syzbot


possible deadlock in ocfs2_del_inode_from_orphan (2)

Status: upstream: reported on 2025/10/29 05:09
Reported-by: syzbot+c6bd0cf61bad0bb99aff@syzkaller.appspotmail.com
First crash: 8d07h, last: 8d07h
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 possible deadlock in ocfs2_del_inode_from_orphan 4 31 7h39m 132d 0/2 upstream: reported on 2025/06/26 20:15
linux-5.15 possible deadlock in ocfs2_del_inode_from_orphan 4 1 304d 304d 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 136d 136d 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 234d 329d 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 2566 15h10m 399d 0/29 upstream: reported C repro on 2024/10/03 02:18

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.4.42/4612 is trying to acquire lock:
ffff888055ad42c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff888055ad42c8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}, at: ocfs2_del_inode_from_orphan+0x131/0x730 fs/ocfs2/namei.c:2713

but task is already holding lock:
ffff888055ada2e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io_write fs/ocfs2/aops.c:2325 [inline]
ffff888055ada2e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io+0x386/0x10f0 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+0x36/0x60 kernel/locking/rwsem.c:1573
       ocfs2_create_local_dquot+0x1a0/0x1790 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7ae/0xb10 fs/ocfs2/quota_global.c:871
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8be/0x2350 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x1b6/0x4a0 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4114
       do_mkdirat+0x1d0/0x430 fs/namei.c:4139
       __do_sys_mkdirat fs/namei.c:4154 [inline]
       __se_sys_mkdirat fs/namei.c:4152 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4152
       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

-> #2 (&dquot->dq_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747
       wait_on_dquot fs/quota/dquot.c:356 [inline]
       dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
       __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8be/0x2350 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x1b6/0x4a0 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4114
       do_mkdirat+0x1d0/0x430 fs/namei.c:4139
       __do_sys_mkdirat fs/namei.c:4154 [inline]
       __se_sys_mkdirat fs/namei.c:4152 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4152
       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 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [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+0x141b/0x41f0 fs/ocfs2/inode.c:1219
       evict+0x485/0x870 fs/inode.c:705
       ocfs2_dentry_iput+0x244/0x370 fs/ocfs2/dcache.c:418
       __dentry_kill+0x431/0x650 fs/dcache.c:611
       dentry_kill+0xb8/0x290 fs/dcache.c:-1
       dput+0xfa/0x1d0 fs/dcache.c:918
       __fput+0x5e0/0x920 fs/file_table.c:328
       task_work_run+0x1ca/0x250 kernel/task_work.c:203
       get_signal+0x11a6/0x1350 kernel/signal.c:2648
       arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
       exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
       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]){+.+.}-{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_del_inode_from_orphan+0x131/0x730 fs/ocfs2/namei.c:2713
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x475/0x10f0 fs/ocfs2/aops.c:2431
       dio_complete+0x26f/0x810 fs/direct-io.c:271
       __blockdev_direct_IO+0x2e1d/0x3450 fs/direct-io.c:1326
       ocfs2_direct_IO+0x23e/0x2b0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x3be/0x660 mm/filemap.c:3770
       __generic_file_write_iter+0x1db/0x430 mm/filemap.c:3930
       ocfs2_file_write_iter+0x1593/0x1df0 fs/ocfs2/file.c:2469
       do_iter_readv_writev fs/read_write.c:-1 [inline]
       do_iter_write+0x62d/0xaf0 fs/read_write.c:861
       iter_file_splice_write+0x665/0xc50 fs/splice.c:685
       do_splice_from fs/splice.c:763 [inline]
       direct_splice_actor+0xe1/0x130 fs/splice.c:950
       splice_direct_to_actor+0x480/0xb60 fs/splice.c:896
       do_splice_direct+0x1b0/0x2b0 fs/splice.c:1002
       do_sendfile+0x5cc/0xeb0 fs/read_write.c:1255
       __do_sys_sendfile64 fs/read_write.c:1323 [inline]
       __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1309
       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] --> &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.4.42/4612:
 #0: ffff8880238de460 (sb_writers#14){.+.+}-{0:0}, at: do_sendfile+0x5a9/0xeb0 fs/read_write.c:1254
 #1: ffff888055ada648 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888055ada648 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ocfs2_file_write_iter+0x438/0x1df0 fs/ocfs2/file.c:2399
 #2: ffff888055ada2e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io_write fs/ocfs2/aops.c:2325 [inline]
 #2: ffff888055ada2e0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_dio_end_io+0x386/0x10f0 fs/ocfs2/aops.c:2431

stack backtrace:
CPU: 0 PID: 4612 Comm: syz.4.42 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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_del_inode_from_orphan+0x131/0x730 fs/ocfs2/namei.c:2713
 ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
 ocfs2_dio_end_io+0x475/0x10f0 fs/ocfs2/aops.c:2431
 dio_complete+0x26f/0x810 fs/direct-io.c:271
 __blockdev_direct_IO+0x2e1d/0x3450 fs/direct-io.c:1326
 ocfs2_direct_IO+0x23e/0x2b0 fs/ocfs2/aops.c:2468
 generic_file_direct_write+0x3be/0x660 mm/filemap.c:3770
 __generic_file_write_iter+0x1db/0x430 mm/filemap.c:3930
 ocfs2_file_write_iter+0x1593/0x1df0 fs/ocfs2/file.c:2469
 do_iter_readv_writev fs/read_write.c:-1 [inline]
 do_iter_write+0x62d/0xaf0 fs/read_write.c:861
 iter_file_splice_write+0x665/0xc50 fs/splice.c:685
 do_splice_from fs/splice.c:763 [inline]
 direct_splice_actor+0xe1/0x130 fs/splice.c:950
 splice_direct_to_actor+0x480/0xb60 fs/splice.c:896
 do_splice_direct+0x1b0/0x2b0 fs/splice.c:1002
 do_sendfile+0x5cc/0xeb0 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1309
 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: 0033:0x7fdd1618efc9
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:00007fdd170dc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fdd163e5fa0 RCX: 00007fdd1618efc9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007fdd16211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdd163e6038 R14: 00007fdd163e5fa0 R15: 00007fffc956fc28
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/29 05:08 linux-6.1.y 8e6e2188d949 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_del_inode_from_orphan
* Struck through repros no longer work on HEAD.