syzbot

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.5.4172/24060 is trying to acquire lock:
ffff8880723ed108 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880723ed108 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742

but task is already holding lock:
ffff888072358660 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x362/0x1580 fs/ocfs2/file.c:467

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       ocfs2_create_local_dquot+0x1a5/0x18e0 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7c6/0xb20 fs/ocfs2/quota_global.c:871
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8c8/0x25b0 fs/ocfs2/namei.c:310
       ocfs2_create+0x1b6/0x4b0 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x1181/0x2ee0 fs/namei.c:3788
       do_filp_open+0x1f1/0x430 fs/namei.c:3818
       do_sys_openat2+0x150/0x4b0 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_openat fs/open.c:1352 [inline]
       __se_sys_openat fs/open.c:1347 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1347
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #3 (&dquot->dq_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747
       dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
       ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6811
       mark_dquot_dirty fs/quota/dquot.c:372 [inline]
       mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
       __dquot_alloc_space+0x5fc/0xe60 fs/quota/dquot.c:1752
       dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline]
       dquot_alloc_space include/linux/quotaops.h:313 [inline]
       dquot_alloc_block include/linux/quotaops.h:337 [inline]
       ext4_mb_new_blocks+0xf8d/0x4760 fs/ext4/mballoc.c:5736
       ext4_ext_map_blocks+0x195b/0x6810 fs/ext4/extents.c:4346
       ext4_map_blocks+0x9de/0x1b70 fs/ext4/inode.c:679
       ext4_getblk+0x1cc/0x6f0 fs/ext4/inode.c:890
       ext4_bread+0x26/0x170 fs/ext4/inode.c:946
       ext4_append+0x2be/0x560 fs/ext4/namei.c:83
       ext4_init_new_dir+0x2b8/0x570 fs/ext4/namei.c:3030
       ext4_mkdir+0x4fb/0xce0 fs/ext4/namei.c:3076
       vfs_mkdir+0x387/0x570 fs/namei.c:4114
       do_mkdirat+0x1d8/0x440 fs/namei.c:4139
       __do_sys_mkdirat fs/namei.c:4154 [inline]
       __se_sys_mkdirat fs/namei.c:4152 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4152
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&ei->i_data_sem){++++}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       ext4_truncate+0x999/0x1240 fs/ext4/inode.c:4290
       ext4_setattr+0x10cb/0x19f0 fs/ext4/inode.c:5649
       notify_change+0xc74/0xf40 fs/attr.c:499
       do_truncate+0x1ac/0x240 fs/open.c:65
       do_sys_ftruncate+0x312/0x3c0 fs/open.c:193
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (jbd2_handle){++++}-{0:0}:
       jbd2_journal_lock_updates+0xa8/0x390 fs/jbd2/transaction.c:880
       __ocfs2_flush_truncate_log+0x2cf/0x1220 fs/ocfs2/alloc.c:6029
       ocfs2_flush_truncate_log+0x4b/0x60 fs/ocfs2/alloc.c:6076
       ocfs2_sync_fs+0x119/0x330 fs/ocfs2/super.c:402
       sync_filesystem+0x1be/0x220 fs/sync.c:66
       generic_shutdown_super+0x6b/0x340 fs/super.c:474
       kill_block_super+0x7c/0xe0 fs/super.c:1470
       deactivate_locked_super+0x93/0xf0 fs/super.c:332
       cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191
       task_work_run+0x1d0/0x260 kernel/task_work.c:203
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
       exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
       __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
       syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
       do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{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+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
       lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742
       ocfs2_commit_truncate+0xb8f/0x1de0 fs/ocfs2/alloc.c:7353
       ocfs2_truncate_file+0xd37/0x1580 fs/ocfs2/file.c:505
       ocfs2_setattr+0x16b8/0x1d30 fs/ocfs2/file.c:1212
       notify_change+0xc74/0xf40 fs/attr.c:499
       do_truncate+0x1ac/0x240 fs/open.c:65
       handle_truncate fs/namei.c:3293 [inline]
       do_open fs/namei.c:3638 [inline]
       path_openat+0x2861/0x2ee0 fs/namei.c:3791
       do_filp_open+0x1f1/0x430 fs/namei.c:3818
       do_sys_openat2+0x150/0x4b0 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_creat fs/open.c:1414 [inline]
       __se_sys_creat fs/open.c:1408 [inline]
       __x64_sys_creat+0x8c/0xb0 fs/open.c:1408
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8 --> &dquot->dq_lock --> &ocfs2_quota_ip_alloc_sem_key

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_quota_ip_alloc_sem_key);
                               lock(&dquot->dq_lock);
                               lock(&ocfs2_quota_ip_alloc_sem_key);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8);

 *** DEADLOCK ***

3 locks held by syz.5.4172/24060:
 #0: ffff888060778460 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff8880723589c8 (&sb->s_type->i_mutex_key#30){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff8880723589c8 (&sb->s_type->i_mutex_key#30){+.+.}-{3:3}, at: do_truncate+0x198/0x240 fs/open.c:63
 #2: ffff888072358660 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x362/0x1580 fs/ocfs2/file.c:467

stack backtrace:
CPU: 1 PID: 24060 Comm: syz.5.4172 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x296/0x330 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+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 ocfs2_remove_btree_range+0x674/0x15e0 fs/ocfs2/alloc.c:5742
 ocfs2_commit_truncate+0xb8f/0x1de0 fs/ocfs2/alloc.c:7353
 ocfs2_truncate_file+0xd37/0x1580 fs/ocfs2/file.c:505
 ocfs2_setattr+0x16b8/0x1d30 fs/ocfs2/file.c:1212
 notify_change+0xc74/0xf40 fs/attr.c:499
 do_truncate+0x1ac/0x240 fs/open.c:65
 handle_truncate fs/namei.c:3293 [inline]
 do_open fs/namei.c:3638 [inline]
 path_openat+0x2861/0x2ee0 fs/namei.c:3791
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_creat fs/open.c:1414 [inline]
 __se_sys_creat fs/open.c:1408 [inline]
 __x64_sys_creat+0x8c/0xb0 fs/open.c:1408
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f89cf39c799
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:00007f89d0297028 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f89cf616090 RCX: 00007f89cf39c799
RDX: 0000000000000000 RSI: 000000000000000d RDI: 0000200000000240
RBP: 00007f89cf432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f89cf616128 R14: 00007f89cf616090 R15: 00007ffeed6bbcb8
 </TASK>