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: 539d, last: 1h47m
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 4 449 9d10h 551d 0/3 upstream: reported on 2024/09/14 01:11
upstream possible deadlock in ocfs2_xattr_set ocfs2 4 8487 1h10m 555d 0/29 upstream: reported on 2024/09/10 05:07
linux-6.6 possible deadlock in ocfs2_xattr_set 4 389 8d03h 272d 0/2 upstream: reported on 2025/06/19 18:15

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.776/7949 is trying to acquire lock:
ffff888054cced88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff888054cced88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: ocfs2_xattr_set+0xba0/0x13e0 fs/ocfs2/xattr.c:3626

but task is already holding lock:
ffff888054ddce38 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x472/0x13e0 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+0x307/0x770 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x15e8/0x25b0 fs/ocfs2/namei.c:410
       ocfs2_create+0x1b6/0x4b0 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x1181/0x2ee0 fs/namei.c:3788
       do_filp_open+0x1f1/0x430 fs/namei.c:3818
       do_sys_openat2+0x150/0x4b0 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_creat fs/open.c:1414 [inline]
       __se_sys_creat fs/open.c:1408 [inline]
       __x64_sys_creat+0x8c/0xb0 fs/open.c:1408
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (jbd2_handle){++++}-{0:0}:
       jbd2_journal_lock_updates+0xa8/0x390 fs/jbd2/transaction.c:880
       __ocfs2_flush_truncate_log+0x2cf/0x1220 fs/ocfs2/alloc.c:6029
       ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6076
       ocfs2_sync_fs+0x119/0x330 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+0x42c/0x4b0 fs/namespace.c:1191
       task_work_run+0x1d0/0x260 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:82
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{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+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
       lock_acquire+0x1bb/0x4a0 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+0xba0/0x13e0 fs/ocfs2/xattr.c:3626
       __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
       __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x167/0x2e0 fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x346/0x360 fs/xattr.c:617
       path_setxattr+0x147/0x290 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:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       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]#7 --> 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]#7);

 *** DEADLOCK ***

3 locks held by syz.3.776/7949:
 #0: ffff88807cdde460 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff888054ddd108 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888054ddd108 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:308
 #2: ffff888054ddce38 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x472/0x13e0 fs/ocfs2/xattr.c:3587

stack backtrace:
CPU: 1 PID: 7949 Comm: syz.3.776 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x296/0x330 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+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
 lock_acquire+0x1bb/0x4a0 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+0xba0/0x13e0 fs/ocfs2/xattr.c:3626
 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:309
 do_setxattr fs/xattr.c:594 [inline]
 setxattr+0x346/0x360 fs/xattr.c:617
 path_setxattr+0x147/0x290 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:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd0f6b9c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd0f7acd028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007fd0f6e16090 RCX: 00007fd0f6b9c799
RDX: 0000000000000000 RSI: 0000200000000740 RDI: 0000200000000700
RBP: 00007fd0f6c32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd0f6e16128 R14: 00007fd0f6e16090 R15: 00007ffe3c4395c8
 </TASK>

Crashes (766):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/12 01:40 linux-6.1.y f2ddafa93a25 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/03/11 15:52 linux-6.1.y f2ddafa93a25 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/03/10 13:07 linux-6.1.y f2ddafa93a25 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/19 23:12 linux-6.1.y cd9b81672742 572effc1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/19 19:14 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/19 18:14 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/18 13:20 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/17 19:30 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/17 18:14 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/17 01:22 linux-6.1.y bec0e10ee67e 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/01/16 23:40 linux-6.1.y bec0e10ee67e 20d37d28 .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
2026/03/19 05:55 linux-6.1.y f2ddafa93a25 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/16 21:28 linux-6.1.y f2ddafa93a25 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/12 12:49 linux-6.1.y f2ddafa93a25 4efadf07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/11 21:01 linux-6.1.y f2ddafa93a25 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/11 19:05 linux-6.1.y f2ddafa93a25 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/11 04:57 linux-6.1.y f2ddafa93a25 86914af9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/10 03:29 linux-6.1.y f2ddafa93a25 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/09 18:18 linux-6.1.y f2ddafa93a25 176bead5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/09 16:44 linux-6.1.y f2ddafa93a25 176bead5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/07 14:20 linux-6.1.y f2ddafa93a25 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/01 17:48 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/01 02:05 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/03/01 00:33 linux-6.1.y 779f9571ac3e 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/26 18:55 linux-6.1.y 779f9571ac3e ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/24 16:21 linux-6.1.y 779f9571ac3e 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/15 09:08 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/13 04:24 linux-6.1.y 8ce36b2849ef 504cb1bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/11 14:39 linux-6.1.y 0182cb5b74ee 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/11 14:39 linux-6.1.y 0182cb5b74ee 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/09 15:20 linux-6.1.y 0182cb5b74ee df949cd9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/02/07 01:09 linux-6.1.y 0182cb5b74ee f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/31 16:31 linux-6.1.y cd9b81672742 afc0c4d4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/30 00:52 linux-6.1.y cd9b81672742 bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/21 07:48 linux-6.1.y cd9b81672742 6f1aa2f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/21 05:50 linux-6.1.y cd9b81672742 6f1aa2f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/19 14:52 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/19 12:13 linux-6.1.y cd9b81672742 a9fc5226 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/19 03:51 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/17 20:54 linux-6.1.y cd9b81672742 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/17 10:07 linux-6.1.y bec0e10ee67e 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/17 05:18 linux-6.1.y bec0e10ee67e 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/17 02:58 linux-6.1.y bec0e10ee67e 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/16 11:07 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/01/15 19:23 linux-6.1.y bec0e10ee67e 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.