====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.3694/20191 is trying to acquire lock: ffff888027a840b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 but task is already holding lock: ffff888027a41af8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 hfs_ext_write_extent+0x161/0x1e0 fs/hfs/extent.c:144 hfs_write_inode+0x91/0x7d0 fs/hfs/inode.c:429 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976 wb_writeback+0x43b/0xaf0 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x409/0xef0 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (&tree->tree_lock#2/1){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x14f4/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); *** DEADLOCK *** 4 locks held by syz.1.3694/20191: #0: ffff88805137e428 (sb_writers#29){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff888027a42320 (&type->i_mutex_dir_key#18){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #1: ffff888027a42320 (&type->i_mutex_dir_key#18){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3804 [inline] #1: ffff888027a42320 (&type->i_mutex_dir_key#18){+.+.}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4043 #2: ffff8880582760b0 (&tree->tree_lock#2){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 #3: ffff888027a41af8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 stack backtrace: CPU: 1 UID: 0 PID: 20191 Comm: syz.1.3694 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 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+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x14f4/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: 0033:0x7f803998ebe9 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:00007f803a849038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8039bc6180 RCX: 00007f803998ebe9 RDX: 0000000000101442 RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007f8039a11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8039bc6218 R14: 00007f8039bc6180 R15: 00007fff3f1e8a78