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list_del corruption, ffff88811d137528->next is LIST_POISON1 (dead000000000100)
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kernel BUG at lib/list_debug.c:55!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 21407 Comm: syz.5.5059 Not tainted 6.1.141-syzkaller-00025-g45271a2c461a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__list_del_entry_valid+0xea/0x130 lib/list_debug.c:53
Code: 48 89 de e8 20 45 7d 02 0f 0b 48 c7 c7 60 02 aa 85 48 89 de e8 0f 45 7d 02 0f 0b 48 c7 c7 c0 02 aa 85 48 89 de e8 fe 44 7d 02 <0f> 0b 48 c7 c7 20 03 aa 85 48 89 de e8 ed 44 7d 02 0f 0b 48 c7 c7
RSP: 0018:ffffc90009c0f4a0 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff88811d137528 RCX: 93dba8ae71c48900
RDX: ffffc90007f04000 RSI: 00000000000022bc RDI: 00000000000022bd
RBP: ffffc90009c0f4c0 R08: dffffc0000000000 R09: fffff52001381e35
R10: fffff52001381e35 R11: 1ffff92001381e34 R12: dffffc0000000000
R13: ffff88811c85f000 R14: dead000000000100 R15: dead000000000122
FS:  00007f3f7e9496c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff9a22fe8 CR3: 0000000119d24000 CR4: 00000000003506b0
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_version net/9p/client.c:-1 [inline]
 p9_client_create+0x8f8/0x1050 net/9p/client.c:1027
 v9fs_session_init+0x1dd/0x16a0 fs/9p/v9fs.c:408
 v9fs_mount+0xc5/0xaa0 fs/9p/vfs_super.c:126
 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:3054
 path_mount+0x675/0x1010 fs/namespace.c:3384
 do_mount fs/namespace.c:3397 [inline]
 __do_sys_mount fs/namespace.c:3605 [inline]
 __se_sys_mount+0x318/0x380 fs/namespace.c:3582
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3582
 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: 0033:0x7f3f7db8e929
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:00007f3f7e949038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3f7ddb6160 RCX: 00007f3f7db8e929
RDX: 0000200000000b80 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007f3f7dc10b39 R08: 0000200000000580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3f7ddb6160 R15: 00007fff707f06d8
 </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 20 45 7d 02 0f 0b 48 c7 c7 60 02 aa 85 48 89 de e8 0f 45 7d 02 0f 0b 48 c7 c7 c0 02 aa 85 48 89 de e8 fe 44 7d 02 <0f> 0b 48 c7 c7 20 03 aa 85 48 89 de e8 ed 44 7d 02 0f 0b 48 c7 c7
RSP: 0018:ffffc90009c0f4a0 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff88811d137528 RCX: 93dba8ae71c48900
RDX: ffffc90007f04000 RSI: 00000000000022bc RDI: 00000000000022bd
RBP: ffffc90009c0f4c0 R08: dffffc0000000000 R09: fffff52001381e35
R10: fffff52001381e35 R11: 1ffff92001381e34 R12: dffffc0000000000
R13: ffff88811c85f000 R14: dead000000000100 R15: dead000000000122
FS:  00007f3f7e9496c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff9a22fe8 CR3: 0000000119d24000 CR4: 00000000003506b0