======================================================
WARNING: possible circular locking dependency detected
6.1.86-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor286/4596 is trying to acquire lock:
ffff0000e2d08b28 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x240 fs/quota/dquot.c:507

but task is already holding lock:
ffff0000e2d970e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x794/0x1850 fs/ext4/inode.c:644

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&ei->i_data_sem/2){++++}-{3:3}:
       down_read+0x64/0x308 kernel/locking/rwsem.c:1520
       ext4_map_blocks+0x2ac/0x1850 fs/ext4/inode.c:574
       ext4_getblk+0x198/0x6ec fs/ext4/inode.c:866
       ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:922
       ext4_quota_write+0x230/0x54c fs/ext4/super.c:7147
       write_blk fs/quota/quota_tree.c:64 [inline]
       get_free_dqblk+0x28c/0x598 fs/quota/quota_tree.c:130
       do_insert_tree+0x1fc/0x1474 fs/quota/quota_tree.c:340
       do_insert_tree+0x510/0x1474 fs/quota/quota_tree.c:375
       do_insert_tree+0x510/0x1474 fs/quota/quota_tree.c:375
       do_insert_tree+0x510/0x1474 fs/quota/quota_tree.c:375
       dq_insert_tree fs/quota/quota_tree.c:401 [inline]
       qtree_write_dquot+0x318/0x488 fs/quota/quota_tree.c:420
       v2_write_dquot+0xf4/0x188 fs/quota/quota_v2.c:358
       dquot_acquire+0x2c4/0x5c4 fs/quota/dquot.c:472
       ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6773
       dqget+0x660/0xcb4 fs/quota/dquot.c:986
       __dquot_initialize+0x344/0xc04 fs/quota/dquot.c:1516
       dquot_initialize+0x24/0x34 fs/quota/dquot.c:1578
       ext4_mkdir+0x15c/0xa64 fs/ext4/namei.c:3010
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4108
       do_mkdirat+0x220/0x510 fs/namei.c:4133
       __do_sys_mkdirat fs/namei.c:4148 [inline]
       __se_sys_mkdirat fs/namei.c:4146 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4146
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}:
       down_read+0x64/0x308 kernel/locking/rwsem.c:1520
       v2_read_dquot+0x50/0x11c fs/quota/quota_v2.c:332
       dquot_acquire+0x130/0x5c4 fs/quota/dquot.c:463
       ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6773
       dqget+0x660/0xcb4 fs/quota/dquot.c:986
       __dquot_initialize+0x344/0xc04 fs/quota/dquot.c:1516
       dquot_initialize+0x24/0x34 fs/quota/dquot.c:1578
       ext4_mkdir+0x15c/0xa64 fs/ext4/namei.c:3010
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4108
       do_mkdirat+0x220/0x510 fs/namei.c:4133
       __do_sys_mkdirat fs/namei.c:4148 [inline]
       __se_sys_mkdirat fs/namei.c:4146 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4146
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #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 kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
       lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
       __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
       dquot_commit+0x54/0x240 fs/quota/dquot.c:507
       ext4_write_dquot+0x1b4/0x314 fs/ext4/super.c:6753
       ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6813
       mark_dquot_dirty fs/quota/dquot.c:372 [inline]
       mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412
       __dquot_alloc_space+0xb28/0xf50 fs/quota/dquot.c:1751
       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+0xf04/0x468c fs/ext4/mballoc.c:5666
       ext4_ext_map_blocks+0x15a8/0x6644 fs/ext4/extents.c:4316
       ext4_map_blocks+0x828/0x1850 fs/ext4/inode.c:651
       ext4_getblk+0x198/0x6ec fs/ext4/inode.c:866
       ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:922
       ext4_add_entry+0x768/0xcc8 fs/ext4/namei.c:2439
       ext4_mkdir+0x43c/0xa64 fs/ext4/namei.c:3032
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4108
       do_mkdirat+0x220/0x510 fs/namei.c:4133
       __do_sys_mkdirat fs/namei.c:4148 [inline]
       __se_sys_mkdirat fs/namei.c:4146 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4146
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

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 ***

4 locks held by syz-executor286/4596:
 #0: ffff0000d2d80460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #1: ffff0000e2d97258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff0000e2d97258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x204/0x468 fs/namei.c:3878
 #2: ffff0000e2d970e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x794/0x1850 fs/ext4/inode.c:644
 #3: ffff800015b46cc8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349

stack backtrace:
CPU: 1 PID: 4596 Comm: syz-executor286 Not tainted 6.1.86-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x5c lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2048
 check_noncircular+0x2cc/0x378 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+0x3338/0x7680 kernel/locking/lockdep.c:5049
 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
 dquot_commit+0x54/0x240 fs/quota/dquot.c:507
 ext4_write_dquot+0x1b4/0x314 fs/ext4/super.c:6753
 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6813
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412
 __dquot_alloc_space+0xb28/0xf50 fs/quota/dquot.c:1751
 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+0xf04/0x468c fs/ext4/mballoc.c:5666
 ext4_ext_map_blocks+0x15a8/0x6644 fs/ext4/extents.c:4316
 ext4_map_blocks+0x828/0x1850 fs/ext4/inode.c:651
 ext4_getblk+0x198/0x6ec fs/ext4/inode.c:866
 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:922
 ext4_add_entry+0x768/0xcc8 fs/ext4/namei.c:2439
 ext4_mkdir+0x43c/0xa64 fs/ext4/namei.c:3032
 vfs_mkdir+0x334/0x4e4 fs/namei.c:4108
 do_mkdirat+0x220/0x510 fs/namei.c:4133
 __do_sys_mkdirat fs/namei.c:4148 [inline]
 __se_sys_mkdirat fs/namei.c:4146 [inline]
 __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4146
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
EXT4-fs error (device loop0): ext4_do_update_inode:5210: inode #2: comm syz-executor286: corrupted inode contents
EXT4-fs error (device loop0): ext4_dirty_inode:6072: inode #2: comm syz-executor286: mark_inode_dirty error
EXT4-fs error (device loop0): ext4_do_update_inode:5210: inode #2: comm syz-executor286: corrupted inode contents
EXT4-fs error (device loop0): __ext4_ext_dirty:202: inode #2: comm syz-executor286: mark_inode_dirty error