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general protection fault in nexthop_is_blackhole (2)

Status: closed as invalid on 2025/04/08 14:38
Subsystems: net
[Documentation on labels]
First crash: 105d, last: 105d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in nexthop_is_blackhole net C done done 1 1767d 1764d 15/29 fixed on 2020/11/16 12:12

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
CPU: 0 UID: 0 PID: 5318 Comm: kworker/0:5 Not tainted 6.14.0-rc6-syzkaller-00016-g0fed89a961ea #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: mld mld_dad_work
RIP: 0010:nexthop_is_blackhole+0x23/0x2a0 include/net/nexthop.h:370
Code: 90 90 90 90 90 90 90 55 41 57 41 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df e8 e8 8c 1c f7 4c 8d 73 66 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 1d 02 00 00 41 0f b6 2e 31 ff 89 ee e8
RSP: 0018:ffffc90000007038 EFLAGS: 00010202
RAX: 000000000000000d RBX: 0000000000000003 RCX: ffff888000d4c880
RDX: 0000000000000100 RSI: 1ffff92000000e25 RDI: 0000000000000003
RBP: ffffc900000071d8 R08: ffffffff8aa69245 R09: 0000000000000036
R10: ffffc90000007300 R11: fffff52000000e2e R12: ffff88804442f400
R13: 1ffff11008885e8c R14: 0000000000000069 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005619d3bd7098 CR3: 00000000126e4000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __find_rr_leaf+0x559/0x8e0 net/ipv6/route.c:821
 find_rr_leaf net/ipv6/route.c:865 [inline]
 rt6_select net/ipv6/route.c:900 [inline]
 fib6_table_lookup+0x56f/0xbb0 net/ipv6/route.c:2195
 ip6_pol_route+0x273/0x15d0 net/ipv6/route.c:2231
 pol_lookup_func include/net/ip6_fib.h:616 [inline]
 fib6_rule_lookup+0x58c/0x790 net/ipv6/fib6_rules.c:119
 ip6_route_input_lookup net/ipv6/route.c:2300 [inline]
 ip6_route_input+0x859/0xd90 net/ipv6/route.c:2596
 ip6_rcv_finish+0x140/0x3d0 net/ipv6/ip6_input.c:77
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5893 [inline]
 __netif_receive_skb+0x1ea/0x650 net/core/dev.c:6006
 process_backlog+0x662/0x15b0 net/core/dev.c:6354
 __napi_poll+0xcb/0x490 net/core/dev.c:7188
 napi_poll net/core/dev.c:7257 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7379
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 do_softirq+0x11b/0x1e0 kernel/softirq.c:462
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]
 __dev_queue_xmit+0x1775/0x3f50 net/core/dev.c:4676
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip6_finish_output2+0x127d/0x17c0 net/ipv6/ip6_output.c:141
 ip6_finish_output+0x41e/0x840 net/ipv6/ip6_output.c:226
 NF_HOOK+0x9e/0x430 include/linux/netfilter.h:314
 mld_sendpack+0x843/0xdb0 net/ipv6/mcast.c:1868
 mld_dad_work+0x44/0x500 net/ipv6/mcast.c:2308
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:nexthop_is_blackhole+0x23/0x2a0 include/net/nexthop.h:370
Code: 90 90 90 90 90 90 90 55 41 57 41 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df e8 e8 8c 1c f7 4c 8d 73 66 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 1d 02 00 00 41 0f b6 2e 31 ff 89 ee e8
RSP: 0018:ffffc90000007038 EFLAGS: 00010202
RAX: 000000000000000d RBX: 0000000000000003 RCX: ffff888000d4c880
RDX: 0000000000000100 RSI: 1ffff92000000e25 RDI: 0000000000000003
RBP: ffffc900000071d8 R08: ffffffff8aa69245 R09: 0000000000000036
R10: ffffc90000007300 R11: fffff52000000e2e R12: ffff88804442f400
R13: 1ffff11008885e8c R14: 0000000000000069 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005619d3bd7098 CR3: 00000000126e4000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	55                   	push   %rbp
   8:	41 57                	push   %r15
   a:	41 56                	push   %r14
   c:	53                   	push   %rbx
   d:	48 89 fb             	mov    %rdi,%rbx
  10:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
  17:	fc ff df
  1a:	e8 e8 8c 1c f7       	call   0xf71c8d07
  1f:	4c 8d 73 66          	lea    0x66(%rbx),%r14
  23:	4c 89 f0             	mov    %r14,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 38       	movzbl (%rax,%r15,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 1d 02 00 00    	jne    0x254
  37:	41 0f b6 2e          	movzbl (%r14),%ebp
  3b:	31 ff                	xor    %edi,%edi
  3d:	89 ee                	mov    %ebp,%esi
  3f:	e8                   	.byte 0xe8

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/12 17:39 upstream 0fed89a961ea ee70e6db .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in nexthop_is_blackhole
* Struck through repros no longer work on HEAD.