syzbot

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WARNING: the mand mount option is being deprecated and
         will be removed in v5.15!
======================================================
============================================
WARNING: possible recursive locking detected
4.19.211-syzkaller #0 Not tainted
--------------------------------------------
syz-executor237/8096 is trying to acquire lock:
00000000c332e86b (&HFSPLUS_I(inode)->extents_lock){+.+.}, at: hfsplus_file_extend+0x1bb/0xf40 fs/hfsplus/extents.c:457

but task is already holding lock:
0000000086464514 (&HFSPLUS_I(inode)->extents_lock){+.+.}, at: hfsplus_file_extend+0x1bb/0xf40 fs/hfsplus/extents.c:457

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

4 locks held by syz-executor237/8096:
 #0: 00000000bbc7cafe (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000bbc7cafe (sb_writers#11){.+.+}, at: do_sys_ftruncate+0x297/0x560 fs/open.c:189
 #1: 00000000ff4bafdd (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline]
 #1: 00000000ff4bafdd (&sb->s_type->i_mutex_key#17){+.+.}, at: do_truncate+0x125/0x1f0 fs/open.c:61
 #2: 0000000086464514 (&HFSPLUS_I(inode)->extents_lock){+.+.}, at: hfsplus_file_extend+0x1bb/0xf40 fs/hfsplus/extents.c:457
 #3: 00000000f5e68561 (&tree->tree_lock/1){+.+.}, at: hfsplus_find_init+0x170/0x220 fs/hfsplus/bfind.c:33

stack backtrace:
CPU: 0 PID: 8096 Comm: syz-executor237 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:1764 [inline]
 check_deadlock kernel/locking/lockdep.c:1808 [inline]
 validate_chain kernel/locking/lockdep.c:2404 [inline]
 __lock_acquire.cold+0x121/0x57e kernel/locking/lockdep.c:3416
 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908
 __mutex_lock_common kernel/locking/mutex.c:937 [inline]
 __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078
 hfsplus_file_extend+0x1bb/0xf40 fs/hfsplus/extents.c:457
 hfsplus_bmap_reserve+0x298/0x440 fs/hfsplus/btree.c:357
 __hfsplus_ext_write_extent+0x45b/0x5a0 fs/hfsplus/extents.c:104
 __hfsplus_ext_cache_extent fs/hfsplus/extents.c:186 [inline]
 hfsplus_ext_read_extent+0x910/0xab0 fs/hfsplus/extents.c:218
 hfsplus_file_extend+0x672/0xf40 fs/hfsplus/extents.c:461
 hfsplus_get_block+0x196/0x960 fs/hfsplus/extents.c:245
 __block_write_begin_int+0x46c/0x17b0 fs/buffer.c:1978
 __block_write_begin fs/buffer.c:2028 [inline]
 block_write_begin+0x58/0x2e0 fs/buffer.c:2087
 cont_write_begin+0x55a/0x820 fs/buffer.c:2440
 hfsplus_write_begin+0x87/0x150 fs/hfsplus/inode.c:52
 cont_expand_zero fs/buffer.c:2367 [inline]
 cont_write_begin+0x2ee/0x820 fs/buffer.c:2430
 hfsplus_write_begin+0x87/0x150 fs/hfsplus/inode.c:52
 generic_cont_expand_simple+0x106/0x170 fs/buffer.c:2331
 hfsplus_setattr+0x18b/0x310 fs/hfsplus/inode.c:257
 notify_change+0x70b/0xfc0 fs/attr.c:334
 do_truncate+0x134/0x1f0 fs/open.c:63
 do_sys_ftruncate+0x492/0x560 fs/open.c:194
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f159ab94799
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff6d5329f8 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f159ab94799
RDX: 0000000000000000 RSI: 0000000002007ffb RDI: 0000000000000004