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) bridge0: port 3(syz_tun) entered blocking state bridge0: port 3(syz_tun) entered disabled state syz_tun: entered allmulticast mode syz_tun: entered promiscuous mode bridge0: port 3(syz_tun) entered blocking state bridge0: port 3(syz_tun) entered forwarding state capability: warning: `syz.0.0' uses 32-bit capabilities (legacy support in use) ============================================ WARNING: possible recursive locking detected 6.16.0-rc1-syzkaller #0 Not tainted -------------------------------------------- syz.0.0/5327 is trying to acquire lock: ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_free_blocks fs/udf/balloc.c:375 [inline] ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_free_blocks+0x9e2/0x17f0 fs/udf/balloc.c:677 but task is already holding lock: ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_prealloc_blocks fs/udf/balloc.c:516 [inline] ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_prealloc_blocks+0x8d0/0x10b0 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.0.0/5327: #0: ffff88801ef2a428 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3092 [inline] #0: ffff88801ef2a428 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682 #1: ffff888043ff0f60 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888043ff0f60 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: udf_file_write_iter+0x6e/0x6c0 fs/udf/file.c:95 #2: ffff888043ff0d90 (&ei->i_data_sem#2){++++}-{4:4}, at: udf_map_block+0x291/0x42a0 fs/udf/inode.c:439 #3: ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_table_prealloc_blocks fs/udf/balloc.c:516 [inline] #3: ffff888011c78528 (&sbi->s_alloc_mutex){+.+.}-{4:4}, at: udf_prealloc_blocks+0x8d0/0x10b0 fs/udf/balloc.c:701 stack backtrace: CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.16.0-rc1-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: 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_prealloc_blocks fs/udf/balloc.c:543 [inline] udf_prealloc_blocks+0xb7e/0x10b0 fs/udf/balloc.c:701 udf_prealloc_extents fs/udf/inode.c:1053 [inline] inode_getblk fs/udf/inode.c:911 [inline] udf_map_block+0x1ddd/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:2151 block_write_begin+0x8a/0x120 fs/buffer.c:2262 udf_write_begin+0x100/0x260 fs/udf/inode.c:256 generic_perform_write+0x2c4/0x910 mm/filemap.c:4112 udf_file_write_iter+0x2d5/0x6c0 fs/udf/file.c:111 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x548/0xa90 fs/read_write.c:686 ksys_pwrite64 fs/read_write.c:793 [inline] __do_sys_pwrite64 fs/read_write.c:801 [inline] __se_sys_pwrite64 fs/read_write.c:798 [inline] __x64_sys_pwrite64+0x193/0x220 fs/read_write.c:798 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: 0033:0x7f36e378e929 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:00007f36e45e7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f36e39b5fa0 RCX: 00007f36e378e929 RDX: 000000000000fdef RSI: 0000200000000140 RDI: 000000000000000e RBP: 00007f36e3810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fecc R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f36e39b5fa0 R15: 00007fff5ef0edf8