EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. ext4 filesystem being mounted at /2104/bus supports timestamps until 2038-01-19 (0x7fffffff) ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-syzkaller-00378-gb67ec639010f #0 Not tainted ------------------------------------------------------ syz.1.12594/15813 is trying to acquire lock: ffff888053f195a8 (&dquot->dq_lock){+.+.}-{4:4}, at: wait_on_dquot fs/quota/dquot.c:354 [inline] ffff888053f195a8 (&dquot->dq_lock){+.+.}-{4:4}, at: dqget+0x72a/0xf10 fs/quota/dquot.c:972 but task is already holding lock: ffff8880504b7388 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x855/0x1bc0 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}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524 ext4_setattr+0x855/0x1bc0 fs/ext4/inode.c:5816 notify_change+0xb36/0xe40 fs/attr.c:552 chown_common+0x40c/0x5c0 fs/open.c:790 do_fchownat+0x161/0x270 fs/open.c:821 __do_sys_chown fs/open.c:841 [inline] __se_sys_chown fs/open.c:839 [inline] __x64_sys_chown+0x82/0xa0 fs/open.c:839 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (jbd2_handle){++++}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 start_this_handle+0x1fa7/0x21c0 fs/jbd2/transaction.c:444 jbd2__journal_start+0x2c1/0x5b0 fs/jbd2/transaction.c:501 jbd2_journal_start+0x2a/0x40 fs/jbd2/transaction.c:540 ocfs2_start_trans+0x376/0x6d0 fs/ocfs2/journal.c:374 ocfs2_shutdown_local_alloc+0x200/0xa10 fs/ocfs2/localalloc.c:417 ocfs2_dismount_volume+0x201/0x8d0 fs/ocfs2/super.c:1825 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1755 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&journal->j_trans_barrier){.+.+}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524 ocfs2_start_trans+0x36a/0x6d0 fs/ocfs2/journal.c:372 ocfs2_shutdown_local_alloc+0x200/0xa10 fs/ocfs2/localalloc.c:417 ocfs2_dismount_volume+0x201/0x8d0 fs/ocfs2/super.c:1825 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1755 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (sb_internal#2){.+.+}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 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:1795 [inline] sb_start_intwrite include/linux/fs.h:1978 [inline] ocfs2_start_trans+0x26b/0x6d0 fs/ocfs2/journal.c:370 ocfs2_acquire_dquot+0x455/0xb30 fs/ocfs2/quota_global.c:860 dqget+0x7b1/0xf10 fs/quota/dquot.c:977 dquot_set_dqblk+0x2b/0xfa0 fs/quota/dquot.c:2820 quota_setquota+0x4b7/0x540 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:961 [inline] __se_sys_quotactl+0x279/0x950 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_create_local_dquot+0x19d/0x1a40 fs/ocfs2/quota_local.c:1227 ocfs2_acquire_dquot+0x80f/0xb30 fs/ocfs2/quota_global.c:883 dqget+0x7b1/0xf10 fs/quota/dquot.c:977 dquot_set_dqblk+0x2b/0xfa0 fs/quota/dquot.c:2820 quota_setquota+0x4b7/0x540 fs/quota/quota.c:310 __do_sys_quotactl fs/quota/quota.c:961 [inline] __se_sys_quotactl+0x279/0x950 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #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+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 wait_on_dquot fs/quota/dquot.c:354 [inline] dqget+0x72a/0xf10 fs/quota/dquot.c:972 dquot_transfer+0x2f8/0x6d0 fs/quota/dquot.c:2140 ext4_setattr+0x865/0x1bc0 fs/ext4/inode.c:5817 notify_change+0xb36/0xe40 fs/attr.c:552 chown_common+0x40c/0x5c0 fs/open.c:790 do_fchownat+0x161/0x270 fs/open.c:821 __do_sys_fchownat fs/open.c:836 [inline] __se_sys_fchownat fs/open.c:833 [inline] __x64_sys_fchownat+0xb5/0xd0 fs/open.c:833 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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.1.12594/15813: #0: ffff888055684428 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff8880504b76a0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_killable include/linux/fs.h:874 [inline] #1: ffff8880504b76a0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: chown_common+0x313/0x5c0 fs/open.c:778 #2: ffff8880504b7388 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x855/0x1bc0 fs/ext4/inode.c:5816 stack backtrace: CPU: 1 UID: 0 PID: 15813 Comm: syz.1.12594 Not tainted 6.16.0-rc2-syzkaller-00378-gb67ec639010f #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 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+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 wait_on_dquot fs/quota/dquot.c:354 [inline] dqget+0x72a/0xf10 fs/quota/dquot.c:972 dquot_transfer+0x2f8/0x6d0 fs/quota/dquot.c:2140 ext4_setattr+0x865/0x1bc0 fs/ext4/inode.c:5817 notify_change+0xb36/0xe40 fs/attr.c:552 chown_common+0x40c/0x5c0 fs/open.c:790 do_fchownat+0x161/0x270 fs/open.c:821 __do_sys_fchownat fs/open.c:836 [inline] __se_sys_fchownat fs/open.c:833 [inline] __x64_sys_fchownat+0xb5/0xd0 fs/open.c:833 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3a8fb8e929 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:00007f3a90a0c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000104 RAX: ffffffffffffffda RBX: 00007f3a8fdb5fa0 RCX: 00007f3a8fb8e929 RDX: 000000000000ee00 RSI: 0000200000000200 RDI: 0000000000000004 RBP: 00007f3a8fc10b39 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3a8fdb5fa0 R15: 00007ffd8af9a048