REISERFS (device loop0): Using tea hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.396/5903 is trying to acquire lock:
ffff88801fac4090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27

but task is already holding lock:
ffff88807bb84460 (sb_writers#14){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2522 [inline]
ffff88807bb84460 (sb_writers#14){.+.+}-{0:0}, at: iterate_dir+0x482/0x560 fs/readdir.c:70

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sb_writers#14){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1811 [inline]
       sb_start_write+0x4f/0x1c0 include/linux/fs.h:1881
       mnt_want_write_file+0x5c/0x200 fs/namespace.c:430
       reiserfs_ioctl+0x10a/0x330 fs/reiserfs/ioctl.c:103
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
       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 (&sbi->lock){+.+.}-{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
       __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
       reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27
       reiserfs_dirty_inode+0x10d/0x260 fs/reiserfs/super.c:704
       __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480
       generic_update_time fs/inode.c:1881 [inline]
       inode_update_time fs/inode.c:1894 [inline]
       touch_atime+0x3b6/0x640 fs/inode.c:1966
       file_accessed include/linux/fs.h:2522 [inline]
       iterate_dir+0x482/0x560 fs/readdir.c:70
       __do_sys_getdents64 fs/readdir.c:369 [inline]
       __se_sys_getdents64+0xf2/0x270 fs/readdir.c:354
       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:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sb_writers#14);
                               lock(&sbi->lock);
                               lock(sb_writers#14);
  lock(&sbi->lock);

 *** DEADLOCK ***

3 locks held by syz.0.396/5903:
 #0: ffff8880780e8af0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1056
 #1: ffff8880746f37e0 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: iterate_dir+0x10d/0x560 fs/readdir.c:55
 #2: ffff88807bb84460 (sb_writers#14){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2522 [inline]
 #2: ffff88807bb84460 (sb_writers#14){.+.+}-{0:0}, at: iterate_dir+0x482/0x560 fs/readdir.c:70

stack backtrace:
CPU: 0 PID: 5903 Comm: syz.0.396 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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
 __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
 reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27
 reiserfs_dirty_inode+0x10d/0x260 fs/reiserfs/super.c:704
 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480
 generic_update_time fs/inode.c:1881 [inline]
 inode_update_time fs/inode.c:1894 [inline]
 touch_atime+0x3b6/0x640 fs/inode.c:1966
 file_accessed include/linux/fs.h:2522 [inline]
 iterate_dir+0x482/0x560 fs/readdir.c:70
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0xf2/0x270 fs/readdir.c:354
 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: 0033:0x7fdf96fbbdd9
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:00007fdf95215028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fdf97234fa0 RCX: 00007fdf96fbbdd9
RDX: 000000000000004f RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007fdf97051d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdf97235038 R14: 00007fdf97234fa0 R15: 00007fff966c6da8
 </TASK>