list_del corruption, ffff8801b4338028->next is LIST_POISON1 (dead000000000100)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:47!
invalid opcode: 0000 [#1] SMP PTI
CPU: 1 PID: 4682 Comm: syz-executor480 Not tainted 4.18.0-rc4+ #24
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0x223/0x440 lib/list_debug.c:45
Code: 48 c7 81 80 0c 00 00 00 00 00 00 c7 81 20 03 00 00 00 00 00 00 48 c7 c7 be f6 dc 8a 31 c0 48 8b 75 c0 4c 89 f2 e8 fd ac 2b fd <0f> 0b 90 66 2e 0f 1f 84 00 00 00 00 00 eb fe 8b 7d b4 e8 76 61 ae 
RSP: 0018:ffff8801b28ff520 EFLAGS: 00010246
RAX: 000000000000004e RBX: 0000000000000000 RCX: 349a739139e39a00
RDX: 0000000000000000 RSI: aaaaaaaaaaaab000 RDI: ffffea000cbef440
RBP: ffff8801b28ff578 R08: 0000000000480020 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff8675b580 R12: 0000000000000000
R13: dead000000000100 R14: dead000000000100 R15: dead000000000200
FS:  00007fb0bd569700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb0bd568e78 CR3: 00000001ae1e6000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_del_entry include/linux/list.h:117 [inline]
 list_del include/linux/list.h:125 [inline]
 p9_fd_cancel+0xca/0x360 net/9p/trans_fd.c:690
 p9_client_rpc+0xba0/0x1dc0 net/9p/client.c:800
 p9_client_create+0x15a8/0x2110 net/9p/client.c:966
 v9fs_session_init+0x329/0x2970 fs/9p/v9fs.c:400
 v9fs_mount+0x107/0x11b0 fs/9p/vfs_super.c:135
 mount_fs+0x29b/0x780 fs/super.c:1277
 vfs_kern_mount+0x222/0x990 fs/namespace.c:1037
 do_new_mount fs/namespace.c:2518 [inline]
 do_mount+0xd30/0x5310 fs/namespace.c:2848
 ksys_mount+0x32e/0x3d0 fs/namespace.c:3064
 __do_sys_mount fs/namespace.c:3078 [inline]
 __se_sys_mount fs/namespace.c:3075 [inline]
 __x64_sys_mount+0x157/0x1c0 fs/namespace.c:3075
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x445da9
Code: e8 ec ba 02 00 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 ab 0e fc ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007fb0bd568da8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc3c RCX: 0000000000445da9
RDX: 00000000200001c0 RSI: 0000000020000100 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000020000200 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000006dbc38
R13: 0030656c69662f2e R14: 64663d736e617274 R15: 0000000000000004
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace d79bec730f97664c ]---
RIP: 0010:__list_del_entry_valid+0x223/0x440 lib/list_debug.c:45
Code: 48 c7 81 80 0c 00 00 00 00 00 00 c7 81 20 03 00 00 00 00 00 00 48 c7 c7 be f6 dc 8a 31 c0 48 8b 75 c0 4c 89 f2 e8 fd ac 2b fd <0f> 0b 90 66 2e 0f 1f 84 00 00 00 00 00 eb fe 8b 7d b4 e8 76 61 ae 
RSP: 0018:ffff8801b28ff520 EFLAGS: 00010246
RAX: 000000000000004e RBX: 0000000000000000 RCX: 349a739139e39a00
RDX: 0000000000000000 RSI: aaaaaaaaaaaab000 RDI: ffffea000cbef440
RBP: ffff8801b28ff578 R08: 0000000000480020 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff8675b580 R12: 0000000000000000
R13: dead000000000100 R14: dead000000000100 R15: dead000000000200
FS:  00007fb0bd569700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb0bd568e78 CR3: 00000001ae1e6000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400