====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.6.179/7682 is trying to acquire lock: ffff0000d4df81d0 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0x9c/0x124 mm/memory.c:6957 but task is already holding lock: ffff0000c1616a20 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_fiemap+0x26c/0x9c4 fs/ocfs2/extent_map.c:765 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1590 ocfs2_lock_global_qf+0x1a8/0x22c fs/ocfs2/quota_global.c:314 ocfs2_acquire_dquot+0x258/0xa10 fs/ocfs2/quota_global.c:828 dqget+0x654/0xccc fs/quota/dquot.c:977 __dquot_initialize+0x2d4/0xa80 fs/quota/dquot.c:1505 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1567 ocfs2_get_init_inode+0x134/0x1a8 fs/ocfs2/namei.c:205 ocfs2_symlink+0x66c/0x1ff8 fs/ocfs2/namei.c:1890 vfs_symlink+0x138/0x288 fs/namei.c:4730 do_symlinkat+0x17c/0x360 fs/namei.c:4756 __do_sys_symlinkat fs/namei.c:4772 [inline] __se_sys_symlinkat fs/namei.c:4769 [inline] __arm64_sys_symlinkat+0x9c/0xb4 fs/namei.c:4769 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #4 (&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]){+.+.}-{4:4}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1590 inode_lock include/linux/fs.h:869 [inline] ocfs2_lock_global_qf+0x18c/0x22c fs/ocfs2/quota_global.c:313 ocfs2_acquire_dquot+0x258/0xa10 fs/ocfs2/quota_global.c:828 dqget+0x654/0xccc fs/quota/dquot.c:977 __dquot_initialize+0x2d4/0xa80 fs/quota/dquot.c:1505 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1567 ocfs2_get_init_inode+0x134/0x1a8 fs/ocfs2/namei.c:205 ocfs2_symlink+0x66c/0x1ff8 fs/ocfs2/namei.c:1890 vfs_symlink+0x138/0x288 fs/namei.c:4730 do_symlinkat+0x17c/0x360 fs/namei.c:4756 __do_sys_symlinkat fs/namei.c:4772 [inline] __se_sys_symlinkat fs/namei.c:4769 [inline] __arm64_sys_symlinkat+0x9c/0xb4 fs/namei.c:4769 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #3 (&dquot->dq_lock){+.+.}-{4:4}: __mutex_lock_common+0x1d0/0x2678 kernel/locking/mutex.c:598 __mutex_lock kernel/locking/mutex.c:760 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812 dquot_release+0x5c/0x4d4 fs/quota/dquot.c:531 ext4_release_dquot+0x3fc/0x6d0 fs/ext4/super.c:-1 quota_release_workfn+0x370/0x614 fs/quota/dquot.c:840 process_one_work+0x7e8/0x155c kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3400 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 -> #2 (sb_internal){++++}-{0:0}: percpu_down_write+0x6c/0x2f0 kernel/locking/percpu-rwsem.c:232 sb_wait_write fs/super.c:1911 [inline] freeze_super+0x6a4/0xe00 fs/super.c:2194 fs_bdev_freeze+0x19c/0x304 fs/super.c:1540 bdev_freeze+0xc8/0x250 block/bdev.c:298 ext4_force_shutdown+0x2b8/0x5c4 fs/ext4/ioctl.c:822 ext4_ioctl_shutdown fs/ext4/ioctl.c:857 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x1a20/0x309c fs/ext4/ioctl.c:1626 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:584 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #1 (sb_pagefaults){++++}-{0:0}: percpu_down_read_internal+0x5c/0x298 include/linux/percpu-rwsem.h:53 percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1798 [inline] sb_start_pagefault include/linux/fs.h:1963 [inline] ext4_page_mkwrite+0x198/0xea8 fs/ext4/inode.c:6703 do_page_mkwrite+0x138/0x2b8 mm/memory.c:3361 do_shared_fault mm/memory.c:5649 [inline] do_fault mm/memory.c:5711 [inline] do_pte_missing mm/memory.c:4234 [inline] handle_pte_fault mm/memory.c:6052 [inline] __handle_mm_fault mm/memory.c:6195 [inline] handle_mm_fault+0x1a94/0x4d34 mm/memory.c:6364 do_page_fault+0x57c/0x13cc arch/arm64/mm/fault.c:696 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:789 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:929 el0_da+0x64/0x164 arch/arm64/kernel/entry-common.c:697 el0t_64_sync_handler+0x90/0x12c arch/arm64/kernel/entry-common.c:901 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #0 (&mm->mmap_lock){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __might_fault+0xc4/0x124 mm/memory.c:6958 _inline_copy_to_user include/linux/uaccess.h:192 [inline] copy_to_user include/linux/uaccess.h:223 [inline] fiemap_fill_next_extent+0x17c/0x3f0 fs/ioctl.c:145 ocfs2_fiemap+0x648/0x9c4 fs/ocfs2/extent_map.c:806 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1140/0x1834 fs/ioctl.c:532 __do_sys_ioctl fs/ioctl.c:596 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __arm64_sys_ioctl+0xe4/0x1c4 fs/ioctl.c:584 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 other info that might help us debug this: Chain exists of: &mm->mmap_lock --> &ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE] --> &ocfs2_quota_ip_alloc_sem_key Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&ocfs2_quota_ip_alloc_sem_key); lock(&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]); lock(&ocfs2_quota_ip_alloc_sem_key); rlock(&mm->mmap_lock); *** DEADLOCK *** 1 lock held by syz.6.179/7682: #0: ffff0000c1616a20 (&ocfs2_quota_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_fiemap+0x26c/0x9c4 fs/ocfs2/extent_map.c:765 stack backtrace: CPU: 1 UID: 0 PID: 7682 Comm: syz.6.179 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (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:2043 check_noncircular+0x154/0x174 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5237 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868 __might_fault+0xc4/0x124 mm/memory.c:6958 _inline_copy_to_user include/linux/uaccess.h:192 [inline] copy_to_user include/linux/uaccess.h:223 [inline] fiemap_fill_next_extent+0x17c/0x3f0 fs/ioctl.c:145 ocfs2_fiemap+0x648/0x9c4 fs/ocfs2/extent_map.c:806 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1140/0x1834 fs/ioctl.c:532 __do_sys_ioctl fs/ioctl.c:596 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __arm64_sys_ioctl+0xe4/0x1c4 fs/ioctl.c:584 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596