syzbot


WARNING in nf_conntrack_cleanup_net_list

Status: upstream: reported on 2025/12/11 18:38
Subsystems: netfilter
[Documentation on labels]
Reported-by: syzbot+4393c47753b7808dac7d@syzkaller.appspotmail.com
Fix commit: 2ef02ac38d3c inet: frags: drop fraglist conntrack references
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci-upstream-rust-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-upstream-gce-arm64]
First crash: 88d, last: 9h01m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
d1f37317-0bd3-4ac6-8037-0d058106fbb9 repro WARNING in nf_conntrack_cleanup_net_list 2026/03/07 08:22 2026/03/07 08:22 2026/03/07 08:31 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Discussions (2)
Title Replies (including bot) Last reply
[PATCH net] inet: frags: drop fraglist conntrack references 3 (3) 2026/01/04 20:13
[syzbot] [netfilter?] WARNING in nf_conntrack_cleanup_net_list 6 (7) 2025/12/13 18:54

Sample crash report:
------------[ cut here ]------------
conntrack cleanup blocked for 60s
WARNING: net/netfilter/nf_conntrack_core.c:2511 at nf_conntrack_cleanup_net_list+0x4f7/0x690 net/netfilter/nf_conntrack_core.c:2511, CPU#0: kworker/u8:5/86
Modules linked in:
CPU: 0 UID: 0 PID: 86 Comm: kworker/u8:5 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: netns cleanup_net
RIP: 0010:nf_conntrack_cleanup_net_list+0x4f7/0x690 net/netfilter/nf_conntrack_core.c:2511
Code: 29 c3 48 89 de e8 c9 c3 5a f8 48 85 db 78 0f e8 df c8 5a f8 e8 5a cf e2 01 e9 0e fc ff ff e8 d0 c8 5a f8 48 8d 3d 79 1d 3a 07 <67> 48 0f b9 3a eb de 4c 8b 6c 24 40 e8 b8 c8 5a f8 48 b8 00 00 00
RSP: 0018:ffffc9000258f970 EFLAGS: 00010293
RAX: 0000000000000000 RBX: fffffffffffffffe RCX: ffffffff89adf177
RDX: ffff88801eb9a4c0 RSI: ffffffff89adf190 RDI: ffffffff90e80f10
RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000
R10: fffffffffffffffe R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000001 R14: ffffc9000258fb28 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124347000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdaca8de80 CR3: 00000000353f7000 CR4: 00000000003526f0
DR0: 0000000040000005 DR1: 0000000100000003 DR2: 0000000000000898
DR3: 0000000000400008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ops_exit_list net/core/net_namespace.c:205 [inline]
 ops_undo_list+0x363/0xab0 net/core/net_namespace.c:252
 cleanup_net+0x499/0x920 net/core/net_namespace.c:704
 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
 process_scheduled_works kernel/workqueue.c:3358 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	29 c3                	sub    %eax,%ebx
   2:	48 89 de             	mov    %rbx,%rsi
   5:	e8 c9 c3 5a f8       	call   0xf85ac3d3
   a:	48 85 db             	test   %rbx,%rbx
   d:	78 0f                	js     0x1e
   f:	e8 df c8 5a f8       	call   0xf85ac8f3
  14:	e8 5a cf e2 01       	call   0x1e2cf73
  19:	e9 0e fc ff ff       	jmp    0xfffffc2c
  1e:	e8 d0 c8 5a f8       	call   0xf85ac8f3
  23:	48 8d 3d 79 1d 3a 07 	lea    0x73a1d79(%rip),%rdi        # 0x73a1da3
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	eb de                	jmp    0xf
  31:	4c 8b 6c 24 40       	mov    0x40(%rsp),%r13
  36:	e8 b8 c8 5a f8       	call   0xf85ac8f3
  3b:	48                   	rex.W
  3c:	b8                   	.byte 0xb8
  3d:	00 00                	add    %al,(%rax)

Crashes (631):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/09 09:01 upstream 014441d1e4b2 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in nf_conntrack_cleanup_net_list
2026/03/08 05:13 upstream c23719abc330 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/03/03 09:15 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in nf_conntrack_cleanup_net_list
2026/03/03 04:07 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/03/03 03:06 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in nf_conntrack_cleanup_net_list
2026/03/01 20:54 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/02/28 07:45 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/02/27 22:26 upstream aed968f8a6cd 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in nf_conntrack_cleanup_net_list
2026/02/27 12:50 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/02/27 06:44 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in nf_conntrack_cleanup_net_list
2026/02/26 19:18 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/02/26 03:26 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/02/25 07:59 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/02/25 05:47 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2026/02/25 01:33 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in nf_conntrack_cleanup_net_list
2026/02/24 16:37 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in nf_conntrack_cleanup_net_list
2026/02/23 15:30 upstream 6de23f81a5e0 305c0ec5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/03/07 02:32 upstream 651690480a96 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_conntrack_cleanup_net_list
2026/02/27 17:58 upstream a75cb869a8cc 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_conntrack_cleanup_net_list
2026/03/03 08:30 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/02 20:23 upstream 11439c4635ed b9dd6534 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/02 17:42 upstream 11439c4635ed b9dd6534 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/02 13:37 upstream 11439c4635ed b9dd6534 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/02 09:24 upstream 39c633261414 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/02 00:19 upstream 39c633261414 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/01 23:04 upstream 39c633261414 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/28 12:05 upstream 4d349ee5c778 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/27 21:20 upstream a75cb869a8cc 2cf092b8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/27 20:26 upstream a75cb869a8cc 2cf092b8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/27 16:32 upstream a75cb869a8cc 2cf092b8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/27 05:01 upstream 3f4a08e64442 a2f13f71 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/26 06:49 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/26 04:44 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/26 00:10 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/25 14:50 upstream 7dff99b35460 c162cde9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/25 13:25 upstream 7dff99b35460 c162cde9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/25 08:39 upstream 7dff99b35460 787dfb7c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/25 02:52 upstream 7dff99b35460 787dfb7c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/24 18:55 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/24 13:18 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/24 10:47 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/23 23:45 upstream 7dff99b35460 41d2fa6a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/23 08:53 upstream 6de23f81a5e0 6e7b5511 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/02/22 22:05 upstream 189f164e573e 6e7b5511 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_conntrack_cleanup_net_list
2026/03/05 21:04 upstream c107785c7e8d d20b04c8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in nf_conntrack_cleanup_net_list
2026/03/05 09:18 upstream ecc64d2dc9ff a9fe5c9e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in nf_conntrack_cleanup_net_list
2026/03/04 23:59 upstream ecc64d2dc9ff a9fe5c9e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in nf_conntrack_cleanup_net_list
2026/01/18 00:08 upstream d3eeb99bbc99 56f88057 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in nf_conntrack_cleanup_net_list
2026/03/04 04:50 net 46d0d6f50dab 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/03/06 18:48 net-next e5e09233e8a9 41d8037d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/03/02 23:49 net-next 01857fc712f6 b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/03/01 10:59 net-next 01857fc712f6 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/02/25 21:06 net-next d2adf01780b8 df2e85d4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_conntrack_cleanup_net_list
2026/03/04 17:46 linux-next fc7b1a72c6cd e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
2025/12/11 05:14 linux-next 5ce74bc1b7cb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in nf_conntrack_cleanup_net_list
* Struck through repros no longer work on HEAD.