000002d R14: 431bde82d7b634db R15: 00007ffdcacffc90
 </TASK>

Crashes (565):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/17 01:24 upstream b5a24181e461 cfe3a04a .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/11 05:41 upstream febbc555cf0f 43f51a00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/10 20:37 upstream a64dcfb451e2 43f51a00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/09 01:06 upstream 8f6629c004b1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/08 20:22 upstream 8f6629c004b1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/07 05:15 upstream bb066fe812d6 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/07 03:46 upstream bb066fe812d6 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/06 21:48 upstream 92514ef226f5 8002dd28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/06 16:23 upstream 92514ef226f5 577d049b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/06 14:05 upstream 92514ef226f5 577d049b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_page_mkwrite
2025/02/05 19:12 upstream 5c8c229261f1 4dc70884 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/05 13:00 upstream 5c8c229261f1 5896748e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/05 11:40 upstream 5c8c229261f1 5896748e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/04 23:30 upstream d009de7d5428 4baca3d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_page_mkwrite
2025/02/04 11:47 upstream 0de63bb7d919 8f267cef .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/04 10:24 upstream 0de63bb7d919 8f267cef .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/04 06:10 upstream 0de63bb7d919 8f267cef .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/03 19:48 upstream 2014c95afece a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/02/02 08:59 upstream 69e858e0b8b2 568559e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root possible deadlock in ocfs2_page_mkwrite
2025/01/31 19:12 upstream 69b8923f5003 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/31 11:38 upstream 69e858e0b8b2 4c6ac32f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/22 17:02 upstream c4b9570cfb63 a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/22 15:36 upstream c4b9570cfb63 a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/22 15:35 upstream c4b9570cfb63 a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/22 11:55 upstream c4b9570cfb63 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/22 04:17 upstream b9d8a295ed6b da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/21 11:17 upstream 95ec54a420b8 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/21 04:18 upstream 100ceb4817a2 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/21 02:43 upstream 100ceb4817a2 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/20 09:01 upstream ffd294d346d1 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/19 21:25 upstream 9528d418de4d f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/19 13:05 upstream fda5e3f28400 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/19 02:39 upstream fda5e3f28400 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/18 19:28 upstream 595523945be0 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_page_mkwrite
2025/01/18 05:52 upstream 9bffa1ad25b8 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in ocfs2_page_mkwrite
2025/02/07 09:52 upstream bb066fe812d6 53657d1b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_page_mkwrite
2025/01/27 04:43 upstream c2da8b3f914f 9fbd772e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_page_mkwrite
2024/09/11 11:59 upstream 8d8d276ba2fb 8ab55d0e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root possible deadlock in ocfs2_page_mkwrite
2025/02/10 06:40 linux-next df5d6180169a ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in ocfs2_page_mkwrite
2025/02/04 03:32 linux-next 00f3246adeea a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in ocfs2_page_mkwrite
2025/02/08 17:02 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2014c95afece ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/02/06 10:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2014c95afece 577d049b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/02/04 07:25 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 8f267cef .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/02/03 13:44 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/02/01 21:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 0dff8567 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/30 22:50 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 9c8ab845 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/28 07:57 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/28 01:20 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/25 08:27 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/22 23:57 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 25e17fd3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/21 16:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
2025/01/20 12:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in ocfs2_page_mkwrite
* Struck through repros no longer work on HEAD.