list_del corruption, ffff8801b13f3028->next is LIST_POISON1 (dead000000000100)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:47!
invalid opcode: 0000 [#1] SMP KASAN
CPU: 0 PID: 13396 Comm: syz-executor412 Not tainted 4.18.0-rc4+ #41
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45
Code: 02 fe 0f 0b 4c 89 e2 48 89 de 48 c7 c7 a0 65 1a 88 e8 4a 6e 02 fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 40 65 1a 88 e8 36 6e 02 fe <0f> 0b 48 89 de 48 c7 c7 60 66 1a 88 e8 25 6e 02 fe 0f 0b 48 89 de 
RSP: 0018:ffff88019ce7f180 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffff8801b13f3028 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81631821 RDI: 0000000000000001
RBP: ffff88019ce7f198 R08: ffff8801b13aa380 R09: ffffed003b5c4fc0
R10: ffffed003b5c4fc0 R11: ffff8801dae27e07 R12: dead000000000200
R13: dead000000000100 R14: ffff8801b13f3028 R15: ffff8801b13f3030
FS:  0000000000000000(0000) GS:ffff8801dae00000(0063) knlGS:00000000f7f5cb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7f3bdb0 CR3: 00000001ba636000 CR4: 00000000001406f0
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+0x104/0x360 net/9p/trans_fd.c:690
 p9_client_rpc+0xf1f/0x1400 net/9p/client.c:800
 p9_client_version net/9p/client.c:976 [inline]
 p9_client_create+0xd09/0x16c9 net/9p/client.c:1069
 v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400
 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135
 mount_fs+0xae/0x328 fs/super.c:1277
 vfs_kern_mount.part.34+0xdc/0x4e0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:1027 [inline]
 do_new_mount fs/namespace.c:2518 [inline]
 do_mount+0x581/0x30e0 fs/namespace.c:2848
 __do_compat_sys_mount fs/compat.c:125 [inline]
 __se_compat_sys_mount fs/compat.c:92 [inline]
 __ia32_compat_sys_mount+0x5d5/0x860 fs/compat.c:92
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f60cb9
Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 
RSP: 002b:00000000f7f5c1ec EFLAGS: 00000286 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000200002c0
RDX: 0000000020000480 RSI: 0000000000000003 RDI: 0000000020000040
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace f474136a97f28e5c ]---
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45
Code: 02 fe 0f 0b 4c 89 e2 48 89 de 48 c7 c7 a0 65 1a 88 e8 4a 6e 02 fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 40 65 1a 88 e8 36 6e 02 fe <0f> 0b 48 89 de 48 c7 c7 60 66 1a 88 e8 25 6e 02 fe 0f 0b 48 89 de 
9pnet: Insufficient options for proto=fd
RSP: 0018:ffff88019ce7f180 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffff8801b13f3028 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81631821 RDI: 0000000000000001
RBP: ffff88019ce7f198 R08: ffff8801b13aa380 R09: ffffed003b5c4fc0
R10: ffffed003b5c4fc0 R11: ffff8801dae27e07 R12: dead000000000200
R13: dead000000000100 R14: ffff8801b13f3028 R15: ffff8801b13f3030
FS:  0000000000000000(0000) GS:ffff8801dae00000(0063) knlGS:00000000f7f5cb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f7f3bdb0 CR3: 00000001ba636000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400