loop1: detected capacity change from 0 to 512 EXT4-fs (loop1): feature flags set on rev 0 fs, running e2fsck is recommended ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.277/5158 is trying to acquire lock: ffff0000f65e0288 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x278/0x1770 fs/ext4/inode.c:604 but task is already holding lock: ffff0000c39b6208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_read_dquot+0x4c/0x118 fs/quota/quota_v2.c:335 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x64/0x304 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4c/0x118 fs/quota/quota_v2.c:335 dquot_acquire+0x120/0x4e0 fs/quota/dquot.c:463 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6805 dqget+0x654/0xccc fs/quota/dquot.c:988 __dquot_initialize+0x264/0xa80 fs/quota/dquot.c:1517 dquot_initialize fs/quota/dquot.c:1579 [inline] dquot_file_open+0x90/0xc8 fs/quota/dquot.c:2228 ext4_file_open+0x200/0x510 fs/ext4/file.c:869 do_dentry_open+0x730/0xfa8 fs/open.c:882 vfs_open+0x7c/0x90 fs/open.c:1015 do_open fs/namei.c:3634 [inline] path_openat+0x1f48/0x2680 fs/namei.c:3791 do_filp_open+0x174/0x344 fs/namei.c:3818 do_sys_openat2+0x128/0x3d8 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x120/0x154 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 (&dquot->dq_lock){+.+.}-{3:3}: __mutex_lock_common+0x190/0x1f38 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+0x50/0x1c4 fs/quota/dquot.c:507 ext4_write_dquot+0x1b4/0x31c fs/ext4/super.c:6785 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6862 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412 __dquot_alloc_space+0x560/0xce8 fs/quota/dquot.c:1752 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+0xd30/0x435c fs/ext4/mballoc.c:5722 ext4_ext_map_blocks+0x1340/0x56c8 fs/ext4/extents.c:4340 ext4_map_blocks+0x860/0x1770 fs/ext4/inode.c:679 ext4_getblk+0x170/0x654 fs/ext4/inode.c:890 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:946 ext4_append+0x238/0x474 fs/ext4/namei.c:83 ext4_add_entry+0x770/0xbb0 fs/ext4/namei.c:2511 ext4_add_nondir+0x98/0x244 fs/ext4/namei.c:2845 ext4_create+0x2a0/0x3fc fs/ext4/namei.c:2891 lookup_open fs/namei.c:3490 [inline] open_last_lookups fs/namei.c:3558 [inline] path_openat+0x112c/0x2680 fs/namei.c:3788 do_filp_open+0x174/0x344 fs/namei.c:3818 do_sys_openat2+0x128/0x3d8 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x120/0x154 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 (&ei->i_data_sem/2){++++}-{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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 down_read+0x64/0x304 kernel/locking/rwsem.c:1520 ext4_map_blocks+0x278/0x1770 fs/ext4/inode.c:604 ext4_getblk+0x170/0x654 fs/ext4/inode.c:890 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:946 ext4_quota_read+0x160/0x350 fs/ext4/super.c:7150 read_blk fs/quota/quota_tree.c:61 [inline] find_tree_dqentry+0x174/0xc04 fs/quota/quota_tree.c:671 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x454/0x724 fs/quota/quota_tree.c:736 v2_read_dquot+0xbc/0x118 fs/quota/quota_v2.c:336 dquot_acquire+0x120/0x4e0 fs/quota/dquot.c:463 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6805 dqget+0x654/0xccc fs/quota/dquot.c:988 __dquot_initialize+0x264/0xa80 fs/quota/dquot.c:1517 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1579 ext4_process_orphan+0x5c/0x2b4 fs/ext4/orphan.c:325 ext4_orphan_cleanup+0x908/0x104c fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5530 [inline] ext4_fill_super+0x6440/0x68a8 fs/ext4/super.c:5661 get_tree_bdev+0x358/0x544 fs/super.c:1366 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5691 vfs_get_tree+0x90/0x274 fs/super.c:1573 do_new_mount+0x228/0x810 fs/namespace.c:3078 path_mount+0x5b4/0xe78 fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount fs/namespace.c:3606 [inline] __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3606 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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: &ei->i_data_sem/2 --> &dquot->dq_lock --> &s->s_dquot.dqio_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&s->s_dquot.dqio_sem); lock(&dquot->dq_lock); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); *** DEADLOCK *** 3 locks held by syz.1.277/5158: #0: ffff0000c39b60e0 (&type->s_umount_key#26/1){+.+.}-{3:3}, at: alloc_super+0x1a4/0x804 fs/super.c:228 #1: ffff0000f644e428 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_acquire+0x60/0x4e0 fs/quota/dquot.c:460 #2: ffff0000c39b6208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_read_dquot+0x4c/0x118 fs/quota/quota_v2.c:335 stack backtrace: CPU: 0 PID: 5158 Comm: syz.1.277 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x240/0x2d4 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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 down_read+0x64/0x304 kernel/locking/rwsem.c:1520 ext4_map_blocks+0x278/0x1770 fs/ext4/inode.c:604 ext4_getblk+0x170/0x654 fs/ext4/inode.c:890 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:946 ext4_quota_read+0x160/0x350 fs/ext4/super.c:7150 read_blk fs/quota/quota_tree.c:61 [inline] find_tree_dqentry+0x174/0xc04 fs/quota/quota_tree.c:671 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_tree_dqentry+0x4f8/0xc04 fs/quota/quota_tree.c:698 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x454/0x724 fs/quota/quota_tree.c:736 v2_read_dquot+0xbc/0x118 fs/quota/quota_v2.c:336 dquot_acquire+0x120/0x4e0 fs/quota/dquot.c:463 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6805 dqget+0x654/0xccc fs/quota/dquot.c:988 __dquot_initialize+0x264/0xa80 fs/quota/dquot.c:1517 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1579 ext4_process_orphan+0x5c/0x2b4 fs/ext4/orphan.c:325 ext4_orphan_cleanup+0x908/0x104c fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5530 [inline] ext4_fill_super+0x6440/0x68a8 fs/ext4/super.c:5661 get_tree_bdev+0x358/0x544 fs/super.c:1366 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5691 vfs_get_tree+0x90/0x274 fs/super.c:1573 do_new_mount+0x228/0x810 fs/namespace.c:3078 path_mount+0x5b4/0xe78 fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount fs/namespace.c:3606 [inline] __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3606 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 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 warning (device loop1): ext4_update_dynamic_rev:1086: updating to rev 1 because of new feature flag, running e2fsck is recommended EXT4-fs error (device loop1): ext4_validate_block_bitmap:438: comm syz.1.277: bg 0: block 248: padding at end of block bitmap is not set __quota_error: 32 callbacks suppressed Quota error (device loop1): write_blk: dquota write failed Quota error (device loop1): qtree_write_dquot: Error -117 occurred while creating quota EXT4-fs error (device loop1): ext4_acquire_dquot:6809: comm syz.1.277: Failed to acquire dquot type 1 EXT4-fs (loop1): 1 truncate cleaned up EXT4-fs (loop1): mounted filesystem without journal. Quota mode: writeback.