syzbot


possible deadlock in __ocfs2_flush_truncate_log

Status: upstream: reported on 2025/03/14 12:11
Reported-by: syzbot+8ee11b9169d68fdff162@syzkaller.appspotmail.com
First crash: 111d, last: 21h11m
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in __ocfs2_flush_truncate_log ocfs2 C inconclusive 2280 2h47m 110d 0/29 upstream: reported C repro on 2025/03/15 11:28
linux-6.6 possible deadlock in __ocfs2_flush_truncate_log origin:upstream C 38 3h13m 7d02h 0/2 upstream: reported C repro on 2025/06/27 02:38
linux-5.15 possible deadlock in __ocfs2_flush_truncate_log 474 22h26m 111d 0/3 upstream: reported on 2025/03/14 17:58

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.1.141-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor/4253 is trying to acquire lock:
ffff8880707f5f48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880707f5f48 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: __ocfs2_flush_truncate_log+0x34f/0x11d0 fs/ocfs2/alloc.c:6047

but task is already holding lock:
ffff888055509808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff888055509808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_flush_truncate_log+0x43/0x60 fs/ocfs2/alloc.c:6076

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
       __ocfs2_move_extents_range+0x1a61/0x3360 fs/ocfs2/move_extents.c:860
       ocfs2_move_extents+0x37c/0x960 fs/ocfs2/move_extents.c:927
       ocfs2_ioctl_move_extents+0x4da/0x6b0 fs/ocfs2/move_extents.c:1053
       ocfs2_ioctl+0x2d7/0x740 fs/ocfs2/ioctl.c:930
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
       lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       __ocfs2_flush_truncate_log+0x34f/0x11d0 fs/ocfs2/alloc.c:6047
       ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6077
       ocfs2_sync_fs+0x113/0x310 fs/ocfs2/super.c:402
       sync_filesystem+0x1be/0x220 fs/sync.c:66
       generic_shutdown_super+0x6b/0x340 fs/super.c:474
       kill_block_super+0x7c/0xe0 fs/super.c:1470
       deactivate_locked_super+0x93/0xf0 fs/super.c:332
       cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182
       task_work_run+0x1ca/0x250 kernel/task_work.c:203
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
       __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
       syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
       do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);

 *** DEADLOCK ***

2 locks held by syz-executor/4253:
 #0: ffff88802fce60e0 (&type->s_umount_key#50){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
 #1: ffff888055509808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888055509808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_flush_truncate_log+0x43/0x60 fs/ocfs2/alloc.c:6076

stack backtrace:
CPU: 0 PID: 4253 Comm: syz-executor Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 __ocfs2_flush_truncate_log+0x34f/0x11d0 fs/ocfs2/alloc.c:6047
 ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6077
 ocfs2_sync_fs+0x113/0x310 fs/ocfs2/super.c:402
 sync_filesystem+0x1be/0x220 fs/sync.c:66
 generic_shutdown_super+0x6b/0x340 fs/super.c:474
 kill_block_super+0x7c/0xe0 fs/super.c:1470
 deactivate_locked_super+0x93/0xf0 fs/super.c:332
 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faab458fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc48419a68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007faab4610925 RCX: 00007faab458fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc48419b20
RBP: 00007ffc48419b20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc4841abb0
R13: 00007faab4610925 R14: 0000000000011eda R15: 00007ffc4841abf0
 </TASK>
ocfs2: Unmounting device (7,1) on (node local)
EXT4-fs (loop1): unmounting filesystem.

Crashes (588):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/27 05:41 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/26 23:59 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/22 06:59 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/11 01:12 linux-6.1.y 58485ff1a74f 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 19:59 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 19:34 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 19:06 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 12:36 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 12:24 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 12:07 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 11:33 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 07:33 linux-6.1.y 7e69c33e4858 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/02 17:23 linux-6.1.y 7e69c33e4858 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/02 07:37 linux-6.1.y 7e69c33e4858 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/02 07:30 linux-6.1.y 7e69c33e4858 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 18:15 linux-6.1.y 7e69c33e4858 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 04:09 linux-6.1.y 7e69c33e4858 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 01:04 linux-6.1.y 7e69c33e4858 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/29 17:10 linux-6.1.y 7e69c33e4858 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/29 17:07 linux-6.1.y 7e69c33e4858 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/27 03:54 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/26 16:36 linux-6.1.y 58485ff1a74f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/26 02:03 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/26 00:39 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/26 00:00 linux-6.1.y 58485ff1a74f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/24 14:03 linux-6.1.y 58485ff1a74f e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/24 09:28 linux-6.1.y 58485ff1a74f e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/24 08:28 linux-6.1.y 58485ff1a74f e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/24 08:23 linux-6.1.y 58485ff1a74f e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/24 01:36 linux-6.1.y 58485ff1a74f e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/23 20:40 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/23 14:58 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/22 15:23 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/21 06:11 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/20 20:50 linux-6.1.y 58485ff1a74f 804b3919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/20 20:39 linux-6.1.y 58485ff1a74f 804b3919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/19 07:08 linux-6.1.y 58485ff1a74f ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/15 21:54 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/15 21:34 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/15 20:16 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/09 04:38 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 20:35 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 15:46 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/08 10:52 linux-6.1.y 58485ff1a74f 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/06/05 00:47 linux-6.1.y 58485ff1a74f 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
2025/03/14 12:10 linux-6.1.y 344a09659766 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in __ocfs2_flush_truncate_log
* Struck through repros no longer work on HEAD.