syzbot

loop0: detected capacity change from 0 to 32768
debugfs: Directory 'B1DE653C5FFC4D88B33B244AAB9EB3E9' with parent 'ocfs2' already present!
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.315/5812 is trying to acquire lock:
ffff88807422d108 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff88807422d108 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
ffff88807422d108 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: __ocfs2_move_extents_range+0x1a61/0x3370 fs/ocfs2/move_extents.c:860

but task is already holding lock:
ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_move_extent fs/ocfs2/move_extents.c:632 [inline]
ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: __ocfs2_move_extents_range+0x136d/0x3370 fs/ocfs2/move_extents.c:860

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       __ocfs2_flush_truncate_log+0x34f/0x11d0 fs/ocfs2/alloc.c:6047
       ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6077
       ocfs2_sync_fs+0x113/0x310 fs/ocfs2/super.c:402
       sync_filesystem+0x1be/0x220 fs/sync.c:66
       ocfs2_remount+0xf2/0xa40 fs/ocfs2/super.c:611
       reconfigure_super+0x219/0x880 fs/super.c:977
       do_remount fs/namespace.c:2741 [inline]
       path_mount+0xdfd/0x1010 fs/namespace.c:3400
       do_mount fs/namespace.c:3421 [inline]
       __do_sys_mount fs/namespace.c:3629 [inline]
       __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606
       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 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}:
       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
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
       __ocfs2_move_extents_range+0x1a61/0x3370 fs/ocfs2/move_extents.c:860
       ocfs2_move_extents+0x37c/0x960 fs/ocfs2/move_extents.c:932
       ocfs2_ioctl_move_extents+0x4da/0x6b0 fs/ocfs2/move_extents.c:1058
       ocfs2_ioctl+0x2d7/0x740 fs/ocfs2/ioctl.c:930
       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(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);

 *** DEADLOCK ***

5 locks held by syz.0.315/5812:
 #0: ffff888074cfa460 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:446
 #1: ffff88807422df48 (&sb->s_type->i_mutex_key#28){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff88807422df48 (&sb->s_type->i_mutex_key#28){+.+.}-{3:3}, at: ocfs2_move_extents+0x1a0/0x960 fs/ocfs2/move_extents.c:910
 #2: ffff88807422dbe0 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_move_extents+0x36f/0x960 fs/ocfs2/move_extents.c:930
 #3: ffff888074229808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #3: ffff888074229808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x162/0x4630 fs/ocfs2/suballoc.c:782
 #4: ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #4: ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: ocfs2_move_extent fs/ocfs2/move_extents.c:632 [inline]
 #4: ffff8880741bed88 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#6){+.+.}-{3:3}, at: __ocfs2_move_extents_range+0x136d/0x3370 fs/ocfs2/move_extents.c:860

stack backtrace:
CPU: 0 PID: 5812 Comm: syz.0.315 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
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
 __ocfs2_move_extents_range+0x1a61/0x3370 fs/ocfs2/move_extents.c:860
 ocfs2_move_extents+0x37c/0x960 fs/ocfs2/move_extents.c:932
 ocfs2_ioctl_move_extents+0x4da/0x6b0 fs/ocfs2/move_extents.c:1058
 ocfs2_ioctl+0x2d7/0x740 fs/ocfs2/ioctl.c:930
 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: 0033:0x7f0c4d38f749
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:00007f0c4e24e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0c4d5e6180 RCX: 00007f0c4d38f749
RDX: 00002000000000c0 RSI: 0000000040406f06 RDI: 0000000000000006
RBP: 00007f0c4d413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0c4d5e6218 R14: 00007f0c4d5e6180 R15: 00007fff184a7f58
 </TASK>