loop0: detected capacity change from 0 to 2048
UDF-fs: error (device loop0): udf_read_tagged: read failed, block=2362, location=2362
UDF-fs: error (device loop0): udf_read_tagged: tag checksum failed, block 99: 0x27 != 0x4d
UDF-fs: error (device loop0): udf_read_tagged: tag checksum failed, block 160: 0xd2 != 0xd4
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
overlay: ./bus is not a directory
============================================
WARNING: possible recursive locking detected
6.15.0-rc3-syzkaller-00244-gc3137514f1f1 #0 Not tainted
--------------------------------------------
syz.0.0/5348 is trying to acquire lock:
ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_free_blocks fs/udf/balloc.c:375 [inline]
ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_free_blocks+0x9e2/0x17f0 fs/udf/balloc.c:677

but task is already holding lock:
ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:581 [inline]
ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_new_block+0xfab/0x1ba0 fs/udf/balloc.c:725

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

       CPU0
       ----
  lock(&sbi->s_alloc_mutex);
  lock(&sbi->s_alloc_mutex);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz.0.0/5348:
 #0: ffff88803fe66b78 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1213
 #1: ffff88801abfa420 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
 #1: ffff88801abfa420 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680
 #2: ffff888044525c20 (&sb->s_type->i_mutex_key#19){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #2: ffff888044525c20 (&sb->s_type->i_mutex_key#19){+.+.}-{4:4}, at: udf_file_write_iter+0x6e/0x6c0 fs/udf/file.c:95
 #3: ffff888044525a50 (&ei->i_data_sem#2){++++}-{4:4}, at: udf_map_block+0x291/0x42a0 fs/udf/inode.c:439
 #4: ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:581 [inline]
 #4: ffff88803f949d28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_new_block+0xfab/0x1ba0 fs/udf/balloc.c:725

stack backtrace:
CPU: 0 UID: 0 PID: 5348 Comm: syz.0.0 Not tainted 6.15.0-rc3-syzkaller-00244-gc3137514f1f1 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3042
 check_deadlock kernel/locking/lockdep.c:3094 [inline]
 validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3896
 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
 __mutex_lock_common kernel/locking/mutex.c:601 [inline]
 __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746
 udf_table_free_blocks fs/udf/balloc.c:375 [inline]
 udf_free_blocks+0x9e2/0x17f0 fs/udf/balloc.c:677
 udf_delete_aext+0x4df/0xbc0 fs/udf/inode.c:2373
 udf_table_new_block fs/udf/balloc.c:645 [inline]
 udf_new_block+0x1404/0x1ba0 fs/udf/balloc.c:725
 inode_getblk fs/udf/inode.c:895 [inline]
 udf_map_block+0x12b1/0x42a0 fs/udf/inode.c:447
 __udf_get_block+0x52/0x250 fs/udf/inode.c:461
 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2116
 block_write_begin+0x8a/0x120 fs/buffer.c:2227
 udf_write_begin+0x100/0x260 fs/udf/inode.c:256
 generic_perform_write+0x2c4/0x910 mm/filemap.c:4103
 udf_file_write_iter+0x2d5/0x6c0 fs/udf/file.c:111
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x548/0xa90 fs/read_write.c:684
 ksys_write+0x145/0x250 fs/read_write.c:736
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fecfd58e969
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:00007fecfe350038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fecfd7b5fa0 RCX: 00007fecfd58e969
RDX: 000000000208e24b RSI: 0000200000000240 RDI: 0000000000000009
RBP: 00007fecfd610ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fecfd7b5fa0 R15: 00007ffcc9b50318
 </TASK>