====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.1080/9319 is trying to acquire lock: ffff88807b4e00b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 but task is already holding lock: ffff88807775a7f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xdb/0x1220 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){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_extend_file+0xdb/0x1220 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+0x162/0x1e0 fs/hfs/extent.c:144 hfs_write_inode+0x92/0x7d0 fs/hfs/inode.c:434 write_inode fs/fs-writeback.c:1473 [inline] __writeback_single_inode+0x705/0xee0 fs/fs-writeback.c:1690 writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1916 wb_writeback+0x450/0xba0 fs/fs-writeback.c:2095 wb_do_writeback fs/fs-writeback.c:2242 [inline] wb_workfn+0x3ff/0xe20 fs/fs-writeback.c:2282 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 -> #0 (&tree->tree_lock/1){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ef/0x1220 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b4/0x620 fs/hfs/catalog.c:104 hfs_create+0x66/0xd0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3488 [inline] open_last_lookups fs/namei.c:3556 [inline] path_openat+0x1277/0x3190 fs/namei.c:3786 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock/1); *** DEADLOCK *** 4 locks held by syz.1.1080/9319: #0: ffff88805507a418 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403 #1: ffff88807775a338 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff88807775a338 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: open_last_lookups fs/namei.c:3553 [inline] #1: ffff88807775a338 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3786 #2: ffff88807e9b20b0 (&tree->tree_lock){+.+.}-{3:3}, at: hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 #3: ffff88807775a7f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xdb/0x1220 fs/hfs/extent.c:397 stack backtrace: CPU: 1 PID: 9319 Comm: syz.1.1080 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_find_init+0x17e/0x1f0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ef/0x1220 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b4/0x620 fs/hfs/catalog.c:104 hfs_create+0x66/0xd0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3488 [inline] open_last_lookups fs/namei.c:3556 [inline] path_openat+0x1277/0x3190 fs/namei.c:3786 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4b8a18eec9 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:00007f4b8b064038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4b8a3e5fa0 RCX: 00007f4b8a18eec9 RDX: 0000000000141042 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f4b8a211f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4b8a3e6038 R14: 00007f4b8a3e5fa0 R15: 00007ffc3f0e0c48