REISERFS (device loop1): checking transaction log (loop1)
REISERFS (device loop1): Using r5 hash to sort names
REISERFS (device loop1): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.1.108/4911 is trying to acquire lock:
ffff888078bd6460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:446

but task is already holding lock:
ffff8880241b8090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sbi->lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747
       reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27
       reiserfs_dirty_inode+0xf0/0x240 fs/reiserfs/super.c:704
       __mark_inode_dirty+0x2eb/0xe90 fs/fs-writeback.c:2443
       generic_update_time fs/inode.c:1946 [inline]
       inode_update_time fs/inode.c:1959 [inline]
       touch_atime+0x3a7/0x620 fs/inode.c:2031
       file_accessed include/linux/fs.h:2600 [inline]
       iterate_dir+0x47c/0x560 fs/readdir.c:70
       __do_sys_getdents64 fs/readdir.c:369 [inline]
       __se_sys_getdents64+0xe5/0x260 fs/readdir.c:354
       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

-> #0 (sb_writers#13){.+.+}-{0:0}:
       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
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1891 [inline]
       sb_start_write+0x4d/0x1c0 include/linux/fs.h:1966
       mnt_want_write_file+0x5c/0x200 fs/namespace.c:446
       reiserfs_ioctl+0x10a/0x330 fs/reiserfs/ioctl.c:103
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
       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:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->lock);
                               lock(sb_writers#13);
                               lock(&sbi->lock);
  lock(sb_writers#13);

 *** DEADLOCK ***

1 lock held by syz.1.108/4911:
 #0: ffff8880241b8090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27

stack backtrace:
CPU: 0 PID: 4911 Comm: syz.1.108 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
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1891 [inline]
 sb_start_write+0x4d/0x1c0 include/linux/fs.h:1966
 mnt_want_write_file+0x5c/0x200 fs/namespace.c:446
 reiserfs_ioctl+0x10a/0x330 fs/reiserfs/ioctl.c:103
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 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: 0033:0x7f36d4b8f749
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:00007f36d5b08038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f36d4de5fa0 RCX: 00007f36d4b8f749
RDX: 0000200000000080 RSI: 0000000040087602 RDI: 0000000000000004
RBP: 00007f36d4c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f36d4de6038 R14: 00007f36d4de5fa0 R15: 00007fff02e46d58
 </TASK>