====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 Not tainted ------------------------------------------------------ syz.0.216/7873 is trying to acquire lock: ffff0000ca758268 (&dquot->dq_lock){+.+.}-{4:4}, at: wait_on_dquot fs/quota/dquot.c:354 [inline] ffff0000ca758268 (&dquot->dq_lock){+.+.}-{4:4}, at: dqget+0x5e4/0xccc fs/quota/dquot.c:972 but task is already holding lock: ffff0000dcbdc3b8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x728/0x1810 fs/ext4/inode.c:5816 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&ei->xattr_sem){++++}-{4:4}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1577 ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline] ext4_xattr_set_handle+0x11c/0x1260 fs/ext4/xattr.c:2362 ext4_initxattrs+0xa4/0x11c fs/ext4/xattr_security.c:44 security_inode_init_security+0x6dc/0x7f4 security/security.c:1852 ext4_init_security+0x44/0x58 fs/ext4/xattr_security.c:58 __ext4_new_inode+0x2854/0x3278 fs/ext4/ialloc.c:1325 ext4_create+0x1f8/0x3fc fs/ext4/namei.c:2822 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x12d8/0x2c40 fs/namei.c:4043 do_filp_open+0x18c/0x36c fs/namei.c:4073 do_sys_openat2+0x11c/0x1b4 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x120/0x158 fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #4 (jbd2_handle){++++}-{0:0}: start_this_handle+0xe74/0x10dc fs/jbd2/transaction.c:444 jbd2__journal_start+0x288/0x51c fs/jbd2/transaction.c:501 jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:540 ocfs2_start_trans+0x368/0x6b0 fs/ocfs2/journal.c:374 ocfs2_modify_bh+0xe4/0x43c fs/ocfs2/quota_local.c:101 ocfs2_local_read_info+0x104c/0x1364 fs/ocfs2/quota_local.c:767 dquot_load_quota_sb+0x6bc/0xa90 fs/quota/dquot.c:2459 dquot_load_quota_inode+0x274/0x4e4 fs/quota/dquot.c:2496 ocfs2_enable_quotas+0x17c/0x3b4 fs/ocfs2/super.c:930 ocfs2_fill_super+0x4018/0x5340 fs/ocfs2/super.c:1140 get_tree_bdev_flags+0x360/0x414 fs/super.c:1679 get_tree_bdev+0x2c/0x3c fs/super.c:1702 ocfs2_get_tree+0x28/0x38 fs/ocfs2/super.c:1184 vfs_get_tree+0x90/0x28c fs/super.c:1802 do_new_mount+0x228/0x814 fs/namespace.c:3885 path_mount+0x5b4/0xde0 fs/namespace.c:4209 do_mount fs/namespace.c:4222 [inline] __do_sys_mount fs/namespace.c:4433 [inline] __se_sys_mount fs/namespace.c:4410 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4410 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #3 (&journal->j_trans_barrier){.+.+}-{4:4}: down_read+0x58/0x2f8 kernel/locking/rwsem.c:1524 ocfs2_start_trans+0x35c/0x6b0 fs/ocfs2/journal.c:372 ocfs2_modify_bh+0xe4/0x43c fs/ocfs2/quota_local.c:101 ocfs2_local_read_info+0x104c/0x1364 fs/ocfs2/quota_local.c:767 dquot_load_quota_sb+0x6bc/0xa90 fs/quota/dquot.c:2459 dquot_load_quota_inode+0x274/0x4e4 fs/quota/dquot.c:2496 ocfs2_enable_quotas+0x17c/0x3b4 fs/ocfs2/super.c:930 ocfs2_fill_super+0x4018/0x5340 fs/ocfs2/super.c:1140 get_tree_bdev_flags+0x360/0x414 fs/super.c:1679 get_tree_bdev+0x2c/0x3c fs/super.c:1702 ocfs2_get_tree+0x28/0x38 fs/ocfs2/super.c:1184 vfs_get_tree+0x90/0x28c fs/super.c:1802 do_new_mount+0x228/0x814 fs/namespace.c:3885 path_mount+0x5b4/0xde0 fs/namespace.c:4209 do_mount fs/namespace.c:4222 [inline] __do_sys_mount fs/namespace.c:4433 [inline] __se_sys_mount fs/namespace.c:4410 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4410 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #2 (sb_internal#3){.+.+}-{0:0}: percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1793 [inline] sb_start_intwrite include/linux/fs.h:1976 [inline] ocfs2_start_trans+0x1f4/0x6b0 fs/ocfs2/journal.c:370 ocfs2_acquire_dquot+0x594/0xa10 fs/ocfs2/quota_global.c:860 dqget+0x654/0xccc fs/quota/dquot.c:977 dquot_set_dqblk+0x40/0xe50 fs/quota/dquot.c:2820 quota_setquota+0x3b4/0x3bc fs/quota/quota.c:310 do_quotactl+0x65c/0x738 fs/quota/quota.c:802 __do_sys_quotactl_fd fs/quota/quota.c:1000 [inline] __se_sys_quotactl_fd fs/quota/quota.c:973 [inline] __arm64_sys_quotactl_fd+0x2f8/0x4d4 fs/quota/quota.c:973 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1577 ocfs2_create_local_dquot+0x164/0x1444 fs/ocfs2/quota_local.c:1227 ocfs2_acquire_dquot+0x6a8/0xa10 fs/ocfs2/quota_global.c:883 dqget+0x654/0xccc fs/quota/dquot.c:977 dquot_set_dqblk+0x40/0xe50 fs/quota/dquot.c:2820 quota_setquota+0x3b4/0x3bc fs/quota/quota.c:310 do_quotactl+0x65c/0x738 fs/quota/quota.c:802 __do_sys_quotactl_fd fs/quota/quota.c:1000 [inline] __se_sys_quotactl_fd fs/quota/quota.c:973 [inline] __arm64_sys_quotactl_fd+0x2f8/0x4d4 fs/quota/quota.c:973 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #0 (&dquot->dq_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:602 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 wait_on_dquot fs/quota/dquot.c:354 [inline] dqget+0x5e4/0xccc fs/quota/dquot.c:972 dquot_transfer+0x238/0x560 fs/quota/dquot.c:2140 ext4_setattr+0x738/0x1810 fs/ext4/inode.c:5817 notify_change+0x9a4/0xc50 fs/attr.c:552 chown_common+0x374/0x4dc fs/open.c:790 vfs_fchown fs/open.c:858 [inline] ksys_fchown+0xe0/0x158 fs/open.c:870 __do_sys_fchown fs/open.c:875 [inline] __se_sys_fchown fs/open.c:873 [inline] __arm64_sys_fchown+0x7c/0x94 fs/open.c:873 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> jbd2_handle --> &ei->xattr_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&ei->xattr_sem); lock(jbd2_handle); lock(&ei->xattr_sem); lock(&dquot->dq_lock); *** DEADLOCK *** 3 locks held by syz.0.216/7873: #0: ffff0000d07b6428 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1e8 fs/namespace.c:601 #1: ffff0000dcbdc6d0 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: inode_lock_killable include/linux/fs.h:872 [inline] #1: ffff0000dcbdc6d0 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: chown_common+0x290/0x4dc fs/open.c:778 #2: ffff0000dcbdc3b8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x728/0x1810 fs/ext4/inode.c:5816 stack backtrace: CPU: 0 UID: 0 PID: 7873 Comm: syz.0.216 Not tainted 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:501 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x324/0x32c kernel/locking/lockdep.c:2046 check_noncircular+0x154/0x174 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:602 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 wait_on_dquot fs/quota/dquot.c:354 [inline] dqget+0x5e4/0xccc fs/quota/dquot.c:972 dquot_transfer+0x238/0x560 fs/quota/dquot.c:2140 ext4_setattr+0x738/0x1810 fs/ext4/inode.c:5817 notify_change+0x9a4/0xc50 fs/attr.c:552 chown_common+0x374/0x4dc fs/open.c:790 vfs_fchown fs/open.c:858 [inline] ksys_fchown+0xe0/0x158 fs/open.c:870 __do_sys_fchown fs/open.c:875 [inline] __se_sys_fchown fs/open.c:873 [inline] __arm64_sys_fchown+0x7c/0x94 fs/open.c:873 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600