possible deadlock in ocfs2_xattr_get (2)

Status: upstream: reported on 2026/08/27 19:48
Subsystems: ocfs2
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+c63f5bc973ab97368c21@syzkaller.appspotmail.com
First crash: 19d, last: 48m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
af1bb660 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ possible deadlock in ocfs2_xattr_get (2) 2026/08/25 00:39 2026/08/25 00:39 2026/08/25 01:17 23caa175
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] possible deadlock in ocfs2_xattr_get (2) 0 (1) 2026/08/27 19:48
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in ocfs2_xattr_get ocfs2 4 syz, C 655 216d 700d 0/29 auto-obsoleted due to no activity on 2026/07/12 22:30

Sample crash report:
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.129/6766 is trying to acquire lock:
ffff88805fd529d8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578

but task is already holding lock:
ffff88802aa5d118 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&journal->j_trans_barrier){.+.+}-{4:4}:
       down_read+0x97/0x200 kernel/locking/rwsem.c:1574
       ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369
       ocfs2_block_group_alloc fs/ocfs2/suballoc.c:801 [inline]
       ocfs2_reserve_suballoc_bits+0x7b7/0x4850 fs/ocfs2/suballoc.c:950
       ocfs2_reserve_new_metadata_blocks+0x415/0x9a0 fs/ocfs2/suballoc.c:1100
       ocfs2_mknod+0xee4/0x22b0 fs/ocfs2/namei.c:356
       ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
       vfs_mkdir+0x408/0x620 fs/namei.c:5410
       filename_mkdirat+0x289/0x520 fs/namei.c:5443
       __do_sys_mkdirat fs/namei.c:5464 [inline]
       __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal#5){.+.+}-{0:0}:
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs/super.h:19 [inline]
       sb_start_intwrite include/linux/fs/super.h:177 [inline]
       ocfs2_start_trans+0x2ac/0x700 fs/ocfs2/journal.c:367
       ocfs2_xattr_set+0xe9c/0x13a0 fs/ocfs2/xattr.c:3892
       __vfs_removexattr+0x41c/0x450 fs/xattr.c:544
       __vfs_removexattr_locked+0xe2/0x280 fs/xattr.c:579
       vfs_removexattr+0x7f/0x230 fs/xattr.c:601
       ovl_do_removexattr fs/overlayfs/overlayfs.h:342 [inline]
       ovl_removexattr fs/overlayfs/overlayfs.h:350 [inline]
       ovl_make_workdir fs/overlayfs/super.c:756 [inline]
       ovl_get_workdir+0xe0e/0x1980 fs/overlayfs/super.c:836
       ovl_fill_super_creds fs/overlayfs/super.c:1449 [inline]
       ovl_fill_super+0x1702/0x4360 fs/overlayfs/super.c:1561
       vfs_get_super fs/super.c:1405 [inline]
       get_tree_nodev+0xbb/0x150 fs/super.c:1424
       vfs_get_tree+0x92/0x2a0 fs/super.c:1947
       fc_mount fs/namespace.c:1198 [inline]
       do_new_mount_fc fs/namespace.c:3772 [inline]
       do_new_mount+0x319/0xdc0 fs/namespace.c:3848
       do_mount fs/namespace.c:4181 [inline]
       __do_sys_mount fs/namespace.c:4397 [inline]
       __se_sys_mount+0x31d/0x420 fs/namespace.c:4374
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&oi->ip_xattr_sem){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3209 [inline]
       check_prevs_add kernel/locking/lockdep.c:3328 [inline]
       validate_chain kernel/locking/lockdep.c:3952 [inline]
       __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
       lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
       down_read+0x97/0x200 kernel/locking/rwsem.c:1574
       ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578
       __vfs_getxattr+0x412/0x440 fs/xattr.c:446
       smk_fetch+0xb4/0x140 security/smack/smack_lsm.c:298
       smack_d_instantiate+0x757/0x990 security/smack/smack_lsm.c:3679
       security_d_instantiate+0x106/0x1d0 security/security.c:3703
       d_instantiate+0x54/0xb0 fs/dcache.c:2176
       ocfs2_mknod+0x1acb/0x22b0 fs/ocfs2/namei.c:459
       ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
       vfs_mkdir+0x408/0x620 fs/namei.c:5410
       filename_mkdirat+0x289/0x520 fs/namei.c:5443
       __do_sys_mkdirat fs/namei.c:5464 [inline]
       __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &oi->ip_xattr_sem --> sb_internal#5 --> &journal->j_trans_barrier

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&journal->j_trans_barrier);
                               lock(sb_internal#5);
                               lock(&journal->j_trans_barrier);
  rlock(&oi->ip_xattr_sem);

 *** DEADLOCK ***

locks held by syz.0.129/6766: 8, last CPU#1:
 #0: ffff888060eac510 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
 #1: ffff88805fd57000 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
 #1: ffff88805fd57000 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
 #1: ffff88805fd57000 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
 #1: ffff88805fd57000 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092
 #2: ffff88804e43bdc0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
 #2: ffff88804e43bdc0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x170/0x4850 fs/ocfs2/suballoc.c:904
 #3: ffff88804e43ce80 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
 #3: ffff88804e43ce80 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x170/0x4850 fs/ocfs2/suballoc.c:904
 #4: ffff88804e439c40 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
 #4: ffff88804e439c40 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_local_alloc_bits+0x11f/0x2680 fs/ocfs2/localalloc.c:636
 #5: ffff888060eac800 (sb_internal#5){.+.+}-{0:0}, at: ocfs2_mknod+0xf72/0x22b0 fs/ocfs2/namei.c:370
 #6: ffff88802aa5d118 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3af/0x700 fs/ocfs2/journal.c:369
 #7: ffff888029128bb0 (jbd2_handle#2){.+.+}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444

stack backtrace:
CPU: 1 UID: 0 PID: 6766 Comm: syz.0.129 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087
 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219
 check_prev_add kernel/locking/lockdep.c:3209 [inline]
 check_prevs_add kernel/locking/lockdep.c:3328 [inline]
 validate_chain kernel/locking/lockdep.c:3952 [inline]
 __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 down_read+0x97/0x200 kernel/locking/rwsem.c:1574
 ocfs2_xattr_get+0xf4/0x260 fs/ocfs2/xattr.c:1578
 __vfs_getxattr+0x412/0x440 fs/xattr.c:446
 smk_fetch+0xb4/0x140 security/smack/smack_lsm.c:298
 smack_d_instantiate+0x757/0x990 security/smack/smack_lsm.c:3679
 security_d_instantiate+0x106/0x1d0 security/security.c:3703
 d_instantiate+0x54/0xb0 fs/dcache.c:2176
 ocfs2_mknod+0x1acb/0x22b0 fs/ocfs2/namei.c:459
 ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667
 vfs_mkdir+0x408/0x620 fs/namei.c:5410
 filename_mkdirat+0x289/0x520 fs/namei.c:5443
 __do_sys_mkdirat fs/namei.c:5464 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f461db9cfc7
Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007f461bdf5e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f461bdf5ee0 RCX: 00007f461db9cfc7
RDX: 00000000000001ff RSI: 00002000000005c0 RDI: 00000000ffffff9c
RBP: 0000200000000b00 R08: 0000200000000140 R09: 0000000000000000
R10: 0000200000000b00 R11: 0000000000000246 R12: 00002000000005c0
R13: 00007f461bdf5ea0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
ocfs2: Unknown parameter 'sb'

Crashes (383):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/11 19:53 upstream 08df884136f1 b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 18:27 upstream 08df884136f1 b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 16:48 upstream 08df884136f1 b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 16:17 upstream 08df884136f1 b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 14:02 upstream 08df884136f1 b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 09:18 upstream 08df884136f1 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 07:46 upstream 08df884136f1 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 04:17 upstream 08df884136f1 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 01:54 upstream 08df884136f1 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/11 00:09 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 22:44 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 20:02 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 19:13 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 17:46 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 15:07 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 12:57 upstream 50d05c7c76c9 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 06:54 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 05:47 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 03:37 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/10 00:01 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 22:58 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 21:53 upstream 893e11787f78 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 14:42 upstream 5acbae5f7eb3 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 11:00 upstream 5acbae5f7eb3 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 09:36 upstream 5acbae5f7eb3 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 01:35 upstream 5acbae5f7eb3 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/09 00:12 upstream 5acbae5f7eb3 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 22:42 upstream 5acbae5f7eb3 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 21:35 upstream 5acbae5f7eb3 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 20:17 upstream 5acbae5f7eb3 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 14:45 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 11:06 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 09:52 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 09:03 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 08:00 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/08 05:43 upstream 28924df2a08f 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 13:53 upstream df2908090cda 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 11:04 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 09:43 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 07:29 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 03:43 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/07 01:21 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/06 22:49 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/09/06 21:14 upstream 1fc5a74b108f 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/08/27 16:37 upstream 73e3f0710014 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/08/24 22:42 upstream 0a0d1d55dad5 b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
2026/08/23 19:38 upstream 388b607d107c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs possible deadlock in ocfs2_xattr_get
* Struck through repros no longer work on HEAD.