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.0.0/5323 is trying to acquire lock: ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_free_blocks fs/udf/balloc.c:376 [inline] ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_free_blocks+0xa8c/0x1900 fs/udf/balloc.c:678 but task is already holding lock: ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:582 [inline] ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_new_block+0xfb7/0x1c00 fs/udf/balloc.c:726 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.0.0/5323: #0: ffff8880129a8450 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff88801320afc0 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff88801320afc0 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff88801320afc0 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff88801320afc0 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 #2: ffff88801320a738 (&ei->i_data_sem#3){++++}-{4:4}, at: udf_symlink+0x1a4/0x1590 fs/udf/namei.c:599 #3: ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_new_block fs/udf/balloc.c:582 [inline] #3: ffff88801289cd20 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_new_block+0xfb7/0x1c00 fs/udf/balloc.c:726 stack backtrace: CPU: 0 UID: 0 PID: 5323 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 04/01/2014 Call Trace: 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+0x24df/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821 udf_table_free_blocks fs/udf/balloc.c:376 [inline] udf_free_blocks+0xa8c/0x1900 fs/udf/balloc.c:678 udf_delete_aext+0x4f5/0xc00 fs/udf/inode.c:2381 udf_table_new_block fs/udf/balloc.c:646 [inline] udf_new_block+0x142f/0x1c00 fs/udf/balloc.c:726 udf_symlink+0x32e/0x1590 fs/udf/namei.c:608 vfs_symlink+0x18b/0x330 fs/namei.c:5660 filename_symlinkat+0x1cd/0x410 fs/namei.c:5685 __do_sys_symlinkat fs/namei.c:5705 [inline] __se_sys_symlinkat+0x4e/0x2b0 fs/namei.c:5700 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcb6779de59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcb686ddfe8 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 00007fcb67a25fa0 RCX: 00007fcb6779de59 RDX: 00002000000003c0 RSI: 000000000000000a RDI: 0000200000000240 RBP: 00007fcb67833e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcb67a26038 R14: 00007fcb67a25fa0 R15: 00007ffee2258a28