syzbot

======================================================
WARNING: possible circular locking dependency detected
5.15.183-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.1006/7572 is trying to acquire lock:
ffff88805ee985e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507

but task is already holding lock:
ffff888049112060 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&ei->i_data_sem){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ext4_truncate+0x96d/0x10d0 fs/ext4/inode.c:4245
       ext4_setattr+0xffe/0x19e0 fs/ext4/inode.c:5582
       notify_change+0xbcd/0xee0 fs/attr.c:505
       do_truncate+0x197/0x220 fs/open.c:65
       do_sys_ftruncate+0x31b/0x3d0 fs/open.c:193
       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

-> #4 (jbd2_handle){++++}-{0:0}:
       start_this_handle+0x1338/0x15a0 fs/jbd2/transaction.c:464
       jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
       jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:560
       ocfs2_start_trans+0x374/0x6c0 fs/ocfs2/journal.c:376
       ocfs2_shutdown_local_alloc+0x1fd/0xa10 fs/ocfs2/localalloc.c:416
       ocfs2_dismount_volume+0x1de/0x880 fs/ocfs2/super.c:1885
       generic_shutdown_super+0x130/0x300 fs/super.c:475
       kill_block_super+0x7c/0xe0 fs/super.c:1427
       deactivate_locked_super+0x93/0xf0 fs/super.c:335
       cleanup_mnt+0x418/0x4d0 fs/namespace.c:1143
       task_work_run+0x125/0x1a0 kernel/task_work.c:188
       tracehook_notify_resume include/linux/tracehook.h:189 [inline]
       exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
       syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
       do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #3 (&journal->j_trans_barrier){.+.+}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_start_trans+0x368/0x6c0 fs/ocfs2/journal.c:374
       ocfs2_shutdown_local_alloc+0x1fd/0xa10 fs/ocfs2/localalloc.c:416
       ocfs2_dismount_volume+0x1de/0x880 fs/ocfs2/super.c:1885
       generic_shutdown_super+0x130/0x300 fs/super.c:475
       kill_block_super+0x7c/0xe0 fs/super.c:1427
       deactivate_locked_super+0x93/0xf0 fs/super.c:335
       cleanup_mnt+0x418/0x4d0 fs/namespace.c:1143
       task_work_run+0x125/0x1a0 kernel/task_work.c:188
       tracehook_notify_resume include/linux/tracehook.h:189 [inline]
       exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
       syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
       do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #2 (sb_internal#4){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1811 [inline]
       sb_start_intwrite include/linux/fs.h:1928 [inline]
       ocfs2_start_trans+0x269/0x6c0 fs/ocfs2/journal.c:372
       ocfs2_acquire_dquot+0x677/0xaf0 fs/ocfs2/quota_global.c:848
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_symlink+0xbec/0x25d0 fs/ocfs2/namei.c:1875
       vfs_symlink+0x247/0x3d0 fs/namei.c:4429
       do_symlinkat+0x1be/0x6c0 fs/namei.c:4458
       __do_sys_symlinkat fs/namei.c:4475 [inline]
       __se_sys_symlinkat fs/namei.c:4472 [inline]
       __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4472
       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

-> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_create_local_dquot+0x194/0x1750 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7cb/0xaf0 fs/ocfs2/quota_global.c:871
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_symlink+0xbec/0x25d0 fs/ocfs2/namei.c:1875
       vfs_symlink+0x247/0x3d0 fs/namei.c:4429
       do_symlinkat+0x1be/0x6c0 fs/namei.c:4458
       __do_sys_symlinkat fs/namei.c:4475 [inline]
       __se_sys_symlinkat fs/namei.c:4472 [inline]
       __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4472
       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 (&dquot->dq_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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
       ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6180
       mark_dquot_dirty fs/quota/dquot.c:372 [inline]
       mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
       __dquot_alloc_space+0x5d0/0xe20 fs/quota/dquot.c:1752
       dquot_alloc_space_nodirty include/linux/quotaops.h:297 [inline]
       dquot_alloc_space include/linux/quotaops.h:310 [inline]
       dquot_alloc_block include/linux/quotaops.h:334 [inline]
       ext4_mb_new_blocks+0xf68/0x4940 fs/ext4/mballoc.c:5739
       ext4_ext_map_blocks+0x146c/0x64e0 fs/ext4/extents.c:4339
       ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673
       ext4_iomap_alloc fs/ext4/inode.c:3408 [inline]
       ext4_iomap_begin+0x807/0xb80 fs/ext4/inode.c:3458
       iomap_iter+0x620/0xdb0 fs/iomap/iter.c:74
       __iomap_dio_rw+0x1014/0x1a70 fs/iomap/direct-io.c:585
       iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:672
       ext4_dio_write_iter fs/ext4/file.c:540 [inline]
       ext4_file_write_iter+0x132b/0x17b0 fs/ext4/file.c:660
       do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1
       do_iter_write+0x205/0x7b0 fs/read_write.c:855
       iter_file_splice_write+0x65f/0xc40 fs/splice.c:689
       do_splice_from fs/splice.c:767 [inline]
       direct_splice_actor+0xe1/0x130 fs/splice.c:936
       splice_direct_to_actor+0x4dc/0xb50 fs/splice.c:891
       do_splice_direct+0x1b9/0x2c0 fs/splice.c:979
       do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
       __do_sys_sendfile64 fs/read_write.c:1317 [inline]
       __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
       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:

Chain exists of:
  &dquot->dq_lock --> jbd2_handle --> &ei->i_data_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem);
                               lock(jbd2_handle);
                               lock(&ei->i_data_sem);
  lock(&dquot->dq_lock);

 *** DEADLOCK ***

4 locks held by syz.0.1006/7572:
 #0: ffff88814c568460 (sb_writers#5){.+.+}-{0:0}, at: do_sendfile+0x5b2/0xec0 fs/read_write.c:1248
 #1: ffff8880491121d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff8880491121d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_dio_write_checks fs/ext4/file.c:422 [inline]
 #1: ffff8880491121d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_dio_write_iter fs/ext4/file.c:490 [inline]
 #1: ffff8880491121d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_file_write_iter+0xe2d/0x17b0 fs/ext4/file.c:660
 #2: ffff888049112060 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666
 #3: ffffffff8c23fc58 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 0 PID: 7572 Comm: syz.0.1006 Not tainted 5.15.183-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6180
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
 __dquot_alloc_space+0x5d0/0xe20 fs/quota/dquot.c:1752
 dquot_alloc_space_nodirty include/linux/quotaops.h:297 [inline]
 dquot_alloc_space include/linux/quotaops.h:310 [inline]
 dquot_alloc_block include/linux/quotaops.h:334 [inline]
 ext4_mb_new_blocks+0xf68/0x4940 fs/ext4/mballoc.c:5739
 ext4_ext_map_blocks+0x146c/0x64e0 fs/ext4/extents.c:4339
 ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673
 ext4_iomap_alloc fs/ext4/inode.c:3408 [inline]
 ext4_iomap_begin+0x807/0xb80 fs/ext4/inode.c:3458
 iomap_iter+0x620/0xdb0 fs/iomap/iter.c:74
 __iomap_dio_rw+0x1014/0x1a70 fs/iomap/direct-io.c:585
 iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:672
 ext4_dio_write_iter fs/ext4/file.c:540 [inline]
 ext4_file_write_iter+0x132b/0x17b0 fs/ext4/file.c:660
 do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1
 do_iter_write+0x205/0x7b0 fs/read_write.c:855
 iter_file_splice_write+0x65f/0xc40 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0xe1/0x130 fs/splice.c:936
 splice_direct_to_actor+0x4dc/0xb50 fs/splice.c:891
 do_splice_direct+0x1b9/0x2c0 fs/splice.c:979
 do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
 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: 0033:0x7f8ba9874969
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:00007f8ba76dc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f8ba9a9bfa0 RCX: 00007f8ba9874969
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 00007f8ba98f6ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8ba9a9bfa0 R15: 00007ffdffa279a8
 </TASK>