loop8: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 Not tainted ------------------------------------------------------ syz.8.1496/21027 is trying to acquire lock: ffff88807cab00b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x165/0x1e0 fs/hfs/bfind.c:-1 but task is already holding lock: ffff888051c64ef8 (&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:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:234 __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+0x6ee/0xff0 fs/fs-writeback.c:1745 writeback_sb_inodes+0x6b5/0x1000 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:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfs_find_init+0x165/0x1e0 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:234 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 vfs_create+0x24b/0x400 fs/namei.c:3398 do_mknodat+0x3c6/0x4d0 fs/namei.c:4278 __do_sys_mknod fs/namei.c:4311 [inline] __se_sys_mknod fs/namei.c:4309 [inline] __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4309 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 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.8.1496/21027: #0: ffff88807e954420 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff888051c65720 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline] #1: ffff888051c65720 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132 #2: ffff88807b32e0b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x165/0x1e0 fs/hfs/bfind.c:-1 #3: ffff888051c64ef8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 stack backtrace: CPU: 0 UID: 0 PID: 21027 Comm: syz.8.1496 Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2079 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfs_find_init+0x165/0x1e0 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:234 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 vfs_create+0x24b/0x400 fs/namei.c:3398 do_mknodat+0x3c6/0x4d0 fs/namei.c:4278 __do_sys_mknod fs/namei.c:4311 [inline] __se_sys_mknod fs/namei.c:4309 [inline] __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4309 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fae4a18e969 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:00007fae4af78038 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 00007fae4a3b5fa0 RCX: 00007fae4a18e969 RDX: 0000000000000002 RSI: 0000000000008000 RDI: 0000200000000080 RBP: 00007fae4a210ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fae4a3b5fa0 R15: 00007ffe3e150288