============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.1.1119/10980 is trying to acquire lock: ffff8880329ae0b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 but task is already holding lock: ffff8880329ae0b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&tree->tree_lock/1); lock(&tree->tree_lock/1); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.1.1119/10980: #0: ffff888029260420 (sb_writers#36){.+.+}-{0:0}, at: class_super_write_constructor include/linux/fs/super.h:128 [inline] #0: ffff888029260420 (sb_writers#36){.+.+}-{0:0}, at: do_ftruncate+0x446/0x560 fs/open.c:194 #1: ffff888077c43d20 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1056 [inline] #1: ffff888077c43d20 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63 #2: ffff888077c43b78 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1540 fs/hfs/extent.c:397 #3: ffff8880329ae0b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 #4: ffff888077c427f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1540 fs/hfs/extent.c:397 stack backtrace: CPU: 1 UID: 0 PID: 10980 Comm: syz.1.1119 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3895 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2f6/0x1540 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x31e/0x1540 fs/hfs/extent.c:401 hfs_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145 block_write_begin fs/buffer.c:2256 [inline] cont_write_begin+0x78c/0xb50 fs/buffer.c:2594 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52 cont_expand_zero fs/buffer.c:2522 [inline] cont_write_begin+0x2fd/0xb50 fs/buffer.c:2584 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52 hfs_file_truncate+0x19c/0xb30 fs/hfs/extent.c:495 hfs_inode_setattr+0x4a9/0x670 fs/hfs/inode.c:665 notify_change+0xc1a/0xf40 fs/attr.c:546 do_truncate+0x1a4/0x220 fs/open.c:68 do_ftruncate+0x4a5/0x560 fs/open.c:195 do_sys_ftruncate fs/open.c:207 [inline] __do_sys_ftruncate fs/open.c:212 [inline] __se_sys_ftruncate fs/open.c:210 [inline] __x64_sys_ftruncate+0x92/0xf0 fs/open.c:210 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fce3a18f6c9 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:00007fce3afd2038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007fce3a3e5fa0 RCX: 00007fce3a18f6c9 RDX: 0000000000000000 RSI: 0000000002007ffc RDI: 0000000000000005 RBP: 00007fce3a211f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fce3a3e6038 R14: 00007fce3a3e5fa0 R15: 00007ffdfd7049e8