possible deadlock in vfs_rename (3)

Status: upstream: reported on 2026/11/10 05:03
Reported-by: syzbot+3332023eb1eef00edb2a@syzkaller.appspotmail.com
First crash: 11h01m, last: 11h00m
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in vfs_rename 4 13 603d 916d 0/3 auto-obsoleted due to no activity on 2025/06/25 12:29
upstream possible deadlock in vfs_rename kernel 4 1 1371d 1371d 0/29 closed as invalid on 2023/02/08 16:28
upstream possible deadlock in vfs_rename (3) prio:high ocfs2 4 syz, C error 5 21d 47d 0/29 upstream: reported C repro on 2026/09/23 18:33
linux-6.1 possible deadlock in vfs_rename (2) origin:lts-only 4 syz, C inconclusive 32 16h47m 679d 0/3 upstream: reported C repro on 2024/12/31 00:31
linux-5.15 possible deadlock in vfs_rename (2) 4 1 462d 462d 0/3 auto-obsoleted due to no activity on 2025/11/13 14:59
linux-6.1 possible deadlock in vfs_rename 4 8 784d 819d 0/3 auto-obsoleted due to no activity on 2024/12/25 19:29
linux-6.6 possible deadlock in vfs_rename 4 1 359d 359d 0/2 auto-obsoleted due to no activity on 2026/02/24 07:36
upstream possible deadlock in vfs_rename (2) ntfs3 4 3 662d 710d 0/29 auto-obsoleted due to no activity on 2025/04/27 15:12

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.312/5482 is trying to acquire lock:
ffff88805e3542c8 (&sb->s_type->i_mutex_key#22){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline]
ffff88805e3542c8 (&sb->s_type->i_mutex_key#22){+.+.}-{3:3}, at: vfs_rename+0x865/0x10f0 fs/namei.c:-1

but task is already holding lock:
ffff88805e353488 (&sb->s_type->i_mutex_key#22/2){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:828 [inline]
ffff88805e353488 (&sb->s_type->i_mutex_key#22/2){+.+.}-{3:3}, at: vfs_rename+0x7b1/0x10f0 fs/namei.c:4846

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&sb->s_type->i_mutex_key#22/2){+.+.}-{3:3}:
       down_write_nested+0x3b/0x60 kernel/locking/rwsem.c:1667
       inode_lock_nested include/linux/fs.h:828 [inline]
       __ocfs2_reflink+0xca4/0x16d0 fs/ocfs2/refcounttree.c:4230
       ocfs2_reflink+0x4e4/0x920 fs/ocfs2/refcounttree.c:4329
       ocfs2_vfs_reflink+0x333/0x450 fs/ocfs2/refcounttree.c:4455
       ocfs2_reflink_ioctl+0x39c/0x440 fs/ocfs2/refcounttree.c:4495
       ocfs2_ioctl+0x586/0x7a0 fs/ocfs2/ioctl.c:913
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&oi->ip_alloc_sem){++++}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_inode_lock_for_extent_tree+0xd6/0x190 fs/ocfs2/file.c:2213
       ocfs2_prepare_inode_for_write fs/ocfs2/file.c:2269 [inline]
       ocfs2_file_write_iter+0x6c6/0x1ee0 fs/ocfs2/file.c:2454
       call_write_iter include/linux/fs.h:2179 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0x748/0xd70 fs/read_write.c:594
       ksys_pwrite64 fs/read_write.c:701 [inline]
       __do_sys_pwrite64 fs/read_write.c:711 [inline]
       __se_sys_pwrite64 fs/read_write.c:708 [inline]
       __x64_sys_pwrite64+0x197/0x220 fs/read_write.c:708
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&sb->s_type->i_mutex_key#22){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3120 [inline]
       check_prevs_add kernel/locking/lockdep.c:3239 [inline]
       validate_chain kernel/locking/lockdep.c:3855 [inline]
       __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120
       lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:793 [inline]
       vfs_rename+0x865/0x10f0 fs/namei.c:-1
       do_renameat2+0x9e9/0xf70 fs/namei.c:5036
       __do_sys_rename fs/namei.c:5082 [inline]
       __se_sys_rename fs/namei.c:5080 [inline]
       __x64_sys_rename+0x82/0x90 fs/namei.c:5080
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  &sb->s_type->i_mutex_key#22 --> &oi->ip_alloc_sem --> &sb->s_type->i_mutex_key#22/2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#22/2);
                               lock(&oi->ip_alloc_sem);
                               lock(&sb->s_type->i_mutex_key#22/2);
  lock(&sb->s_type->i_mutex_key#22);

 *** DEADLOCK ***

5 locks held by syz.2.312/5482:
 #0: ffff88807d4de460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff88807d4de748 (&type->s_vfs_rename_key#5){+.+.}-{3:3}, at: lock_rename fs/namei.c:3067 [inline]
 #1: ffff88807d4de748 (&type->s_vfs_rename_key#5){+.+.}-{3:3}, at: do_renameat2+0x4aa/0xf70 fs/namei.c:4975
 #2: ffff88805e1eed88 (&type->i_mutex_dir_key#9/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:828 [inline]
 #2: ffff88805e1eed88 (&type->i_mutex_dir_key#9/1){+.+.}-{3:3}, at: lock_two_directories fs/namei.c:-1 [inline]
 #2: ffff88805e1eed88 (&type->i_mutex_dir_key#9/1){+.+.}-{3:3}, at: lock_rename fs/namei.c:3068 [inline]
 #2: ffff88805e1eed88 (&type->i_mutex_dir_key#9/1){+.+.}-{3:3}, at: do_renameat2+0x541/0xf70 fs/namei.c:4975
 #3: ffff88805e355108 (&sb->s_type->i_mutex_key#22/5){+.+.}-{3:3}, at: lock_rename include/linux/fs.h:-1 [inline]
 #3: ffff88805e355108 (&sb->s_type->i_mutex_key#22/5){+.+.}-{3:3}, at: do_renameat2+0x57c/0xf70 fs/namei.c:4975
 #4: ffff88805e353488 (&sb->s_type->i_mutex_key#22/2){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:828 [inline]
 #4: ffff88805e353488 (&sb->s_type->i_mutex_key#22/2){+.+.}-{3:3}, at: vfs_rename+0x7b1/0x10f0 fs/namei.c:4846

stack backtrace:
CPU: 0 PID: 5482 Comm: syz.2.312 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3120 [inline]
 check_prevs_add kernel/locking/lockdep.c:3239 [inline]
 validate_chain kernel/locking/lockdep.c:3855 [inline]
 __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120
 lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737
 down_write+0x38/0x60 kernel/locking/rwsem.c:1551
 inode_lock include/linux/fs.h:793 [inline]
 vfs_rename+0x865/0x10f0 fs/namei.c:-1
 do_renameat2+0x9e9/0xf70 fs/namei.c:5036
 __do_sys_rename fs/namei.c:5082 [inline]
 __se_sys_rename fs/namei.c:5080 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5080
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f14272c1f19
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:00007f142550f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f142753efa0 RCX: 00007f14272c1f19
RDX: 0000000000000000 RSI: 0000200000002440 RDI: 0000200000002340
RBP: 00007f1427350f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f142753f038 R14: 00007f142753efa0 R15: 00007ffe00723bb8
 </TASK>
(syz.2.312,5482,0):ocfs2_double_lock:1190 ERROR: status = -2
(syz.2.312,5482,0):ocfs2_rename:1299 ERROR: status = -2
(syz.2.312,5482,0):ocfs2_rename:1689 ERROR: status = -2
syz.2.312 (5482) used greatest stack depth: 18240 bytes left

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/10 05:03 linux-5.15.y 29c6cdaac04a 70ec0380 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in vfs_rename
2026/11/10 05:03 linux-5.15.y 29c6cdaac04a 70ec0380 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in vfs_rename
* Struck through repros no longer work on HEAD.