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general protection fault in rt6_find_cached_rt (2)

Status: closed as invalid on 2026/02/13 20:07
Subsystems: net
[Documentation on labels]
First crash: 134d, last: 64d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in rt6_find_cached_rt net 2 3 282d 323d 0/29 auto-obsoleted due to no activity on 2025/09/22 19:38
linux-6.1 BUG: unable to handle kernel paging request in rt6_find_cached_rt 8 1 109d 109d 0/3 auto-obsoleted due to no activity on 2026/03/14 11:37

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:fib6_nh_get_excptn_bucket net/ipv6/route.c:1673 [inline]
RIP: 0010:rt6_find_cached_rt+0xb9/0x270 net/ipv6/route.c:1871
Code: 48 c1 e8 03 48 89 44 24 08 48 8b 44 24 08 80 3c 18 00 74 08 4c 89 f7 e8 c5 26 1c f8 49 8b 2e 48 83 c5 60 48 89 e8 48 c1 e8 03 <80> 3c 18 00 74 08 48 89 ef e8 a9 26 1c f8 4c 8b 6d 00 e8 60 41 4f
RSP: 0018:ffffc90000006de0 EFLAGS: 00010206
RAX: 000000000000000c RBX: dffffc0000000000 RCX: 0000000000000100
RDX: ffffffff8dc95340 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000060 R08: ffff88802985d833 R09: 1ffff1100530bb06
R10: dffffc0000000000 R11: ffffed100530bb07 R12: ffffc90000006eb8
R13: 0000000000000000 R14: ffffc90000006eb0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125e1e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05aed72a60 CR3: 0000000059e42000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 ip6_pol_route+0x296/0x11a0 net/ipv6/route.c:2287
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x348/0x6f0 net/ipv6/fib6_rules.c:125
 ip6_route_output_flags_noref net/ipv6/route.c:2695 [inline]
 ip6_route_output_flags+0x364/0x5d0 net/ipv6/route.c:2707
 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
 udp_tunnel6_dst_lookup+0x234/0x420 net/ipv6/ip6_udp_tunnel.c:165
 geneve6_xmit_skb drivers/net/geneve.c:960 [inline]
 geneve_xmit+0xd1a/0x2b90 drivers/net/geneve.c:1047
 __netdev_start_xmit include/linux/netdevice.h:5273 [inline]
 netdev_start_xmit include/linux/netdevice.h:5282 [inline]
 xmit_one net/core/dev.c:3866 [inline]
 dev_hard_start_xmit+0x2cd/0x800 net/core/dev.c:3882
 __dev_queue_xmit+0x144f/0x3100 net/core/dev.c:4832
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip6_output+0x340/0x550 net/ipv6/ip6_output.c:247
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ndisc_send_skb+0xbce/0x1510 net/ipv6/ndisc.c:512
 addrconf_rs_timer+0x369/0x6a0 net/ipv6/addrconf.c:4037
 call_timer_fn+0x16e/0x590 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404
 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 21 0e 00 f3 0f 1e fa fb f4 <e9> 08 e3 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07dc0 EFLAGS: 000002c6
RAX: 00000000014854c3 RBX: ffffffff8197149e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d793611 RDI: ffffffff8bc084e0
RBP: ffffffff8dc07eb0 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f822d70
R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
 rest_init+0x2de/0x300 init/main.c:757
 start_kernel+0x381/0x3d0 init/main.c:1206
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:fib6_nh_get_excptn_bucket net/ipv6/route.c:1673 [inline]
RIP: 0010:rt6_find_cached_rt+0xb9/0x270 net/ipv6/route.c:1871
Code: 48 c1 e8 03 48 89 44 24 08 48 8b 44 24 08 80 3c 18 00 74 08 4c 89 f7 e8 c5 26 1c f8 49 8b 2e 48 83 c5 60 48 89 e8 48 c1 e8 03 <80> 3c 18 00 74 08 48 89 ef e8 a9 26 1c f8 4c 8b 6d 00 e8 60 41 4f
RSP: 0018:ffffc90000006de0 EFLAGS: 00010206
RAX: 000000000000000c RBX: dffffc0000000000 RCX: 0000000000000100
RDX: ffffffff8dc95340 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000060 R08: ffff88802985d833 R09: 1ffff1100530bb06
R10: dffffc0000000000 R11: ffffed100530bb07 R12: ffffc90000006eb8
R13: 0000000000000000 R14: ffffc90000006eb0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125e1e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05aed72a60 CR3: 0000000059e42000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	48 c1 e8 03          	shr    $0x3,%rax
   4:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
   9:	48 8b 44 24 08       	mov    0x8(%rsp),%rax
   e:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  12:	74 08                	je     0x1c
  14:	4c 89 f7             	mov    %r14,%rdi
  17:	e8 c5 26 1c f8       	call   0xf81c26e1
  1c:	49 8b 2e             	mov    (%r14),%rbp
  1f:	48 83 c5 60          	add    $0x60,%rbp
  23:	48 89 e8             	mov    %rbp,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	48 89 ef             	mov    %rbp,%rdi
  33:	e8 a9 26 1c f8       	call   0xf81c26e1
  38:	4c 8b 6d 00          	mov    0x0(%rbp),%r13
  3c:	e8                   	.byte 0xe8
  3d:	60                   	(bad)
  3e:	41                   	rex.B
  3f:	4f                   	rex.WRXB

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/18 14:37 upstream e84d960149e7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in rt6_find_cached_rt
2026/01/09 15:24 upstream 623fb9912f6a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in rt6_find_cached_rt
2026/01/09 12:54 upstream 623fb9912f6a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in rt6_find_cached_rt
2025/12/20 07:14 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in rt6_find_cached_rt
2025/11/30 17:05 upstream 6bda50f4333f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in rt6_find_cached_rt
2025/11/25 08:55 upstream ac3fd01e4c1e 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in rt6_find_cached_rt
2025/11/09 17:15 upstream 439fc29dfd3b 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in rt6_find_cached_rt
2025/12/12 05:31 net 885bebac9909 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/11 20:44 net 885bebac9909 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/10 22:23 net 5ace7ef87f05 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/04 05:30 net 8f7aa3d3c732 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/04 05:29 net 8f7aa3d3c732 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/04 05:29 net 8f7aa3d3c732 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/04 02:31 net 108f9405ce81 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/03 22:24 net 108f9405ce81 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/11/25 20:17 net 9780f535f8e0 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in rt6_find_cached_rt
2025/12/17 14:39 net-next 8f7aa3d3c732 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce general protection fault in rt6_find_cached_rt
* Struck through repros no longer work on HEAD.