VFS: Found a Xenix FS (block size = 1024) on device loop4
Bad inode number on dev loop4: 2 is out of range
SysV FS: get root inode failed
------------[ cut here ]------------
VFS: brelse: Trying to free free buffer
WARNING: CPU: 0 PID: 4285 at fs/buffer.c:1148 __brelse+0x6b/0x90 fs/buffer.c:1148
Modules linked in:
CPU: 0 PID: 4285 Comm: syz.4.13 Not tainted 5.15.170-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__brelse+0x6b/0x90 fs/buffer.c:1148
Code: 74 17 e8 98 ac 9a ff 48 89 df be 04 00 00 00 e8 fb 78 e4 ff f0 ff 0b eb 13 e8 81 ac 9a ff 48 c7 c7 a0 6b 97 8a e8 25 48 66 ff <0f> 0b 5b 5d c3 89 d9 80 e1 07 80 c1 03 38 c1 7c b8 48 89 df e8 1c
RSP: 0018:ffffc90004867bd8 EFLAGS: 00010246
RAX: 603b1396d0eb0b00 RBX: ffff888074b37318 RCX: 0000000000040000
RDX: ffffc900059e2000 RSI: 000000000003c6e6 RDI: 000000000003c6e7
RBP: 0000000000000000 R08: ffffffff81669a2c R09: ffffed10172067a8
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888074b372b8
R13: ffff8880212e4000 R14: ffff888074b372b8 R15: ffff88801e836000
FS:  00007f9e2a0816c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f509baa0000 CR3: 000000006188e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 brelse include/linux/buffer_head.h:325 [inline]
 sysv_fill_super+0x69e/0x790 fs/sysv/super.c:415
 mount_bdev+0x2c9/0x3f0 fs/super.c:1400
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3012
 do_mount fs/namespace.c:3355 [inline]
 __do_sys_mount fs/namespace.c:3563 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9e2bc0aeba
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f9e2a080e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9e2a080ef0 RCX: 00007f9e2bc0aeba
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f9e2a080eb0
RBP: 0000000020000000 R08: 00007f9e2a080ef0 R09: 0000000002000412
R10: 0000000002000412 R11: 0000000000000246 R12: 0000000020000100
R13: 00007f9e2a080eb0 R14: 0000000000009eb5 R15: 0000000020000040
 </TASK>