syzbot


possible deadlock in ocfs2_xattr_set

Status: upstream: reported on 2024/09/25 09:02
Reported-by: syzbot+c0d46b51c54922dc038f@syzkaller.appspotmail.com
First crash: 471d, last: 6h59m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in ocfs2_xattr_set 4 436 9h36m 482d 0/3 upstream: reported on 2024/09/14 01:11
upstream possible deadlock in ocfs2_xattr_set ocfs2 4 7249 17m 486d 0/29 upstream: reported on 2024/09/10 05:07
linux-6.6 possible deadlock in ocfs2_xattr_set 4 306 23h41m 204d 0/2 upstream: reported on 2025/06/19 18:15

Sample crash report:
ocfs2: Mounting device (7,2) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.72/4585 is trying to acquire lock:
ffff8880560d3488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880560d3488 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: ocfs2_xattr_set+0xad6/0x11e0 fs/ocfs2/xattr.c:3626

but task is already holding lock:
ffff8880560d3ff8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x40c/0x11e0 fs/ocfs2/xattr.c:3587

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&oi->ip_xattr_sem){++++}-{3:3}:
       down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
       ocfs2_init_acl+0x2fb/0x720 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x1463/0x2350 fs/ocfs2/namei.c:410
       ocfs2_create+0x1b6/0x4a0 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x1187/0x2e70 fs/namei.c:3788
       do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
       do_sys_openat2+0x142/0x490 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_openat fs/open.c:1352 [inline]
       __se_sys_openat fs/open.c:1347 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1347
       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

-> #1 (jbd2_handle){++++}-{0:0}:
       jbd2_journal_lock_updates+0xa7/0x380 fs/jbd2/transaction.c:880
       __ocfs2_flush_truncate_log+0x2cd/0x11d0 fs/ocfs2/alloc.c:6030
       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:1191
       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+0xee/0x180 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

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{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_xattr_set+0xad6/0x11e0 fs/ocfs2/xattr.c:3626
       __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
       __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x168/0x2f0 fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x2b2/0x2d0 fs/xattr.c:617
       path_setxattr+0x142/0x280 fs/xattr.c:636
       __do_sys_lsetxattr fs/xattr.c:659 [inline]
       __se_sys_lsetxattr fs/xattr.c:655 [inline]
       __x64_sys_lsetxattr+0xb4/0xd0 fs/xattr.c:655
       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

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8 --> jbd2_handle --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(jbd2_handle);
                               lock(&oi->ip_xattr_sem);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8);

 *** DEADLOCK ***

3 locks held by syz.2.72/4585:
 #0: ffff8880784b4460 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff8880560d42c8 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff8880560d42c8 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: vfs_setxattr+0x141/0x2f0 fs/xattr.c:308
 #2: ffff8880560d3ff8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x40c/0x11e0 fs/ocfs2/xattr.c:3587

stack backtrace:
CPU: 0 PID: 4585 Comm: syz.2.72 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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_xattr_set+0xad6/0x11e0 fs/ocfs2/xattr.c:3626
 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x168/0x2f0 fs/xattr.c:309
 do_setxattr fs/xattr.c:594 [inline]
 setxattr+0x2b2/0x2d0 fs/xattr.c:617
 path_setxattr+0x142/0x280 fs/xattr.c:636
 __do_sys_lsetxattr fs/xattr.c:659 [inline]
 __se_sys_lsetxattr fs/xattr.c:655 [inline]
 __x64_sys_lsetxattr+0xb4/0xd0 fs/xattr.c:655
 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
RIP: 0033:0x7fccdc58f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fccdd47e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007fccdc7e5fa0 RCX: 00007fccdc58f749
RDX: 0000200000000000 RSI: 0000200000000380 RDI: 00002000000002c0
RBP: 00007fccdc613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fccdc7e6038 R14: 00007fccdc7e5fa0 R15: 00007ffc644cebb8
 </TASK>
(syz.2.72,4585,0):ocfs2_dio_end_io:2428 ERROR: Direct IO failed, bytes = -5

Crashes (672):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/30 04:31 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2025/12/27 09:59 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2025/12/26 20:31 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2024/09/25 09:02 linux-6.1.y e526b12bf916 349a68c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/09 17:25 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/09 13:02 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/09 09:39 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/09 04:51 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/08 20:11 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/08 14:36 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/08 10:27 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/08 09:22 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/06 07:50 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/06 05:18 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/06 01:24 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/06 00:22 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/05 10:16 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/05 08:41 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/05 05:21 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/04 19:38 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/04 10:26 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/04 07:38 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/03 05:07 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/02 21:41 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/01 21:41 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/01 16:30 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/01 14:50 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/01 07:27 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/01 06:22 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/31 18:31 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/31 14:18 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/31 04:02 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/30 23:21 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/30 08:47 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/30 06:47 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/28 18:41 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/28 06:29 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/27 23:02 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/27 17:48 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/27 11:59 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/27 01:32 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/26 22:04 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/26 19:11 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/26 18:05 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2025/12/26 11:17 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
* Struck through repros no longer work on HEAD.