syzbot

======================================================
WARNING: possible circular locking dependency detected
6.16.0-syzkaller-11852-g479058002c32 #0 Tainted: G        W          
------------------------------------------------------
syz.4.1960/14384 is trying to acquire lock:
ffff88803df0be80 (&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
ffff88803df0be80 (&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_lock_global_qf+0x1ca/0x270 fs/ocfs2/quota_global.c:313

but task is already holding lock:
ffff888063ce0098 (&dquot->dq_lock){+.+.}-{4:4}, at: ocfs2_acquire_dquot+0x2a3/0xb30 fs/ocfs2/quota_global.c:823

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #6 (&dquot->dq_lock){+.+.}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline]
       mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:547
       wait_on_dquot fs/quota/dquot.c:354 [inline]
       dqget+0x73a/0xf20 fs/quota/dquot.c:972
       dquot_transfer+0x2f8/0x6d0 fs/quota/dquot.c:2140
       ext4_setattr+0x865/0x1bc0 fs/ext4/inode.c:5902
       notify_change+0xb31/0xe60 fs/attr.c:552
       chown_common+0x40c/0x5c0 fs/open.c:791
       do_fchownat+0x161/0x270 fs/open.c:822
       __do_sys_fchownat fs/open.c:837 [inline]
       __se_sys_fchownat fs/open.c:834 [inline]
       __x64_sys_fchownat+0xb5/0xd0 fs/open.c:834
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #5 (&ei->xattr_sem){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
       ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
       ext4_xattr_set_handle+0x165/0x1590 fs/ext4/xattr.c:2362
       ext4_initxattrs+0x9f/0x110 fs/ext4/xattr_security.c:44
       security_inode_init_security+0x29d/0x3f0 security/security.c:1852
       __ext4_new_inode+0x3314/0x3cb0 fs/ext4/ialloc.c:1325
       ext4_create+0x22d/0x460 fs/ext4/namei.c:2822
       lookup_open fs/namei.c:3708 [inline]
       open_last_lookups fs/namei.c:3807 [inline]
       path_openat+0x14fd/0x3840 fs/namei.c:4043
       do_filp_open+0x1fa/0x410 fs/namei.c:4073
       do_sys_openat2+0x121/0x1c0 fs/open.c:1435
       do_sys_open fs/open.c:1450 [inline]
       __do_sys_openat fs/open.c:1466 [inline]
       __se_sys_openat fs/open.c:1461 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1461
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #4 (jbd2_handle){++++}-{0:0}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       start_this_handle+0x1fa7/0x21c0 fs/jbd2/transaction.c:444
       jbd2__journal_start+0x2c1/0x5b0 fs/jbd2/transaction.c:501
       jbd2_journal_start+0x2a/0x40 fs/jbd2/transaction.c:540
       ocfs2_start_trans+0x377/0x6d0 fs/ocfs2/journal.c:374
       ocfs2_shutdown_local_alloc+0x200/0xa10 fs/ocfs2/localalloc.c:417
       ocfs2_dismount_volume+0x201/0x8d0 fs/ocfs2/super.c:1825
       generic_shutdown_super+0x132/0x2c0 fs/super.c:643
       kill_block_super+0x44/0x90 fs/super.c:1766
       deactivate_locked_super+0xbc/0x130 fs/super.c:474
       get_tree_bdev_flags+0x42c/0x4d0 fs/super.c:1694
       vfs_get_tree+0x92/0x2b0 fs/super.c:1815
       do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
       do_mount fs/namespace.c:4133 [inline]
       __do_sys_mount fs/namespace.c:4344 [inline]
       __se_sys_mount+0x317/0x410 fs/namespace.c:4321
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #3 (&journal->j_trans_barrier){.+.+}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       down_read+0x97/0x1f0 kernel/locking/rwsem.c:1537
       ocfs2_start_trans+0x36b/0x6d0 fs/ocfs2/journal.c:372
       ocfs2_shutdown_local_alloc+0x200/0xa10 fs/ocfs2/localalloc.c:417
       ocfs2_dismount_volume+0x201/0x8d0 fs/ocfs2/super.c:1825
       generic_shutdown_super+0x132/0x2c0 fs/super.c:643
       kill_block_super+0x44/0x90 fs/super.c:1766
       deactivate_locked_super+0xbc/0x130 fs/super.c:474
       get_tree_bdev_flags+0x42c/0x4d0 fs/super.c:1694
       vfs_get_tree+0x92/0x2b0 fs/super.c:1815
       do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
       do_mount fs/namespace.c:4133 [inline]
       __do_sys_mount fs/namespace.c:4344 [inline]
       __se_sys_mount+0x317/0x410 fs/namespace.c:4321
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (sb_internal#2){.+.+}-{0:0}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs.h:1798 [inline]
       sb_start_intwrite include/linux/fs.h:1981 [inline]
       ocfs2_start_trans+0x26b/0x6d0 fs/ocfs2/journal.c:370
       ocfs2_write_info+0x11d/0x350 fs/ocfs2/quota_global.c:997
       quota_setinfo+0x2f9/0x310 fs/quota/quota.c:174
       __do_sys_quotactl fs/quota/quota.c:961 [inline]
       __se_sys_quotactl+0x279/0x950 fs/quota/quota.c:917
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
       ocfs2_lock_global_qf+0x1e8/0x270 fs/ocfs2/quota_global.c:314
       ocfs2_write_info+0xd6/0x350 fs/ocfs2/quota_global.c:994
       quota_setinfo+0x2f9/0x310 fs/quota/quota.c:174
       __do_sys_quotactl fs/quota/quota.c:961 [inline]
       __se_sys_quotactl+0x279/0x950 fs/quota/quota.c:917
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
       inode_lock include/linux/fs.h:869 [inline]
       ocfs2_lock_global_qf+0x1ca/0x270 fs/ocfs2/quota_global.c:313
       ocfs2_acquire_dquot+0x2b0/0xb30 fs/ocfs2/quota_global.c:828
       dqget+0x7be/0xf20 fs/quota/dquot.c:977
       __dquot_initialize+0x3b3/0xcb0 fs/quota/dquot.c:1505
       ocfs2_get_init_inode+0x13b/0x1b0 fs/ocfs2/namei.c:205
       ocfs2_symlink+0xaee/0x23e0 fs/ocfs2/namei.c:1890
       vfs_symlink+0x143/0x2f0 fs/namei.c:4730
       do_symlinkat+0x1b1/0x3f0 fs/namei.c:4756
       __do_sys_symlink fs/namei.c:4777 [inline]
       __se_sys_symlink fs/namei.c:4775 [inline]
       __x64_sys_symlink+0x7a/0x90 fs/namei.c:4775
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE] --> &ei->xattr_sem --> &dquot->dq_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&dquot->dq_lock);
                               lock(&ei->xattr_sem);
                               lock(&dquot->dq_lock);
  lock(&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]);

 *** DEADLOCK ***

4 locks held by syz.4.1960/14384:
 #0: ffff88814c5b8488 (sb_writers#17){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff88803df0ad80 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
 #1: ffff88803df0ad80 (&type->i_mutex_dir_key#14/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4139
 #2: ffff88805dd92d80 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
 #2: ffff88805dd92d80 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x15e/0x4640 fs/ocfs2/suballoc.c:788
 #3: ffff888063ce0098 (&dquot->dq_lock){+.+.}-{4:4}, at: ocfs2_acquire_dquot+0x2a3/0xb30 fs/ocfs2/quota_global.c:823

stack backtrace:
CPU: 1 UID: 0 PID: 14384 Comm: syz.4.1960 Tainted: G        W           6.16.0-syzkaller-11852-g479058002c32 #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
 inode_lock include/linux/fs.h:869 [inline]
 ocfs2_lock_global_qf+0x1ca/0x270 fs/ocfs2/quota_global.c:313
 ocfs2_acquire_dquot+0x2b0/0xb30 fs/ocfs2/quota_global.c:828
 dqget+0x7be/0xf20 fs/quota/dquot.c:977
 __dquot_initialize+0x3b3/0xcb0 fs/quota/dquot.c:1505
 ocfs2_get_init_inode+0x13b/0x1b0 fs/ocfs2/namei.c:205
 ocfs2_symlink+0xaee/0x23e0 fs/ocfs2/namei.c:1890
 vfs_symlink+0x143/0x2f0 fs/namei.c:4730
 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4756
 __do_sys_symlink fs/namei.c:4777 [inline]
 __se_sys_symlink fs/namei.c:4775 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4775
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f428702ebe9
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:00007f4284e96038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007f4287255fa0 RCX: 00007f428702ebe9
RDX: 0000000000000000 RSI: 0000200000000640 RDI: 0000200000000540
RBP: 00007f42870b1e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4287256038 R14: 00007f4287255fa0 R15: 00007ffec02aa058
 </TASK>
(syz.4.1960,14384,1):ocfs2_block_check_validate:402 ERROR: CRC32 failed: stored: 0x1cec3d0f, computed 0xd2ffbdfe. Applying ECC.
(syz.4.1960,14384,1):ocfs2_block_check_validate:402 ERROR: CRC32 failed: stored: 0xdf8356d3, computed 0xb8c23ae4. Applying ECC.
(syz.4.1960,14384,1):ocfs2_block_check_validate:416 ERROR: Fixed CRC32 failed: stored: 0xdf8356d3, computed 0x2acb7e3c
(syz.4.1960,14384,1):ocfs2_read_quota_phys_block:160 ERROR: status = -5
(syz.4.1960,14384,1):ocfs2_quota_read:201 ERROR: status = -5
(syz.4.1960,14384,1):ocfs2_acquire_dquot:890 ERROR: status = -5
(syz.4.1960,14384,1):ocfs2_symlink:1894 ERROR: status = -5
(syz.4.1960,14384,1):ocfs2_symlink:2080 ERROR: status = -5