====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.8.277/7884 is trying to acquire lock: ffff888032f320a0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 but task is already holding lock: ffff88803af40128 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf2/0x15e0 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}: __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfs_extend_file+0xf2/0x15e0 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+0x17e/0x210 fs/hfs/extent.c:144 hfs_write_inode+0x117/0x960 fs/hfs/inode.c:459 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x75d/0x11a0 fs/fs-writeback.c:1813 writeback_sb_inodes+0x995/0x19d0 fs/fs-writeback.c:2042 wb_writeback+0x456/0xb70 fs/fs-writeback.c:2227 wb_do_writeback fs/fs-writeback.c:2374 [inline] wb_workfn+0x41a/0xf60 fs/fs-writeback.c:2414 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (&tree->tree_lock/1){+.+.}-{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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x35c/0x15e0 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_move+0x216/0xbd0 fs/hfs/catalog.c:433 hfs_rename+0x111/0x1d0 fs/hfs/dir.c:306 vfs_rename+0xa96/0xeb0 fs/namei.c:6026 filename_renameat2+0x539/0x9c0 fs/namei.c:6144 __do_sys_rename fs/namei.c:6188 [inline] __se_sys_rename+0x55/0x2c0 fs/namei.c:6184 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 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/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock/1); *** DEADLOCK *** 4 locks held by syz.8.277/7884: #0: ffff88803cfe0480 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880610f1180 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff8880610f1180 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3756 [inline] #1: ffff8880610f1180 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3852 #2: ffff888032f360a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 #3: ffff88803af40128 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397 stack backtrace: CPU: 0 UID: 0 PID: 7884 Comm: syz.8.277 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x35c/0x15e0 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_move+0x216/0xbd0 fs/hfs/catalog.c:433 hfs_rename+0x111/0x1d0 fs/hfs/dir.c:306 vfs_rename+0xa96/0xeb0 fs/namei.c:6026 filename_renameat2+0x539/0x9c0 fs/namei.c:6144 __do_sys_rename fs/namei.c:6188 [inline] __se_sys_rename+0x55/0x2c0 fs/namei.c:6184 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdc3813c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdc36396028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007fdc383b5fa0 RCX: 00007fdc3813c799 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000200000000000 RBP: 00007fdc381d2bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdc383b6038 R14: 00007fdc383b5fa0 R15: 00007ffc151a4188