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general protection fault in ip6_pol_route (4)

Status: closed as invalid on 2026/04/08 13:13
Subsystems: net
[Documentation on labels]
First crash: 68d, last: 53d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
b5834996-849b-46f7-8b6d-733b9a5927b1 repro general protection fault in ip6_pol_route (4) 2026/03/06 19:41 2026/03/06 19:41 2026/03/06 19:52 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in ip6_pol_route (2) net 19 C done unreliable 9 1441d 1877d 0/29 auto-obsoleted due to no activity on 2022/09/19 15:39
android-6-12 general protection fault in ip6_pol_route 2 1 152d 152d 0/1 auto-obsoleted due to no activity on 2026/02/08 08:13
upstream general protection fault in ip6_pol_route (2) net 8 15 654d 661d 0/29 auto-obsoleted due to no activity on 2024/08/28 04:33
android-6-1 general protection fault in ip6_pol_route 2 1 29d 29d 0/2 premoderation: reported on 2026/03/12 19:09
upstream general protection fault in ip6_pol_route net 8 73 662d 700d 26/29 fixed on 2024/06/18 11:11
upstream general protection fault in ip6_pol_route (3) net 8 syz error 25 304d 431d 0/29 auto-obsoleted due to no activity on 2025/09/19 08:31
linux-5.15 KASAN: use-after-free Read in ip6_pol_route 19 1 746d 746d 0/3 auto-obsoleted due to no activity on 2024/07/04 16:14
upstream Internal error in ip6_pol_route net 2 2 882d 906d 0/29 auto-obsoleted due to no activity on 2024/02/18 23:43

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 02/12/2026
RIP: 0010:fib6_nh_get_excptn_bucket net/ipv6/route.c:1673 [inline]
RIP: 0010:rt6_find_cached_rt net/ipv6/route.c:1871 [inline]
RIP: 0010:ip6_pol_route+0x2e7/0x13d0 net/ipv6/route.c:2289
Code: e8 de 02 73 f7 85 db 4d 0f 44 f7 48 8d 5c 24 38 4c 8b 64 24 70 49 83 c4 60 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 e7 e8 ab 06 dd f7 4d 8b 3c 24 e8 62 4e 59
RSP: 0018:ffffc90000007460 EFLAGS: 00010206
RAX: 000000000000000c RBX: ffffc90000007498 RCX: dffffc0000000000
RDX: ffffffff8e494ec0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007570 R08: ffff888033885133 R09: 1ffff11006710a26
R10: dffffc0000000000 R11: ffffed1006710a27 R12: 0000000000000060
R13: ffffc900000079a8 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812546f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000057eff8 CR3: 000000005a4b4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x36b/0x730 net/ipv6/fib6_rules.c:125
 ip6_route_output_flags_noref net/ipv6/route.c:2697 [inline]
 ip6_route_output_flags+0x364/0x5d0 net/ipv6/route.c:2709
 ip6_dst_lookup_tail+0x2ae/0x15a0 net/ipv6/ip6_output.c:1156
 ip6_dst_lookup_flow+0x47/0xe0 net/ipv6/ip6_output.c:1259
 tipc_udp_xmit+0x360/0xc10 net/tipc/udp_media.c:210
 tipc_udp_send_msg+0x27f/0x3f0 net/tipc/udp_media.c:271
 tipc_bearer_xmit_skb+0x2b3/0x400 net/tipc/bearer.c:575
 tipc_disc_timeout+0x595/0x6f0 net/tipc/discover.c:338
 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
 handle_softirqs+0x22a/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/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+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 7e 6e 02 c3 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 43 8d 1d 00 fb f4 <e9> 7c ea 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000246
RAX: 00000000020c15bd RBX: ffffffff819a779d RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8deed5ed RDI: ffffffff8c279800
RBP: ffffffff8e407eb0 R08: ffff8880b863395b R09: 1ffff110170c672b
R10: dffffc0000000000 R11: ffffed10170c672c R12: ffffffff90114db0
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1bd/0x500 kernel/sched/idle.c:332
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
 rest_init+0x2de/0x300 init/main.c:760
 start_kernel+0x385/0x3d0 init/main.c:1210
 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 net/ipv6/route.c:1871 [inline]
RIP: 0010:ip6_pol_route+0x2e7/0x13d0 net/ipv6/route.c:2289
Code: e8 de 02 73 f7 85 db 4d 0f 44 f7 48 8d 5c 24 38 4c 8b 64 24 70 49 83 c4 60 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 e7 e8 ab 06 dd f7 4d 8b 3c 24 e8 62 4e 59
RSP: 0018:ffffc90000007460 EFLAGS: 00010206
RAX: 000000000000000c RBX: ffffc90000007498 RCX: dffffc0000000000
RDX: ffffffff8e494ec0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007570 R08: ffff888033885133 R09: 1ffff11006710a26
R10: dffffc0000000000 R11: ffffed1006710a27 R12: 0000000000000060
R13: ffffc900000079a8 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812546f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000057eff8 CR3: 000000005a4b4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	e8 de 02 73 f7       	call   0xf77302e3
   5:	85 db                	test   %ebx,%ebx
   7:	4d 0f 44 f7          	cmove  %r15,%r14
   b:	48 8d 5c 24 38       	lea    0x38(%rsp),%rbx
  10:	4c 8b 64 24 70       	mov    0x70(%rsp),%r12
  15:	49 83 c4 60          	add    $0x60,%r12
  19:	4c 89 e0             	mov    %r12,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 e7             	mov    %r12,%rdi
  33:	e8 ab 06 dd f7       	call   0xf7dd06e3
  38:	4d 8b 3c 24          	mov    (%r12),%r15
  3c:	e8                   	.byte 0xe8
  3d:	62                   	.byte 0x62
  3e:	4e 59                	rex.WRX pop %rcx

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/17 00:01 upstream 0f2acd3148e0 5d52cba5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce general protection fault in ip6_pol_route
2026/02/17 16:28 net 22069735ff6d e439b951 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in ip6_pol_route
2026/02/02 09:03 linux-next 4c87cdd03284 018ebef2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ip6_pol_route
* Struck through repros no longer work on HEAD.