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) UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 ============================================ WARNING: possible recursive locking detected 6.15.0-syzkaller-11173-g546b1c9e93c2 #0 Not tainted -------------------------------------------- syz.0.0/5328 is trying to acquire lock: ffff888011a8ad28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_free_blocks fs/udf/balloc.c:375 [inline] ffff888011a8ad28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_free_blocks+0x9e2/0x17f0 fs/udf/balloc.c:677 but task is already holding lock: ffff888011a8ad28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:581 [inline] ffff888011a8ad28 (&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 4 locks held by syz.0.0/5328: #0: ffff888011e2c428 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1157 #1: ffff888043b7cf60 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888043b7cf60 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: udf_file_write_iter+0x6e/0x6c0 fs/udf/file.c:95 #2: ffff888043b7cd90 (&ei->i_data_sem#2){++++}-{4:4}, at: udf_map_block+0x291/0x42a0 fs/udf/inode.c:439 #3: ffff888011a8ad28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:581 [inline] #3: ffff888011a8ad28 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_new_block+0xfab/0x1ba0 fs/udf/balloc.c:725 stack backtrace: CPU: 0 UID: 0 PID: 5328 Comm: syz.0.0 Not tainted 6.15.0-syzkaller-11173-g546b1c9e93c2 #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: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3044 check_deadlock kernel/locking/lockdep.c:3096 [inline] validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3898 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 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 udf_add_aext fs/udf/inode.c:2127 [inline] udf_insert_aext fs/udf/inode.c:2317 [inline] udf_update_extents fs/udf/inode.c:1205 [inline] inode_getblk fs/udf/inode.c:919 [inline] udf_map_block+0x32fd/0x42a0 fs/udf/inode.c:447 __udf_get_block+0x52/0x250 fs/udf/inode.c:461 get_more_blocks fs/direct-io.c:648 [inline] do_direct_IO fs/direct-io.c:936 [inline] __blockdev_direct_IO+0x16da/0x33d0 fs/direct-io.c:1243 blockdev_direct_IO include/linux/fs.h:3473 [inline] udf_direct_IO+0x139/0x200 fs/udf/inode.c:305 generic_file_direct_write+0x1db/0x3e0 mm/filemap.c:4046 __generic_file_write_iter+0x11d/0x230 mm/filemap.c:4215 udf_file_write_iter+0x2d5/0x6c0 fs/udf/file.c:111 iter_file_splice_write+0x937/0x1000 fs/splice.c:738 do_splice_from fs/splice.c:935 [inline] direct_splice_actor+0xfe/0x160 fs/splice.c:1158 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1102 do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1227 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1745d8e969 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:00007f1746b51038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f1745fb5fa0 RCX: 00007f1745d8e969 RDX: 0000000000000000 RSI: 000000000000000b RDI: 000000000000000a RBP: 00007f1745e10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000fffe82 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1745fb5fa0 R15: 00007ffdbffab458