EXT4-fs (loop5): mounted filesystem without journal. Quota mode: writeback.
ext4 filesystem being mounted at /18/file1 supports timestamps until 2038-01-19 (0x7fffffff)
======================================================
WARNING: possible circular locking dependency detected
6.1.119-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.1458/11916 is trying to acquire lock:
ffff888067f05ca8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x57/0x510 fs/quota/dquot.c:507

but task is already holding lock:
ffff888071fa3eb8 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x955/0x1cb0 fs/ext4/inode.c:671

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&ei->i_data_sem/2){++++}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
       ext4_map_blocks+0x379/0x1cb0 fs/ext4/inode.c:603
       ext4_getblk+0x1eb/0x7c0 fs/ext4/inode.c:889
       ext4_bread+0x2a/0x170 fs/ext4/inode.c:945
       ext4_quota_write+0x21e/0x570 fs/ext4/super.c:7171
       write_blk fs/quota/quota_tree.c:70 [inline]
       get_free_dqblk+0x340/0x6c0 fs/quota/quota_tree.c:136
       do_insert_tree+0x298/0x1440 fs/quota/quota_tree.c:347
       do_insert_tree+0xb94/0x1440 fs/quota/quota_tree.c:402
       do_insert_tree+0xb94/0x1440 fs/quota/quota_tree.c:402
       do_insert_tree+0xb94/0x1440 fs/quota/quota_tree.c:402
       dq_insert_tree fs/quota/quota_tree.c:432 [inline]
       qtree_write_dquot+0x483/0x5a0 fs/quota/quota_tree.c:451
       v2_write_dquot+0x11c/0x190 fs/quota/quota_v2.c:361
       dquot_acquire+0x34d/0x680 fs/quota/dquot.c:472
       ext4_acquire_dquot+0x2eb/0x4a0 fs/ext4/super.c:6797
       dqget+0x762/0xe90 fs/quota/dquot.c:986
       __dquot_initialize+0x2d9/0xea0 fs/quota/dquot.c:1515
       ext4_process_orphan+0x57/0x2d0 fs/ext4/orphan.c:329
       ext4_orphan_cleanup+0xb70/0x1400 fs/ext4/orphan.c:474
       __ext4_fill_super fs/ext4/super.c:5534 [inline]
       ext4_fill_super+0x83ff/0x8b50 fs/ext4/super.c:5665
       get_tree_bdev+0x3fe/0x620 fs/super.c:1366
       vfs_get_tree+0x88/0x270 fs/super.c:1573
       do_new_mount+0x2ba/0xb40 fs/namespace.c:3056
       do_mount fs/namespace.c:3399 [inline]
       __do_sys_mount fs/namespace.c:3607 [inline]
       __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3584
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
       v2_read_dquot+0x4a/0x100 fs/quota/quota_v2.c:335
       dquot_acquire+0x188/0x680 fs/quota/dquot.c:463
       ext4_acquire_dquot+0x2eb/0x4a0 fs/ext4/super.c:6797
       dqget+0x762/0xe90 fs/quota/dquot.c:986
       __dquot_initialize+0x2d9/0xea0 fs/quota/dquot.c:1515
       ext4_create+0xb1/0x550 fs/ext4/namei.c:2876
       lookup_open fs/namei.c:3482 [inline]
       open_last_lookups fs/namei.c:3550 [inline]
       path_openat+0x12f1/0x2e60 fs/namei.c:3780
       do_filp_open+0x230/0x480 fs/namei.c:3810
       do_sys_openat2+0x13b/0x4f0 fs/open.c:1318
       do_sys_open fs/open.c:1334 [inline]
       __do_sys_openat fs/open.c:1350 [inline]
       __se_sys_openat fs/open.c:1345 [inline]
       __x64_sys_openat+0x243/0x290 fs/open.c:1345
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&dquot->dq_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
       dquot_commit+0x57/0x510 fs/quota/dquot.c:507
       ext4_write_dquot+0x1fd/0x360 fs/ext4/super.c:6777
       mark_dquot_dirty fs/quota/dquot.c:372 [inline]
       mark_all_dquot_dirty+0xf7/0x400 fs/quota/dquot.c:412
       __dquot_alloc_space+0xb68/0x10e0 fs/quota/dquot.c:1750
       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+0x1302/0x4b80 fs/ext4/mballoc.c:5727
       ext4_ext_map_blocks+0x1c1c/0x7ab0 fs/ext4/extents.c:4339
       ext4_map_blocks+0xa2b/0x1cb0 fs/ext4/inode.c:678
       _ext4_get_block+0x23b/0x660 fs/ext4/inode.c:821
       ext4_block_write_begin+0x631/0x1400 fs/ext4/inode.c:1123
       ext4_write_begin+0x638/0xf80
       generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3845
       ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:285
       ext4_file_write_iter+0x1d7/0x1930
       call_write_iter include/linux/fs.h:2265 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x857/0xbc0 fs/read_write.c:584
       ksys_write+0x19c/0x2c0 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &dquot->dq_lock --> &s->s_dquot.dqio_sem --> &ei->i_data_sem/2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem/2);
                               lock(&s->s_dquot.dqio_sem);
                               lock(&ei->i_data_sem/2);
  lock(&dquot->dq_lock);

 *** DEADLOCK ***

5 locks held by syz.5.1458/11916:
 #0: ffff888074c800e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1031
 #1: ffff88806676c460 (sb_writers#4){++++}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580
 #2: ffff888071fa4030 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #2: ffff888071fa4030 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xaf/0x3a0 fs/ext4/file.c:279
 #3: ffff888071fa3eb8 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x955/0x1cb0 fs/ext4/inode.c:671
 #4: ffffffff8d472828 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #4: ffffffff8d472828 (dquot_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
 #4: ffffffff8d472828 (dquot_srcu){....}-{0:0}, at: __dquot_alloc_space+0x1d6/0x10e0 fs/quota/dquot.c:1714

stack backtrace:
CPU: 0 PID: 11916 Comm: syz.5.1458 Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 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+0x1661/0x5950 kernel/locking/lockdep.c:3825
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
 dquot_commit+0x57/0x510 fs/quota/dquot.c:507
 ext4_write_dquot+0x1fd/0x360 fs/ext4/super.c:6777
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0xf7/0x400 fs/quota/dquot.c:412
 __dquot_alloc_space+0xb68/0x10e0 fs/quota/dquot.c:1750
 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+0x1302/0x4b80 fs/ext4/mballoc.c:5727
 ext4_ext_map_blocks+0x1c1c/0x7ab0 fs/ext4/extents.c:4339
 ext4_map_blocks+0xa2b/0x1cb0 fs/ext4/inode.c:678
 _ext4_get_block+0x23b/0x660 fs/ext4/inode.c:821
 ext4_block_write_begin+0x631/0x1400 fs/ext4/inode.c:1123
 ext4_write_begin+0x638/0xf80
 generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3845
 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:285
 ext4_file_write_iter+0x1d7/0x1930
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x857/0xbc0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd393d7e819
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:00007fd394c23038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd393f35fa0 RCX: 00007fd393d7e819
RDX: 00000000000101bf RSI: 0000000020000380 RDI: 0000000000000006
RBP: 00007fd393df175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd393f35fa0 R15: 00007ffc214c8a78
 </TASK>