syzbot


kernel BUG in ip6_pol_route (2)

Status: upstream: reported C repro on 2025/11/15 18:59
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+9b35e9bc0951140d13e6@syzkaller.appspotmail.com
Fix commit: 1adaea51c61b ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT
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-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-gce-arm64 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], missing on: [ci-qemu2-riscv64 ci-upstream-bpf-next-kasan-gce ci2-upstream-usb]
First crash: 60d, last: 11d
Cause bisection: failed (error log, bisect log)
  
Discussions (5)
Title Replies (including bot) Last reply
[PATCH net v4] ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT 2 (2) 2025/12/30 11:20
[PATCH net v2] ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT 5 (5) 2025/12/23 02:38
[PATCH net v3] ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT 1 (1) 2025/12/22 12:42
[PATCH net-next v1] ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT 3 (3) 2025/12/18 21:06
[syzbot] [net?] kernel BUG in ip6_pol_route (2) 0 (2) 2025/12/01 02:32
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in ip6_pol_route net -1 597 60d 101d 0/29 closed as invalid on 2025/11/11 16:41

Sample crash report:
------------[ cut here ]------------
kernel BUG at net/ipv6/route.c:1473!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 6073 Comm: syz.2.34 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rt6_make_pcpu_route net/ipv6/route.c:1473 [inline]
RIP: 0010:ip6_pol_route+0x117d/0x1180 net/ipv6/route.c:2305
Code: aa f8 e9 f4 fa ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 03 fb ff ff 48 89 df e8 9e cf aa f8 e9 f6 fa ff ff e8 64 0d 49 f8 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e
RSP: 0018:ffffc9000407f5a0 EFLAGS: 00010293
RAX: ffffffff89759fdc RBX: ffff888126ef4000 RCX: ffff88802ea13c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000407f6b0 R08: ffffe8ffffd488af R09: 1ffffd1ffffa9115
R10: dffffc0000000000 R11: fffff91ffffa9116 R12: ffff888031da18c0
R13: ffffffff89758fc2 R14: dffffc0000000000 R15: 0000607ed8e548a8
FS:  0000555563d45500(0000) GS:ffff888126ef4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8a8bbe1760 CR3: 0000000031586000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x1fc/0x6f0 net/ipv6/fib6_rules.c:120
 ip6_route_output_flags_noref net/ipv6/route.c:2684 [inline]
 ip6_route_output_flags+0x364/0x5d0 net/ipv6/route.c:2696
 ip6_route_output include/net/ip6_route.h:93 [inline]
 ip6_dst_lookup_tail+0x1ae/0x1510 net/ipv6/ip6_output.c:1141
 ip6_dst_lookup_flow+0x47/0xe0 net/ipv6/ip6_output.c:1272
 tcp_v6_connect+0xbdb/0x18a0 net/ipv6/tcp_ipv6.c:281
 __inet_stream_connect+0x2ae/0xe70 net/ipv4/af_inet.c:679
 inet_stream_connect+0x66/0xa0 net/ipv4/af_inet.c:750
 __sys_connect_file net/socket.c:2102 [inline]
 __sys_connect+0x323/0x450 net/socket.c:2121
 __do_sys_connect net/socket.c:2127 [inline]
 __se_sys_connect net/socket.c:2124 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2124
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b578bf749
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:00007ffeb60b5268 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f7b57b15fa0 RCX: 00007f7b578bf749
RDX: 000000000000001c RSI: 0000200000000200 RDI: 0000000000000003
RBP: 00007f7b57943f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b57b15fa0 R14: 00007f7b57b15fa0 R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:rt6_make_pcpu_route net/ipv6/route.c:1473 [inline]
RIP: 0010:ip6_pol_route+0x117d/0x1180 net/ipv6/route.c:2305
Code: aa f8 e9 f4 fa ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 03 fb ff ff 48 89 df e8 9e cf aa f8 e9 f6 fa ff ff e8 64 0d 49 f8 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e
RSP: 0018:ffffc9000407f5a0 EFLAGS: 00010293
RAX: ffffffff89759fdc RBX: ffff888126ef4000 RCX: ffff88802ea13c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000407f6b0 R08: ffffe8ffffd488af R09: 1ffffd1ffffa9115
R10: dffffc0000000000 R11: fffff91ffffa9116 R12: ffff888031da18c0
R13: ffffffff89758fc2 R14: dffffc0000000000 R15: 0000607ed8e548a8
FS:  0000555563d45500(0000) GS:ffff888126ef4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f53a449f358 CR3: 0000000031586000 CR4: 00000000003526f0

Crashes (1134):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/01 02:32 upstream e69c7c175115 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 17:56 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 15:37 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 14:35 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 13:18 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/30 11:08 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 09:24 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/30 08:11 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 06:55 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 05:25 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 04:04 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/30 01:54 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/30 00:54 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/29 23:45 upstream 8640b74557fc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 19:54 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 16:46 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/29 15:36 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 14:21 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 12:53 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 10:40 upstream 7839932417dd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 09:28 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/29 08:11 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 07:01 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 06:08 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 03:31 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/29 02:26 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 21:48 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 20:47 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 17:16 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 15:44 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 14:40 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 14:07 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 11:04 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 09:03 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 07:49 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 05:04 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/28 03:14 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/28 01:11 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/27 21:55 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/27 20:28 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/27 18:50 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/27 17:11 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/12/27 14:57 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/27 13:26 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root kernel BUG in ip6_pol_route
2025/12/27 12:16 upstream c53f467229a7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/11/15 18:54 upstream 7a0892d2836e f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
2025/11/11 18:46 upstream 4427259cc7f7 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in ip6_pol_route
* Struck through repros no longer work on HEAD.