loop2: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.2264/11238 is trying to acquire lock: ffff8880332b80b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 but task is already holding lock: ffff888051fac1f8 (&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/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 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+0x75a/0x11a0 fs/fs-writeback.c:1813 writeback_sb_inodes+0x992/0x1a20 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+0x414/0xf50 fs/fs-writeback.c:2414 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 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#2/1){+.+.}-{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/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 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_create+0x20f/0x800 fs/hfs/catalog.c:104 hfs_mkdir+0x79/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x413/0x630 fs/namei.c:5233 filename_mkdirat+0x285/0x510 fs/namei.c:5266 __do_sys_mkdir fs/namei.c:5293 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5290 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#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); *** DEADLOCK *** 4 locks held by syz.2.2264/11238: #0: ffff8880332bc420 (sb_writers#32){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff888051fabd20 (&type->i_mutex_dir_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888051fabd20 (&type->i_mutex_dir_key#25/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888051fabd20 (&type->i_mutex_dir_key#25/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888051fabd20 (&type->i_mutex_dir_key#25/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4922 #2: ffff88807a8ae0b0 (&tree->tree_lock#2){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 #3: ffff888051fac1f8 (&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: 11238 Comm: syz.2.2264 Not tainted syzkaller #0 PREEMPT(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/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 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_create+0x20f/0x800 fs/hfs/catalog.c:104 hfs_mkdir+0x79/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x413/0x630 fs/namei.c:5233 filename_mkdirat+0x285/0x510 fs/namei.c:5266 __do_sys_mkdir fs/namei.c:5293 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5290 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: 0033:0x7f7542b9c629 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:00007f7543a39028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f7542e15fa0 RCX: 00007f7542b9c629 RDX: 0000000000000000 RSI: 0000000000000014 RDI: 0000200000000b00 RBP: 00007f7542c32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7542e16038 R14: 00007f7542e15fa0 R15: 00007ffe7b964b38