syzbot


possible deadlock in ocfs2_del_inode_from_orphan (3)

Status: upstream: reported on 2025/11/25 22:40
Reported-by: syzbot+b6e6a2ef620b522176e7@syzkaller.appspotmail.com
First crash: 115d, last: 3d10h
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in ocfs2_del_inode_from_orphan (2) 4 11 11d 143d 0/3 upstream: reported on 2025/10/29 05:09
linux-6.6 possible deadlock in ocfs2_del_inode_from_orphan origin:upstream 4 C 80 2h17m 267d 0/2 upstream: reported C repro on 2025/06/26 20:15
linux-5.15 possible deadlock in ocfs2_del_inode_from_orphan 4 1 439d 439d 0/3 auto-obsoleted due to no activity on 2025/04/16 07:13
linux-5.15 possible deadlock in ocfs2_del_inode_from_orphan (2) 4 1 270d 270d 0/3 auto-obsoleted due to no activity on 2025/10/01 09:47
linux-6.1 possible deadlock in ocfs2_del_inode_from_orphan 4 4 369d 464d 0/3 auto-obsoleted due to no activity on 2025/06/25 04:24
upstream possible deadlock in ocfs2_del_inode_from_orphan ocfs2 4 C inconclusive 6857 15m 534d 2/29 upstream: reported C repro on 2024/10/03 02:18

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.3313/15748 is trying to acquire lock:
ffff888050889808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
ffff888050889808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}, at: ocfs2_del_inode_from_orphan+0x12b/0x7a0 fs/ocfs2/namei.c:2713

but task is already holding lock:
ffff8880510d94a0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io_write fs/ocfs2/aops.c:2325 [inline]
ffff8880510d94a0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io+0x434/0x1200 fs/ocfs2/aops.c:2431

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_create_local_dquot+0x199/0x1850 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7ed/0xb10 fs/ocfs2/quota_global.c:871
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8ab/0x2510 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x192/0x420 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1df/0x5b0 fs/namei.c:4098
       __do_sys_mkdirat fs/namei.c:4113 [inline]
       __se_sys_mkdirat fs/namei.c:4111 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
       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

-> #2 (&dquot->dq_lock){+.+.}-{3:3}:
       __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       wait_on_dquot fs/quota/dquot.c:356 [inline]
       dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
       __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8ab/0x2510 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x192/0x420 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1df/0x5b0 fs/namei.c:4098
       __do_sys_mkdirat fs/namei.c:4113 [inline]
       __se_sys_mkdirat fs/namei.c:4111 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
       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 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:787 [inline]
       ocfs2_remove_inode fs/ocfs2/inode.c:655 [inline]
       ocfs2_wipe_inode fs/ocfs2/inode.c:818 [inline]
       ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
       ocfs2_evict_inode+0x1d72/0x41d0 fs/ocfs2/inode.c:1216
       evict+0x4c9/0x8d0 fs/inode.c:647
       ocfs2_dentry_iput+0x24a/0x390 fs/ocfs2/dcache.c:418
       __dentry_kill+0x431/0x650 fs/dcache.c:586
       dentry_kill+0xb8/0x290 fs/dcache.c:-1
       dput+0xd8/0x1a0 fs/dcache.c:893
       ovl_check_rename_whiteout fs/overlayfs/super.c:1313 [inline]
       ovl_make_workdir fs/overlayfs/super.c:1411 [inline]
       ovl_get_workdir+0x8e0/0x1230 fs/overlayfs/super.c:1526
       ovl_fill_super+0x1824/0x2a30 fs/overlayfs/super.c:2082
       mount_nodev+0x52/0xe0 fs/super.c:1446
       legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
       vfs_get_tree+0x88/0x270 fs/super.c:1530
       do_new_mount+0x24a/0xa40 fs/namespace.c:3034
       do_mount fs/namespace.c:3377 [inline]
       __do_sys_mount fs/namespace.c:3585 [inline]
       __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
       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 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
       lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:787 [inline]
       ocfs2_del_inode_from_orphan+0x12b/0x7a0 fs/ocfs2/namei.c:2713
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x540/0x1200 fs/ocfs2/aops.c:2431
       dio_complete+0x249/0x720 fs/direct-io.c:272
       do_blockdev_direct_IO fs/direct-io.c:1336 [inline]
       __blockdev_direct_IO+0x2e31/0x3a70 fs/direct-io.c:1368
       ocfs2_direct_IO+0x233/0x2a0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
       __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
       ocfs2_file_write_iter+0x1670/0x1e70 fs/ocfs2/file.c:2472
       do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1
       do_iter_write+0x205/0x7b0 fs/read_write.c:855
       iter_file_splice_write+0x699/0xcc0 fs/splice.c:689
       do_splice_from fs/splice.c:767 [inline]
       direct_splice_actor+0xe1/0x130 fs/splice.c:956
       splice_direct_to_actor+0x4ea/0xc10 fs/splice.c:902
       do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008
       do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249
       __do_sys_sendfile64 fs/read_write.c:1317 [inline]
       __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303
       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:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type] --> &dquot->dq_lock --> &ocfs2_quota_ip_alloc_sem_key

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_quota_ip_alloc_sem_key);
                               lock(&dquot->dq_lock);
                               lock(&ocfs2_quota_ip_alloc_sem_key);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]);

 *** DEADLOCK ***

3 locks held by syz.2.3313/15748:
 #0: ffff888079394460 (sb_writers#31){.+.+}-{0:0}, at: do_sendfile+0x5d9/0xeb0 fs/read_write.c:1248
 #1: ffff8880510d9808 (&sb->s_type->i_mutex_key#43){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff8880510d9808 (&sb->s_type->i_mutex_key#43){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x436/0x1e70 fs/ocfs2/file.c:2402
 #2: ffff8880510d94a0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io_write fs/ocfs2/aops.c:2325 [inline]
 #2: ffff8880510d94a0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io+0x434/0x1200 fs/ocfs2/aops.c:2431

stack backtrace:
CPU: 0 PID: 15748 Comm: syz.2.3313 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 down_write+0x38/0x60 kernel/locking/rwsem.c:1551
 inode_lock include/linux/fs.h:787 [inline]
 ocfs2_del_inode_from_orphan+0x12b/0x7a0 fs/ocfs2/namei.c:2713
 ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
 ocfs2_dio_end_io+0x540/0x1200 fs/ocfs2/aops.c:2431
 dio_complete+0x249/0x720 fs/direct-io.c:272
 do_blockdev_direct_IO fs/direct-io.c:1336 [inline]
 __blockdev_direct_IO+0x2e31/0x3a70 fs/direct-io.c:1368
 ocfs2_direct_IO+0x233/0x2a0 fs/ocfs2/aops.c:2468
 generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
 __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
 ocfs2_file_write_iter+0x1670/0x1e70 fs/ocfs2/file.c:2472
 do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1
 do_iter_write+0x205/0x7b0 fs/read_write.c:855
 iter_file_splice_write+0x699/0xcc0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0xe1/0x130 fs/splice.c:956
 splice_direct_to_actor+0x4ea/0xc10 fs/splice.c:902
 do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008
 do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303
 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: 0033:0x7f8ccb7d4799
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:00007f8cc9a2e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f8ccba4dfa0 RCX: 00007f8ccb7d4799
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007f8ccb86ac99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ccba4e038 R14: 00007f8ccba4dfa0 R15: 00007ffcd9ef0928
 </TASK>
syz.2.3313 (15748) used greatest stack depth: 18328 bytes left

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/17 22:39 linux-5.15.y 91d48252ad4b c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_del_inode_from_orphan
2026/02/25 03:38 linux-5.15.y 3330a8d33e08 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_del_inode_from_orphan
2025/12/05 09:31 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_del_inode_from_orphan
2025/11/25 22:39 linux-5.15.y cc5ec8769306 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_del_inode_from_orphan
* Struck through repros no longer work on HEAD.