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possible deadlock in ocfs2_remove_inode (2)

Status: upstream: reported on 2025/01/20 17:05
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+ddde294b94666bb51266@syzkaller.appspotmail.com
First crash: 4d06h, last: 4d06h
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] possible deadlock in ocfs2_remove_inode (2) 0 (1) 2025/01/20 17:05
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in ocfs2_remove_inode ocfs2 1 112d 108d 0/28 auto-obsoleted due to no activity on 2025/01/08 06:54

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0 Not tainted
------------------------------------------------------
syz.3.1383/16527 is trying to acquire lock:
ffff8880840ec2c0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
ffff8880840ec2c0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{4:4}, at: ocfs2_remove_inode+0x15c/0x8a0 fs/ocfs2/inode.c:655

but task is already holding lock:
ffff8880840ea640 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
ffff8880840ea640 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{4:4}, at: ocfs2_wipe_inode+0x2e6/0x1220 fs/ocfs2/inode.c:776

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{4:4}:
       down_write+0x93/0x200 kernel/locking/rwsem.c:1577
       inode_lock include/linux/fs.h:818 [inline]
       ocfs2_del_inode_from_orphan+0x112/0x700 fs/ocfs2/namei.c:2728
       ocfs2_dio_end_io_write+0x2cc/0xf30 fs/ocfs2/aops.c:2329
       ocfs2_dio_end_io+0x139/0x2a0 fs/ocfs2/aops.c:2427
       dio_complete+0x21b/0x8e0 fs/direct-io.c:281
       __blockdev_direct_IO+0x3412/0x40b0 fs/direct-io.c:1303
       ocfs2_direct_IO+0x263/0x360 fs/ocfs2/aops.c:2464
       generic_file_direct_write+0x19a/0x410 mm/filemap.c:3969
       __generic_file_write_iter+0x11b/0x240 mm/filemap.c:4133
       ocfs2_file_write_iter+0xbd0/0x21d0 fs/ocfs2/file.c:2469
       do_iter_readv_writev+0x535/0x7f0 fs/read_write.c:820
       vfs_writev+0x363/0xdd0 fs/read_write.c:1050
       do_pwritev+0x1b1/0x270 fs/read_write.c:1146
       __do_sys_pwritev2 fs/read_write.c:1204 [inline]
       __se_sys_pwritev2 fs/read_write.c:1195 [inline]
       __x64_sys_pwritev2+0xef/0x160 fs/read_write.c:1195
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}:
       down_write+0x93/0x200 kernel/locking/rwsem.c:1577
       ocfs2_create_local_dquot+0x158/0xb40 fs/ocfs2/quota_local.c:1232
       ocfs2_acquire_dquot+0x628/0xaf0 fs/ocfs2/quota_global.c:878
       dqget+0x694/0x1160 fs/quota/dquot.c:977
       dquot_set_dqblk+0x2b/0x1230 fs/quota/dquot.c:2820
       quota_setquota+0x4c8/0x5f0 fs/quota/quota.c:310
       do_quotactl+0xb00/0x13d0 fs/quota/quota.c:802
       __do_sys_quotactl fs/quota/quota.c:961 [inline]
       __se_sys_quotactl fs/quota/quota.c:917 [inline]
       __x64_sys_quotactl+0x1b4/0x440 fs/quota/quota.c:917
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&dquot->dq_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
       wait_on_dquot fs/quota/dquot.c:354 [inline]
       dqget+0x5f2/0x1160 fs/quota/dquot.c:972
       __dquot_initialize+0x588/0xd50 fs/quota/dquot.c:1505
       ocfs2_get_init_inode+0xe8/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x93f/0x2440 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x185/0x450 fs/ocfs2/namei.c:657
       vfs_mkdir+0x580/0x860 fs/namei.c:4311
       do_mkdirat+0x301/0x3a0 fs/namei.c:4334
       __do_sys_mkdirat fs/namei.c:4349 [inline]
       __se_sys_mkdirat fs/namei.c:4347 [inline]
       __x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4347
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
       down_write+0x93/0x200 kernel/locking/rwsem.c:1577
       inode_lock include/linux/fs.h:818 [inline]
       ocfs2_remove_inode+0x15c/0x8a0 fs/ocfs2/inode.c:655
       ocfs2_wipe_inode+0x455/0x1220 fs/ocfs2/inode.c:818
       ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
       ocfs2_evict_inode+0x6da/0x1610 fs/ocfs2/inode.c:1216
       evict+0x40c/0x960 fs/inode.c:796
       iput_final fs/inode.c:1946 [inline]
       iput fs/inode.c:1972 [inline]
       iput+0x52a/0x890 fs/inode.c:1958
       ocfs2_dentry_iput+0x13a/0x340 fs/ocfs2/dcache.c:411
       dentry_unlink_inode+0x282/0x480 fs/dcache.c:420
       __dentry_kill+0x1d0/0x600 fs/dcache.c:625
       dput.part.0+0x4b1/0x9b0 fs/dcache.c:867
       dput+0x1f/0x30 fs/dcache.c:857
       __fput+0x515/0xb60 fs/file_table.c:458
       task_work_run+0x151/0x250 kernel/task_work.c:239
       resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
       __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
       syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
       do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4 --> &ocfs2_quota_ip_alloc_sem_key --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]);
                               lock(&ocfs2_quota_ip_alloc_sem_key);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4);

 *** DEADLOCK ***

2 locks held by syz.3.1383/16527:
 #0: ffff88806127cbd0 (&osb->nfs_sync_rwlock){.+.+}-{4:4}, at: ocfs2_nfs_sync_lock+0xe5/0x2e0 fs/ocfs2/dlmglue.c:2876
 #1: ffff8880840ea640 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
 #1: ffff8880840ea640 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{4:4}, at: ocfs2_wipe_inode+0x2e6/0x1220 fs/ocfs2/inode.c:776

stack backtrace:
CPU: 1 UID: 0 PID: 16527 Comm: syz.3.1383 Not tainted 6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 down_write+0x93/0x200 kernel/locking/rwsem.c:1577
 inode_lock include/linux/fs.h:818 [inline]
 ocfs2_remove_inode+0x15c/0x8a0 fs/ocfs2/inode.c:655
 ocfs2_wipe_inode+0x455/0x1220 fs/ocfs2/inode.c:818
 ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
 ocfs2_evict_inode+0x6da/0x1610 fs/ocfs2/inode.c:1216
 evict+0x40c/0x960 fs/inode.c:796
 iput_final fs/inode.c:1946 [inline]
 iput fs/inode.c:1972 [inline]
 iput+0x52a/0x890 fs/inode.c:1958
 ocfs2_dentry_iput+0x13a/0x340 fs/ocfs2/dcache.c:411
 dentry_unlink_inode+0x282/0x480 fs/dcache.c:420
 __dentry_kill+0x1d0/0x600 fs/dcache.c:625
 dput.part.0+0x4b1/0x9b0 fs/dcache.c:867
 dput+0x1f/0x30 fs/dcache.c:857
 __fput+0x515/0xb60 fs/file_table.c:458
 task_work_run+0x151/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc4a9785d29
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:00007fff1350af08 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000009e9e5 RCX: 00007fc4a9785d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fc4a9977ba0 R08: 0000000000000001 R09: 00007fff1350b1ff
R10: 00007fc4a9600000 R11: 0000000000000246 R12: 000000000009f0ae
R13: 00007fc4a9975fa0 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/16 17:03 upstream 619f0b6fad52 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in ocfs2_remove_inode
* Struck through repros no longer work on HEAD.