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general protection fault in fib6_nh_get_excptn_bucket (3)

Status: closed as invalid on 2026/02/18 04:33
Subsystems: net
[Documentation on labels]
First crash: 98d, last: 73d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in fib6_nh_get_excptn_bucket net 2 1 264d 264d 0/29 closed as invalid on 2025/07/11 15:16
upstream general protection fault in fib6_nh_get_excptn_bucket (2) net 2 1 176d 176d 0/29 closed as invalid on 2025/09/29 07:16
upstream KASAN: slab-out-of-bounds Read in fib6_nh_get_excptn_bucket (3) net 17 2 1752d 1801d 0/29 auto-closed as invalid on 2021/09/13 13:28

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 1 UID: 0 PID: 10321 Comm: kworker/u32:21 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker
RIP: 0010:fib6_nh_get_excptn_bucket+0x11f/0x1e0 net/ipv6/route.c:1662
Code: 05 24 db 51 06 01 e8 b0 3e 7a f7 e9 2e ff ff ff e8 36 8d 9f f7 48 8d 7b 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a7 00 00 00 48 8b 5b 60 e8 de ad 58 01 31 ff 89
RSP: 0018:ffffc9000069fff0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8a1fbc73
RDX: 000000000000000c RSI: ffffffff8a1f595a RDI: 0000000000000060
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802aee54b0 R12: 0000000000000000
R13: fffff520000d402c R14: 1ffff920000d402d R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880d69f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000056c60000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 rt6_find_cached_rt+0x151/0x280 net/ipv6/route.c:1860
 ip6_pol_route+0x238/0x1230 net/ipv6/route.c:2276
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 __fib6_rule_action net/ipv6/fib6_rules.c:237 [inline]
 fib6_rule_action+0x283/0x910 net/ipv6/fib6_rules.c:275
 fib_rules_lookup+0x459/0x1030 net/core/fib_rules.c:339
 fib6_rule_lookup+0x18b/0x720 net/ipv6/fib6_rules.c:112
 ip6_route_output_flags_noref net/ipv6/route.c:2684 [inline]
 ip6_route_output_flags+0x1d0/0x640 net/ipv6/route.c:2696
 ip6_route_output include/net/ip6_route.h:93 [inline]
 ip6_dst_lookup_tail.constprop.0+0xa52/0x2140 net/ipv6/ip6_output.c:1141
 icmpv6_route_lookup+0x42d/0x570 net/ipv6/icmp.c:397
 icmp6_send+0xf2f/0x3c50 net/ipv6/icmp.c:794
 __icmpv6_send include/linux/icmpv6.h:28 [inline]
 icmpv6_send include/linux/icmpv6.h:49 [inline]
 __udp6_lib_rcv+0x2349/0x3090 net/ipv6/udp.c:1168
 ip6_protocol_deliver_rcu+0x6f0/0x1520 net/ipv6/ip6_input.c:438
 ip6_input_finish+0x1e4/0x4b0 net/ipv6/ip6_input.c:489
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip6_input+0x105/0x2f0 net/ipv6/ip6_input.c:500
 dst_input include/net/dst.h:474 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ipv6_rcv+0x264/0x650 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6137
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 process_backlog+0x4a2/0x1650 net/core/dev.c:6602
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 do_softirq kernel/softirq.c:523 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:510
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450
 wg_socket_send_skb_to_peer+0x145/0x210 drivers/net/wireguard/socket.c:184
 wg_socket_send_buffer_to_peer+0x148/0x1a0 drivers/net/wireguard/socket.c:200
 wg_packet_send_handshake_initiation+0x225/0x360 drivers/net/wireguard/send.c:40
 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:fib6_nh_get_excptn_bucket+0x11f/0x1e0 net/ipv6/route.c:1662
Code: 05 24 db 51 06 01 e8 b0 3e 7a f7 e9 2e ff ff ff e8 36 8d 9f f7 48 8d 7b 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a7 00 00 00 48 8b 5b 60 e8 de ad 58 01 31 ff 89
RSP: 0018:ffffc9000069fff0 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8a1fbc73
RDX: 000000000000000c RSI: ffffffff8a1f595a RDI: 0000000000000060
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802aee54b0 R12: 0000000000000000
R13: fffff520000d402c R14: 1ffff920000d402d R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880d69f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000e184000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	05 24 db 51 06       	add    $0x651db24,%eax
   5:	01 e8                	add    %ebp,%eax
   7:	b0 3e                	mov    $0x3e,%al
   9:	7a f7                	jp     0x2
   b:	e9 2e ff ff ff       	jmp    0xffffff3e
  10:	e8 36 8d 9f f7       	call   0xf79f8d4b
  15:	48 8d 7b 60          	lea    0x60(%rbx),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 a7 00 00 00    	jne    0xdb
  34:	48 8b 5b 60          	mov    0x60(%rbx),%rbx
  38:	e8 de ad 58 01       	call   0x158ae1b
  3d:	31 ff                	xor    %edi,%edi
  3f:	89                   	.byte 0x89

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/20 10:45 upstream dd9b004b7ff3 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in fib6_nh_get_excptn_bucket
2025/12/10 23:30 upstream 0048fbb4011e d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in fib6_nh_get_excptn_bucket
2025/11/25 08:37 upstream ac3fd01e4c1e 64219f15 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in fib6_nh_get_excptn_bucket
* Struck through repros no longer work on HEAD.