syzbot

reiserfs: enabling write barrier flush mode
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
5.15.173-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor269/4162 is trying to acquire lock:
ffffc90002e410f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
ffffc90002e410f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline]
ffffc90002e410f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_begin_r+0x34e/0x1000 fs/reiserfs/journal.c:3045

but task is already holding lock:
ffff888028ec2460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:421

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (sb_writers#9){.+.+}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1813 [inline]
       sb_start_write+0x4f/0x1c0 include/linux/fs.h:1883
       mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:421
       reiserfs_ioctl+0x170/0x340 fs/reiserfs/ioctl.c:103
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&sbi->lock){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1da/0x25a0 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_nested+0x5b/0xd0 fs/reiserfs/lock.c:78
       reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:815 [inline]
       lock_journal fs/reiserfs/journal.c:534 [inline]
       do_journal_begin_r+0x359/0x1000 fs/reiserfs/journal.c:3045
       journal_begin+0x148/0x350 fs/reiserfs/journal.c:3253
       reiserfs_remount+0xf6b/0x18e0 fs/reiserfs/super.c:1561
       reconfigure_super+0x43a/0x870 fs/super.c:938
       do_remount fs/namespace.c:2668 [inline]
       path_mount+0xceb/0x10a0 fs/namespace.c:3334
       do_mount fs/namespace.c:3355 [inline]
       __do_sys_mount fs/namespace.c:3563 [inline]
       __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&journal->j_mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
       lock_journal fs/reiserfs/journal.c:534 [inline]
       do_journal_begin_r+0x34e/0x1000 fs/reiserfs/journal.c:3045
       journal_begin+0x148/0x350 fs/reiserfs/journal.c:3253
       reiserfs_dirty_inode+0x11c/0x240 fs/reiserfs/super.c:710
       __mark_inode_dirty+0x2fd/0xd60 fs/fs-writeback.c:2464
       mark_inode_dirty include/linux/fs.h:2469 [inline]
       reiserfs_ioctl+0x29e/0x340 fs/reiserfs/ioctl.c:111
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:874 [inline]
       __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  &journal->j_mutex --> &sbi->lock --> sb_writers#9

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sb_writers#9);
                               lock(&sbi->lock);
                               lock(sb_writers#9);
  lock(&journal->j_mutex);

 *** DEADLOCK ***

1 lock held by syz-executor269/4162:
 #0: ffff888028ec2460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:421

stack backtrace:
CPU: 0 PID: 4162 Comm: syz-executor269 Not tainted 5.15.173-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 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+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline]
 lock_journal fs/reiserfs/journal.c:534 [inline]
 do_journal_begin_r+0x34e/0x1000 fs/reiserfs/journal.c:3045
 journal_begin+0x148/0x350 fs/reiserfs/journal.c:3253
 reiserfs_dirty_inode+0x11c/0x240 fs/reiserfs/super.c:710
 __mark_inode_dirty+0x2fd/0xd60 fs/fs-writeback.c:2464
 mark_inode_dirty include/linux/fs.h:2469 [inline]
 reiserfs_ioctl+0x29e/0x340 fs/reiserfs/ioctl.c:111
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd51563cc39
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff85972cd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd515685066 RCX: 00007fd51