[syzbot] [ocfs2?] possible deadlock in ocfs2_del_inode_from_orphan (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e7ae89a0c97c Linux 7.1-rc5
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13d232a6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8d24a1331e060dda
dashboard link: https://syzkaller.appspot.com/bug?extid=0cc53e247e48f3b60f4d
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/60848c96a4f9/disk-e7ae89a0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7c3d913edd61/vmlinux-e7ae89a0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fa9417a180e6/bzImage-e7ae89a0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0cc53e...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G L
------------------------------------------------------
syz.0.2196/15247 is trying to acquire lock:
ffff8880489941a0 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
ffff8880489941a0 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_del_inode_from_orphan+0x12e/0x7a0 fs/ocfs2/namei.c:2728

but task is already holding lock:
ffff8880489933a0 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
ffff8880489933a0 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4840 fs/ocfs2/suballoc.c:882

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}:
down_write+0x96/0x200 kernel/locking/rwsem.c:1625
inode_lock include/linux/fs.h:1029 [inline]
ocfs2_reserve_suballoc_bits+0x16d/0x4840 fs/ocfs2/suballoc.c:882
ocfs2_reserve_new_metadata_blocks+0x415/0x9a0 fs/ocfs2/suballoc.c:1078
ocfs2_mknod+0x10f3/0x2260 fs/ocfs2/namei.c:351
ocfs2_mkdir+0x181/0x460 fs/ocfs2/namei.c:660
vfs_mkdir+0x413/0x630 fs/namei.c:5261
filename_mkdirat+0x285/0x510 fs/namei.c:5294
__do_sys_mkdirat fs/namei.c:5315 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5312
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}:
down_write+0x96/0x200 kernel/locking/rwsem.c:1625
inode_lock include/linux/fs.h:1029 [inline]
ocfs2_remove_inode fs/ocfs2/inode.c:733 [inline]
ocfs2_wipe_inode fs/ocfs2/inode.c:896 [inline]
ocfs2_delete_inode fs/ocfs2/inode.c:1157 [inline]
ocfs2_evict_inode+0x1539/0x43b0 fs/ocfs2/inode.c:1299
evict+0x61e/0xb10 fs/inode.c:841
ocfs2_dentry_iput+0x24d/0x390 fs/ocfs2/dcache.c:407
__dentry_kill+0x1a2/0x690 fs/dcache.c:718
finish_dput+0xc9/0x480 fs/dcache.c:927
__fput+0x691/0xa60 fs/file_table.c:518
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xf3/0x4d0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0x560 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
down_write+0x96/0x200 kernel/locking/rwsem.c:1625
inode_lock include/linux/fs.h:1029 [inline]
ocfs2_del_inode_from_orphan+0x12e/0x7a0 fs/ocfs2/namei.c:2728
ocfs2_dio_end_io_write fs/ocfs2/aops.c:2379 [inline]
ocfs2_dio_end_io+0xf9c/0x1370 fs/ocfs2/aops.c:2418
dio_complete+0x25b/0x790 fs/direct-io.c:281
__blockdev_direct_IO+0x2e5d/0x34e0 fs/direct-io.c:1303
ocfs2_direct_IO+0x251/0x2c0 fs/ocfs2/aops.c:2455
generic_file_direct_write+0x1db/0x3e0 mm/filemap.c:4259
__generic_file_write_iter+0x11d/0x230 mm/filemap.c:4428
ocfs2_file_write_iter+0x1663/0x1e70 fs/ocfs2/file.c:2476
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61d/0xb90 fs/read_write.c:688
ksys_write+0x150/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE] --> &ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE] --> &ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]);
lock(&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]);
lock(&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]);
lock(&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]);

*** DEADLOCK ***

4 locks held by syz.0.2196/15247:
#0: ffff888079d71cf0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1261
#1: ffff888050d30410 (sb_writers#26){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline]
#1: ffff888050d30410 (sb_writers#26){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684
#2: ffff88806b11eba0 (&sb->s_type->i_mutex_key#38){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#2: ffff88806b11eba0 (&sb->s_type->i_mutex_key#38){+.+.}-{4:4}, at: ocfs2_file_write_iter+0x429/0x1e70 fs/ocfs2/file.c:2406
#3: ffff8880489933a0 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
#3: ffff8880489933a0 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4840 fs/ocfs2/suballoc.c:882

stack backtrace:
CPU: 0 UID: 0 PID: 15247 Comm: syz.0.2196 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043
check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
down_write+0x96/0x200 kernel/locking/rwsem.c:1625
inode_lock include/linux/fs.h:1029 [inline]
ocfs2_del_inode_from_orphan+0x12e/0x7a0 fs/ocfs2/namei.c:2728
ocfs2_dio_end_io_write fs/ocfs2/aops.c:2379 [inline]
ocfs2_dio_end_io+0xf9c/0x1370 fs/ocfs2/aops.c:2418
dio_complete+0x25b/0x790 fs/direct-io.c:281
__blockdev_direct_IO+0x2e5d/0x34e0 fs/direct-io.c:1303
ocfs2_direct_IO+0x251/0x2c0 fs/ocfs2/aops.c:2455
generic_file_direct_write+0x1db/0x3e0 mm/filemap.c:4259
__generic_file_write_iter+0x11d/0x230 mm/filemap.c:4428
ocfs2_file_write_iter+0x1663/0x1e70 fs/ocfs2/file.c:2476
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61d/0xb90 fs/read_write.c:688
ksys_write+0x150/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efe9c19ce59
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:00007efe9d09b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007efe9c416090 RCX: 00007efe9c19ce59
RDX: 00000000ffffffd7 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007efe9c232d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efe9c416128 R14: 00007efe9c416090 R15: 00007ffdb4582448
</TASK>


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