EXT4-fs (loop1): mounted filesystem without journal. Opts: grpquota,inode_readahead_blks=0x0000000000000800,quota,,errors=continue. Quota mode: writeback. ====================================================== WARNING: possible circular locking dependency detected 5.15.183-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.210/4960 is trying to acquire lock: ffff0000df13be48 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x288/0x167c fs/ext4/inode.c:598 but task is already holding lock: ffff0000d1ea2208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x114/0x180 fs/quota/quota_v2.c:354 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+0xc0/0x390 kernel/locking/rwsem.c:1498 v2_read_dquot+0x4c/0x118 fs/quota/quota_v2.c:332 dquot_acquire+0x120/0x510 fs/quota/dquot.c:463 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6200 dqget+0x658/0xcf4 fs/quota/dquot.c:988 __dquot_initialize+0x2d4/0xa80 fs/quota/dquot.c:1517 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1579 ext4_mkdir+0x148/0xa40 fs/ext4/namei.c:3059 vfs_mkdir+0x314/0x4d4 fs/namei.c:4065 do_mkdirat+0x1bc/0x508 fs/namei.c:4090 __do_sys_mkdirat fs/namei.c:4105 [inline] __se_sys_mkdirat fs/namei.c:4103 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #1 (&dquot->dq_lock){+.+.}-{3:3}: __mutex_lock_common+0x194/0x1edc kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xac/0x11c kernel/locking/mutex.c:743 dquot_commit+0x50/0x1c4 fs/quota/dquot.c:507 ext4_write_dquot+0x1b4/0x31c fs/ext4/super.c:6180 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6257 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412 __dquot_alloc_space+0x560/0xd0c 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+0xd30/0x4024 fs/ext4/mballoc.c:5739 ext4_ext_map_blocks+0xf70/0x5628 fs/ext4/extents.c:4339 ext4_map_blocks+0x7b8/0x167c fs/ext4/inode.c:673 ext4_getblk+0x138/0x5f0 fs/ext4/inode.c:870 ext4_bread+0x3c/0x1d4 fs/ext4/inode.c:923 ext4_append+0x238/0x474 fs/ext4/namei.c:83 ext4_init_new_dir+0x258/0x864 fs/ext4/namei.c:3030 ext4_mkdir+0x3c0/0xa40 fs/ext4/namei.c:3076 vfs_mkdir+0x314/0x4d4 fs/namei.c:4065 do_mkdirat+0x1bc/0x508 fs/namei.c:4090 __do_sys_mkdirat fs/namei.c:4105 [inline] __se_sys_mkdirat fs/namei.c:4103 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #0 (&ei->i_data_sem/2){++++}-{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+0x2928/0x651c kernel/locking/lockdep.c:5012 lock_acquire+0x1f4/0x620 kernel/locking/lockdep.c:5623 down_read+0xc0/0x390 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x288/0x167c fs/ext4/inode.c:598 ext4_getblk+0x138/0x5f0 fs/ext4/inode.c:870 ext4_bread+0x3c/0x1d4 fs/ext4/inode.c:923 ext4_quota_write+0x220/0x52c fs/ext4/super.c:6591 write_blk fs/quota/quota_tree.c:64 [inline] get_free_dqblk+0x2d4/0x680 fs/quota/quota_tree.c:125 do_insert_tree+0x1e4/0x1424 fs/quota/quota_tree.c:335 do_insert_tree+0x450/0x1424 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x2c4/0x3f8 fs/quota/quota_tree.c:411 v2_write_dquot+0xf0/0x180 fs/quota/quota_v2.c:358 dquot_acquire+0x2b0/0x510 fs/quota/dquot.c:472 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6200 dqget+0x658/0xcf4 fs/quota/dquot.c:988 dquot_transfer+0x19c/0x3cc fs/quota/dquot.c:2146 ext4_setattr+0x588/0x142c fs/ext4/inode.c:5451 notify_change+0xa08/0xcd8 fs/attr.c:505 chown_common+0x42c/0x5a0 fs/open.c:680 vfs_fchown fs/open.c:748 [inline] ksys_fchown+0xe0/0x158 fs/open.c:759 __do_sys_fchown fs/open.c:767 [inline] __se_sys_fchown fs/open.c:765 [inline] __arm64_sys_fchown+0x7c/0x94 fs/open.c:765 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 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 *** 5 locks held by syz.1.210/4960: #0: ffff0000d1ea2460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1e8 fs/namespace.c:421 #1: ffff0000df13abd0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff0000df13abd0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: chown_common+0x380/0x5a0 fs/open.c:674 #2: ffff0000df13a8a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_setattr+0x57c/0x142c fs/ext4/inode.c:5450 #3: ffff0000e8eb85e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_acquire+0x60/0x510 fs/quota/dquot.c:460 #4: ffff0000d1ea2208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x114/0x180 fs/quota/quota_v2.c:354 stack backtrace: CPU: 0 PID: 4960 Comm: syz.1.210 Not tainted 5.15.183-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __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:2011 check_noncircular+0x240/0x2d4 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+0x2928/0x651c kernel/locking/lockdep.c:5012 lock_acquire+0x1f4/0x620 kernel/locking/lockdep.c:5623 down_read+0xc0/0x390 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x288/0x167c fs/ext4/inode.c:598 ext4_getblk+0x138/0x5f0 fs/ext4/inode.c:870 ext4_bread+0x3c/0x1d4 fs/ext4/inode.c:923 ext4_quota_write+0x220/0x52c fs/ext4/super.c:6591 write_blk fs/quota/quota_tree.c:64 [inline] get_free_dqblk+0x2d4/0x680 fs/quota/quota_tree.c:125 do_insert_tree+0x1e4/0x1424 fs/quota/quota_tree.c:335 do_insert_tree+0x450/0x1424 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x2c4/0x3f8 fs/quota/quota_tree.c:411 v2_write_dquot+0xf0/0x180 fs/quota/quota_v2.c:358 dquot_acquire+0x2b0/0x510 fs/quota/dquot.c:472 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6200 dqget+0x658/0xcf4 fs/quota/dquot.c:988 dquot_transfer+0x19c/0x3cc fs/quota/dquot.c:2146 ext4_setattr+0x588/0x142c fs/ext4/inode.c:5451 notify_change+0xa08/0xcd8 fs/attr.c:505 chown_common+0x42c/0x5a0 fs/open.c:680 vfs_fchown fs/open.c:748 [inline] ksys_fchown+0xe0/0x158 fs/open.c:759 __do_sys_fchown fs/open.c:767 [inline] __se_sys_fchown fs/open.c:765 [inline] __arm64_sys_fchown+0x7c/0x94 fs/open.c:765 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584