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list_del corruption, ffff88811db03848->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: 5726 Comm: syz.6.1504 Tainted: G        W         5.15.184-syzkaller-00118-g4b77ae0e7f58 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__list_del_entry_valid+0xea/0x120 lib/list_debug.c:53
Code: 48 89 de e8 78 64 4c 02 0f 0b 48 c7 c7 20 30 63 85 48 89 de e8 67 64 4c 02 0f 0b 48 c7 c7 80 30 63 85 48 89 de e8 56 64 4c 02 <0f> 0b 48 c7 c7 e0 30 63 85 48 89 de e8 45 64 4c 02 0f 0b 48 c7 c7
RSP: 0018:ffffc90001a374c0 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff88811db03848 RCX: 8ccf42d20133e500
RDX: ffffc9000d18f000 RSI: 00000000000074ac RDI: 00000000000074ad
RBP: ffffc90001a374e0 R08: dffffc0000000000 R09: ffffed103ee065e8
R10: ffffed103ee065e8 R11: 1ffff1103ee065e7 R12: dffffc0000000000
R13: ffff88811c159a00 R14: dead000000000100 R15: dead000000000122
FS:  00007fbd9c2866c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558dfbf4a8 CR3: 000000012374e000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_del_entry include/linux/list.h:132 [inline]
 list_del include/linux/list.h:146 [inline]
 p9_fd_cancelled+0xa1/0x230 net/9p/trans_fd.c:736
 p9_client_flush+0x2d9/0x3e0 net/9p/client.c:681
 p9_client_rpc+0x844/0x1070 net/9p/client.c:788
 p9_client_version net/9p/client.c:-1 [inline]
 p9_client_create+0x8dd/0x1010 net/9p/client.c:1058
 v9fs_session_init+0x1dd/0x16f0 fs/9p/v9fs.c:409
 v9fs_mount+0x76/0x7e0 fs/9p/vfs_super.c:126
 legacy_get_tree+0xed/0x190 fs/fs_context.c:611
 vfs_get_tree+0x89/0x260 fs/super.c:1530
 do_new_mount+0x25a/0xa20 fs/namespace.c:3014
 path_mount+0x675/0x1020 fs/namespace.c:3344
 do_mount fs/namespace.c:3357 [inline]
 __do_sys_mount fs/namespace.c:3565 [inline]
 __se_sys_mount+0x318/0x380 fs/namespace.c:3542
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3542
 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbd9dc5f969
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:00007fbd9c286038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fbd9de87160 RCX: 00007fbd9dc5f969
RDX: 0000200000000b80 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007fbd9dce1ab1 R08: 0000200000000580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbd9de87160 R15: 00007ffc15855748
 </TASK>
Modules linked in:
---[ end trace 204e9b995d23826d ]---
RIP: 0010:__list_del_entry_valid+0xea/0x120 lib/list_debug.c:53
Code: 48 89 de e8 78 64 4c 02 0f 0b 48 c7 c7 20 30 63 85 48 89 de e8 67 64 4c 02 0f 0b 48 c7 c7 80 30 63 85 48 89 de e8 56 64 4c 02 <0f> 0b 48 c7 c7 e0 30 63 85 48 89 de e8 45 64 4c 02 0f 0b 48 c7 c7
RSP: 0018:ffffc90001a374c0 EFLAGS: 00010246
RAX: 000000000000004e RBX: ffff88811db03848 RCX: 8ccf42d20133e500
RDX: ffffc9000d18f000 RSI: 00000000000074ac RDI: 00000000000074ad
RBP: ffffc90001a374e0 R08: dffffc0000000000 R09: ffffed103ee065e8
R10: ffffed103ee065e8 R11: 1ffff1103ee065e7 R12: dffffc0000000000
R13: ffff88811c159a00 R14: dead000000000100 R15: dead000000000122
FS:  00007fbd9c2866c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558dfbf4a8 CR3: 000000012374e000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400