loop0: detected capacity change from 0 to 1024
hfsplus: trying to free free bnode 0(1)
============================================
WARNING: possible recursive locking detected
5.15.178-syzkaller #0 Not tainted
--------------------------------------------
syz-executor177/4164 is trying to acquire lock:
ffff888025089548 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_get_block+0x37f/0x14e0 fs/hfsplus/extents.c:260

but task is already holding lock:
ffff88802508a988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x30f/0xc70 fs/hfsplus/extents.c:577

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&HFSPLUS_I(inode)->extents_lock);
  lock(&HFSPLUS_I(inode)->extents_lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

6 locks held by syz-executor177/4164:
 #0: ffff888077a3e460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff888025089e00 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
 #1: ffff888025089e00 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_unlinkat+0x266/0x950 fs/namei.c:4331
 #2: ffff88802508ab80 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #2: ffff88802508ab80 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4269
 #3: ffff88802433a998 (&sbi->vh_mutex){+.+.}-{3:3}, at: hfsplus_unlink+0x15d/0x7f0 fs/hfsplus/dir.c:370
 #4: ffff88802508a988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_truncate+0x30f/0xc70 fs/hfsplus/extents.c:577
 #5: ffff88802433a8f8 (&sbi->alloc_mutex){+.+.}-{3:3}, at: hfsplus_block_free+0xb7/0x4f0 fs/hfsplus/bitmap.c:182

stack backtrace:
CPU: 1 PID: 4164 Comm: syz-executor177 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2946 [inline]
 check_deadlock kernel/locking/lockdep.c:2989 [inline]
 validate_chain+0x46d2/0x5930 kernel/locking/lockdep.c:3775
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfsplus_get_block+0x37f/0x14e0 fs/hfsplus/extents.c:260
 block_read_full_page+0x2f9/0xde0 fs/buffer.c:2290
 do_read_cache_page+0x752/0x1040
 read_mapping_page include/linux/pagemap.h:515 [inline]
 hfsplus_block_free+0x120/0x4f0 fs/hfsplus/bitmap.c:185
 hfsplus_free_extents+0x17a/0xae0 fs/hfsplus/extents.c:363
 hfsplus_file_truncate+0x871/0xc70 fs/hfsplus/extents.c:592
 hfsplus_delete_inode+0x170/0x220
 hfsplus_unlink+0x50d/0x7f0 fs/hfsplus/dir.c:405
 vfs_unlink+0x359/0x5f0 fs/namei.c:4280
 do_unlinkat+0x4a3/0x950 fs/namei.c:4348
 __do_sys_unlink fs/namei.c:4396 [inline]
 __se_sys_unlink fs/namei.c:4394 [inline]
 __x64_sys_unlink+0x45/0x50 fs/namei.c:4394
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdac0f67af9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffef4446c18 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fdac0fb005e RCX: 00007fdac0f67af9
RDX: 00007fdac0f66df0 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fdac0fb0066 R08: 0000000000000669 R09: 0000000000000000
R10: 00007ffef4446ae0 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffef4446df8 R14: 0000000000000001 R15: 0000000000000001
 </TASK>