syzbot

list_del corruption, ffff88805af61610->next is LIST_POISON1 (dead000000000100)
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kernel BUG at lib/list_debug.c:56!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 10605 Comm: syz.0.1206 Not tainted 6.11.0-rc7-syzkaller-00133-ge936e7d4a83b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:__list_del_entry_valid_or_report+0x108/0x1c0 lib/list_debug.c:56
Code: c7 c7 e0 fe b0 8b e8 97 5e de fc 90 0f 0b 48 c7 c7 40 ff b0 8b e8 88 5e de fc 90 0f 0b 48 c7 c7 a0 ff b0 8b e8 79 5e de fc 90 <0f> 0b 48 89 ca 48 c7 c7 00 00 b1 8b e8 67 5e de fc 90 0f 0b 48 89
RSP: 0018:ffffc9000455f6d0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff88805af61550 RCX: ffffc9000f602000
RDX: 0000000000000000 RSI: ffffffff816ceea6 RDI: 0000000000000005
RBP: ffff888025047800 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000001 R12: ffff88805c934830
R13: 0000000000000005 R14: ffff88805af61610 R15: ffff88805af61618
FS:  00007fedb6f3b6c0(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f375bdfc408 CR3: 000000001eab8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry_valid include/linux/list.h:124 [inline]
 __list_del_entry include/linux/list.h:215 [inline]
 list_del include/linux/list.h:229 [inline]
 p9_fd_cancelled+0xa2/0x2a0 net/9p/trans_fd.c:736
 p9_client_flush.isra.0+0x34b/0x420 net/9p/client.c:618
 p9_client_rpc+0xaef/0xc10 net/9p/client.c:741
 p9_client_version net/9p/client.c:930 [inline]
 p9_client_create+0xcc8/0x1210 net/9p/client.c:1034
 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410
 v9fs_mount+0xc6/0xa50 fs/9p/vfs_super.c:122
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1800
 do_new_mount fs/namespace.c:3472 [inline]
 path_mount+0x14e6/0x1f20 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount fs/namespace.c:3997 [inline]
 __x64_sys_mount+0x294/0x320 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fedb617def9
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:00007fedb6f3b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fedb6336130 RCX: 00007fedb617def9
RDX: 0000000020000b80 RSI: 0000000020000040 RDI: 0000000000000000
RBP: 00007fedb61f0b76 R08: 0000000020000180 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fedb6336130 R15: 00007ffd5f34b4f8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid_or_report+0x108/0x1c0 lib/list_debug.c:56
Code: c7 c7 e0 fe b0 8b e8 97 5e de fc 90 0f 0b 48 c7 c7 40 ff b0 8b e8 88 5e de fc 90 0f 0b 48 c7 c7 a0 ff b0 8b e8 79 5e de fc 90 <0f> 0b 48 89 ca 48 c7 c7 00 00 b1 8b e8 67 5e de fc 90 0f 0b 48 89
RSP: 0018:ffffc9000455f6d0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff88805af61550 RCX: ffffc9000f602000
RDX: 0000000000000000 RSI: ffffffff816ceea6 RDI: 0000000000000005
RBP: ffff888025047800 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000001 R12: ffff88805c934830
R13: 0000000000000005 R14: ffff88805af61610 R15: ffff88805af61618
FS:  00007fedb6f3b6c0(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f375bdfc408 CR3: 000000001eab8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400