loop3: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.3.908/12150 is trying to acquire lock: ffff888063103b18 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397 but task is already holding lock: ffff88805e6aa0a0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&tree->tree_lock#2/1){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x35f/0x1680 fs/hfs/extent.c:401 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x221/0x810 fs/hfs/catalog.c:104 hfs_create+0x78/0xe0 fs/hfs/dir.c:196 lookup_open fs/namei.c:4508 [inline] open_last_lookups fs/namei.c:4608 [inline] path_openat+0x1344/0x3850 fs/namei.c:4856 do_file_open+0x23e/0x4a0 fs/namei.c:4888 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6e/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x3a0/0x1680 fs/hfs/extent.c:401 hfs_get_block+0x401/0xbe0 fs/hfs/extent.c:353 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2123 block_write_begin fs/buffer.c:2234 [inline] cont_write_begin+0x71b/0xac0 fs/buffer.c:2596 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:54 cont_expand_zero fs/buffer.c:2524 [inline] cont_write_begin+0x2d6/0xac0 fs/buffer.c:2586 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:54 hfs_file_truncate+0x1cf/0xb60 fs/hfs/extent.c:495 hfs_inode_setattr+0x49a/0x6c0 fs/hfs/inode.c:669 notify_change+0xbb8/0xec0 fs/attr.c:556 do_truncate+0x1c2/0x250 fs/open.c:68 do_ftruncate+0x4e0/0x590 fs/open.c:194 ksys_ftruncate fs/open.c:206 [inline] __do_sys_ftruncate fs/open.c:211 [inline] __se_sys_ftruncate fs/open.c:209 [inline] __x64_sys_ftruncate+0x8f/0xe0 fs/open.c:209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 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(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); *** DEADLOCK *** 4 locks held by syz.3.908/12150: #0: ffff888064d7c500 (sb_writers#37){.+.+}-{0:0}, at: class_super_write_constructor include/linux/fs/super.h:130 [inline] #0: ffff888064d7c500 (sb_writers#37){.+.+}-{0:0}, at: do_ftruncate+0x480/0x590 fs/open.c:193 #1: ffff888063105070 (&sb->s_type->i_mutex_key#46){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1029 [inline] #1: ffff888063105070 (&sb->s_type->i_mutex_key#46){+.+.}-{4:4}, at: do_truncate+0x18f/0x250 fs/open.c:63 #2: ffff888063104e98 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397 #3: ffff88805e6aa0a0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18d/0x300 fs/hfs/bfind.c:-1 stack backtrace: CPU: 1 UID: 0 PID: 12150 Comm: syz.3.908 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfs_extend_file+0xf9/0x1680 fs/hfs/extent.c:397 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6e/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x3a0/0x1680 fs/hfs/extent.c:401 hfs_get_block+0x401/0xbe0 fs/hfs/extent.c:353 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2123 block_write_begin fs/buffer.c:2234 [inline] cont_write_begin+0x71b/0xac0 fs/buffer.c:2596 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:54 cont_expand_zero fs/buffer.c:2524 [inline] cont_write_begin+0x2d6/0xac0 fs/buffer.c:2586 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:54 hfs_file_truncate+0x1cf/0xb60 fs/hfs/extent.c:495 hfs_inode_setattr+0x49a/0x6c0 fs/hfs/inode.c:669 notify_change+0xbb8/0xec0 fs/attr.c:556 do_truncate+0x1c2/0x250 fs/open.c:68 do_ftruncate+0x4e0/0x590 fs/open.c:194 ksys_ftruncate fs/open.c:206 [inline] __do_sys_ftruncate fs/open.c:211 [inline] __se_sys_ftruncate fs/open.c:209 [inline] __x64_sys_ftruncate+0x8f/0xe0 fs/open.c:209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f826a92ce59 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:00007f8268b7e028 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007f826aba5fa0 RCX: 00007f826a92ce59 RDX: 0000000000000000 RSI: 0000000002007ffc RDI: 0000000000000004 RBP: 00007f826a9c2e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f826aba6038 R14: 00007f826aba5fa0 R15: 00007ffdabf98e38