list_del corruption, ffff888135013208->next is LIST_POISON1 (dead000000000100)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:55!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 1925 Comm: syz.1.9890 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__list_del_entry_valid+0xea/0x130 lib/list_debug.c:53
Code: 48 89 de e8 60 76 80 02 0f 0b 48 c7 c7 a0 0e aa 85 48 89 de e8 4f 76 80 02 0f 0b 48 c7 c7 00 0f aa 85 48 89 de e8 3e 76 80 02 <0f> 0b 48 c7 c7 60 0f aa 85 48 89 de e8 2d 76 80 02 0f 0b 48 c7 c7
RSP: 0018:ffffc9000692f780 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff888135013208 RCX: 3bef631753003100
RDX: ffffc90009c64000 RSI: 000000000000b05f RDI: 000000000000b060
RBP: ffffc9000692f7a0 R08: dffffc0000000000 R09: fffff52000d25e91
R10: fffff52000d25e91 R11: 1ffff92000d25e90 R12: dffffc0000000000
R13: ffff88812fc7d600 R14: dead000000000100 R15: dead000000000122
FS:  00007f904fe6c6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000021000 CR3: 000000010386d000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry include/linux/list.h:134 [inline]
 list_del include/linux/list.h:148 [inline]
 p9_fd_cancelled+0xa1/0x230 net/9p/trans_fd.c:734
 p9_client_flush+0x2e7/0x390 net/9p/client.c:614
 p9_client_rpc+0x83d/0xac0 net/9p/client.c:734
 p9_client_stat+0xf5/0x330 net/9p/client.c:1692
 v9fs_mount+0x6cf/0xaa0 fs/9p/vfs_super.c:172
 legacy_get_tree+0xfe/0x1a0 fs/fs_context.c:632
 vfs_get_tree+0x9a/0x270 fs/super.c:1575
 do_new_mount+0x25a/0xa20 fs/namespace.c:3058
 path_mount+0x675/0x1010 fs/namespace.c:3388
 do_mount fs/namespace.c:3401 [inline]
 __do_sys_mount fs/namespace.c:3609 [inline]
 __se_sys_mount+0x318/0x380 fs/namespace.c:3586
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3586
 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f904ef8ebe9
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:00007f904fe6c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f904f1c6180 RCX: 00007f904ef8ebe9
RDX: 0000200000000b80 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007f904f011e19 R08: 0000200000000580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f904f1c6218 R14: 00007f904f1c6180 R15: 00007ffee1971ca8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid+0xea/0x130 lib/list_debug.c:53
Code: 48 89 de e8 60 76 80 02 0f 0b 48 c7 c7 a0 0e aa 85 48 89 de e8 4f 76 80 02 0f 0b 48 c7 c7 00 0f aa 85 48 89 de e8 3e 76 80 02 <0f> 0b 48 c7 c7 60 0f aa 85 48 89 de e8 2d 76 80 02 0f 0b 48 c7 c7
RSP: 0018:ffffc9000692f780 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff888135013208 RCX: 3bef631753003100
RDX: ffffc90009c64000 RSI: 000000000000b05f RDI: 000000000000b060
RBP: ffffc9000692f7a0 R08: dffffc0000000000 R09: fffff52000d25e91
R10: fffff52000d25e91 R11: 1ffff92000d25e90 R12: dffffc0000000000
R13: ffff88812fc7d600 R14: dead000000000100 R15: dead000000000122
FS:  00007f904fe6c6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000021000 CR3: 000000010386d000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400