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)
============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.0.0/5349 is trying to acquire lock:
ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_free_blocks fs/udf/balloc.c:375 [inline]
ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_free_blocks+0xa8f/0x18e0 fs/udf/balloc.c:677

but task is already holding lock:
ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_prealloc_blocks fs/udf/balloc.c:516 [inline]
ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_prealloc_blocks+0x8d0/0x10f0 fs/udf/balloc.c:701

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

4 locks held by syz.0.0/5349:
 #0: ffff888041382420 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
 #0: ffff888041382420 (sb_writers#12){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
 #1: ffff88804732cf40 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #1: ffff88804732cf40 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: udf_file_write_iter+0x6e/0x6c0 fs/udf/file.c:95
 #2: ffff88804732cd70 (&ei->i_data_sem#2){++++}-{4:4}, at: udf_map_block+0x283/0x45f0 fs/udf/inode.c:446
 #3: ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_prealloc_blocks fs/udf/balloc.c:516 [inline]
 #3: ffff888036ff4128 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_prealloc_blocks+0x8d0/0x10f0 fs/udf/balloc.c:701

stack backtrace:
CPU: 0 UID: 0 PID: 5349 Comm: syz.0.0 Not tainted syzkaller #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+0xe8/0x150 lib/dump_stack.c:120
 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
 check_deadlock kernel/locking/lockdep.c:3093 [inline]
 validate_chain kernel/locking/lockdep.c:3895 [inline]
 __lock_acquire+0x2540/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
 __mutex_lock_common kernel/locking/mutex.c:614 [inline]
 __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
 udf_table_free_blocks fs/udf/balloc.c:375 [inline]
 udf_free_blocks+0xa8f/0x18e0 fs/udf/balloc.c:677
 udf_delete_aext+0x4df/0xbc0 fs/udf/inode.c:2383
 udf_table_prealloc_blocks fs/udf/balloc.c:543 [inline]
 udf_prealloc_blocks+0xbb4/0x10f0 fs/udf/balloc.c:701
 udf_prealloc_extents fs/udf/inode.c:1060 [inline]
 inode_getblk fs/udf/inode.c:918 [inline]
 udf_map_block+0x1f70/0x45f0 fs/udf/inode.c:454
 __udf_get_block+0x52/0x250 fs/udf/inode.c:468
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin+0x8d/0x120 fs/buffer.c:2256
 udf_write_begin+0x118/0x270 fs/udf/inode.c:262
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
 udf_file_write_iter+0x2d5/0x6c0 fs/udf/file.c:111
 do_iter_readv_writev+0x623/0x8c0 fs/read_write.c:-1
 vfs_writev+0x31a/0x960 fs/read_write.c:1057
 do_pwritev fs/read_write.c:1153 [inline]
 __do_sys_pwritev2 fs/read_write.c:1211 [inline]
 __se_sys_pwritev2+0x179/0x290 fs/read_write.c:1202
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd34cd8f7c9
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:00007fd34db8b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007fd34cfe5fa0 RCX: 00007fd34cd8f7c9
RDX: 0000000000000001 RSI: 00002000000001c0 RDI: 000000000000000d
RBP: 00007fd34ce13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7b R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd34cfe6038 R14: 00007fd34cfe5fa0 R15: 00007ffc33ed2018
 </TASK>