ext4 filesystem being mounted at /153/bus supports timestamps until 2038-01-19 (0x7fffffff)
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.1.736/7224 is trying to acquire lock:
ffff888060a50268 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507

but task is already holding lock:
ffff888060ac2060 (&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_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666
       mpage_map_one_extent fs/ext4/inode.c:2408 [inline]
       mpage_map_and_submit_extent fs/ext4/inode.c:2461 [inline]
       ext4_writepages+0x12ca/0x2d20 fs/ext4/inode.c:2829
       do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386
       __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657
       writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1940
       __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
       wb_writeback+0x455/0xb90 fs/fs-writeback.c:2116
       wb_check_background_flush fs/fs-writeback.c:2182 [inline]
       wb_do_writeback fs/fs-writeback.c:2270 [inline]
       wb_workfn+0xb47/0xe60 fs/fs-writeback.c:2298
       process_one_work+0x863/0x1000 kernel/workqueue.c:2310
       worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
       kthread+0x436/0x520 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #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_update_inode_atime+0xf1/0x540 fs/ocfs2/file.c:257
       ocfs2_inode_lock_atime+0x30f/0x4e0 fs/ocfs2/dlmglue.c:2606
       ocfs2_readdir+0x187/0x460 fs/ocfs2/dir.c:1954
       iterate_dir+0x218/0x560 fs/readdir.c:-1
       __do_sys_getdents64 fs/readdir.c:369 [inline]
       __se_sys_getdents64+0xe5/0x260 fs/readdir.c:354
       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

-> #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_update_inode_atime+0xf1/0x540 fs/ocfs2/file.c:257
       ocfs2_inode_lock_atime+0x30f/0x4e0 fs/ocfs2/dlmglue.c:2606
       ocfs2_readdir+0x187/0x460 fs/ocfs2/dir.c:1954
       iterate_dir+0x218/0x560 fs/readdir.c:-1
       __do_sys_getdents64 fs/readdir.c:369 [inline]
       __se_sys_getdents64+0xe5/0x260 fs/readdir.c:354
       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

-> #2 (sb_internal#2){.+.+}-{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_mknod+0x8aa/0x22b0 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x192/0x410 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1d7/0x5a0 fs/namei.c:4098
       __do_sys_mkdirat fs/namei.c:4113 [inline]
       __se_sys_mkdirat fs/namei.c:4111 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
       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_mknod+0x8aa/0x22b0 fs/ocfs2/namei.c:310
       ocfs2_mkdir+0x192/0x410 fs/ocfs2/namei.c:657
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1d7/0x5a0 fs/namei.c:4098
       __do_sys_mkdirat fs/namei.c:4113 [inline]
       __se_sys_mkdirat fs/namei.c:4111 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
       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:6185
       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:5734
       ext4_ext_map_blocks+0x191a/0x6650 fs/ext4/extents.c:4341
       ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673
       _ext4_get_block+0x1d7/0x4e0 fs/ext4/inode.c:816
       ext4_block_write_begin+0x60f/0x1210 fs/ext4/inode.c:1101
       ext4_write_begin+0x6c2/0x15c0 fs/ext4/ext4_jbd2.h:-1
       ext4_da_write_begin+0x435/0xb30 fs/ext4/inode.c:2975
       __page_symlink+0xf6/0x1f0 fs/namei.c:5199
       ext4_symlink+0x880/0xcc0 fs/ext4/namei.c:3467
       vfs_symlink+0x247/0x3d0 fs/namei.c:4437
       do_symlinkat+0x1be/0x6c0 fs/namei.c:4466
       __do_sys_symlink fs/namei.c:4488 [inline]
       __se_sys_symlink fs/namei.c:4486 [inline]
       __x64_sys_symlink+0x7a/0x90 fs/namei.c:4486
       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.1.736/7224:
 #0: ffff888078da0460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff88807564c9b8 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #1: ffff88807564c9b8 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3843
 #2: ffff888060ac2060 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666
 #3: ffffffff8c23f118 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312

stack backtrace:
CPU: 1 PID: 7224 Comm: syz.1.736 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 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:6185
 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:5734
 ext4_ext_map_blocks+0x191a/0x6650 fs/ext4/extents.c:4341
 ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673
 _ext4_get_block+0x1d7/0x4e0 fs/ext4/inode.c:816
 ext4_block_write_begin+0x60f/0x1210 fs/ext4/inode.c:1101
 ext4_write_begin+0x6c2/0x15c0 fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x435/0xb30 fs/ext4/inode.c:2975
 __page_symlink+0xf6/0x1f0 fs/namei.c:5199
 ext4_symlink+0x880/0xcc0 fs/ext4/namei.c:3467
 vfs_symlink+0x247/0x3d0 fs/namei.c:4437
 do_symlinkat+0x1be/0x6c0 fs/namei.c:4466
 __do_sys_symlink fs/namei.c:4488 [inline]
 __se_sys_symlink fs/namei.c:4486 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4486
 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: 0033:0x7fcaf757a6c9
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:00007fcaf57e1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fcaf77d0fa0 RCX: 00007fcaf757a6c9
RDX: 0000000000000000 RSI: 0000200000000800 RDI: 0000200000000540
RBP: 00007fcaf75fcf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcaf77d1038 R14: 00007fcaf77d0fa0 R15: 00007ffc3020b3a8
 </TASK>