syzbot


general protection fault in find_match

Status: premoderation: reported on 2025/05/12 10:56
Reported-by: syzbot+5e982906b6dce78ec6a4@syzkaller.appspotmail.com
First crash: 108d, last: 19d
Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in find_match net 2 C done error 10 2021d 2207d 0/29 closed as invalid on 2020/04/17 19:54
upstream general protection fault in find_match (3) net 2 2 1052d 1095d 0/29 auto-obsoleted due to no activity on 2023/01/16 14:40
upstream general protection fault in find_match (4) net 2 1 736d 732d 0/29 auto-obsoleted due to no activity on 2023/11/20 22:29
upstream general protection fault in find_match (2) net 2 4 1644d 1710d 0/29 auto-closed as invalid on 2021/06/26 04:02
linux-5.15 BUG: unable to handle kernel paging request in find_match 8 5 97d 152d 0/3 upstream: reported on 2025/03/28 21:20
android-5-15 general protection fault in find_match 2 7 45d 142d 0/2 premoderation: reported on 2025/04/08 10:01
upstream general protection fault in find_match (5) net 2 2 444d 444d 26/29 fixed on 2024/07/10 10:07
linux-4.19 general protection fault in find_match 2 C error 1 1438d 2136d 0/1 upstream: reported C repro on 2019/10/23 12:46
android-5-10 general protection fault in find_match 2 45 8d04h 146d 0/2 premoderation: reported on 2025/04/04 19:16
linux-6.1 BUG: unable to handle kernel paging request in find_match 8 18 50d 91d 0/3 upstream: reported on 2025/05/28 21:21

Sample crash report:
EXT4-fs (loop8): mounted filesystem without journal. Quota mode: none.
general protection fault, probably for non-canonical address 0xdffffc000000005b: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000002d8-0x00000000000002df]
CPU: 1 PID: 15043 Comm: syz.8.3977 Not tainted 6.1.145-syzkaller-00002-gc750dc582629 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__in6_dev_get include/net/addrconf.h:355 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:446 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:781
Code: 7c 05 00 00 74 08 48 89 df e8 b5 41 60 fd 48 89 d8 bb d8 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 8b 41 60 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc900021fe8e0 EFLAGS: 00010202
RAX: 000000000000005b RBX: 00000000000002d8 RCX: dffffc0000000000
RDX: ffff888112965100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900021fe998 R08: ffffc900021fecc0 R09: ffffc900021fecd0
R10: 0000000000000000 R11: 1ffff9200043fdba R12: 0000000000000201
R13: 1ffff1102627c544 R14: 0000000000000000 R15: 0000000000000003
FS:  00007f665b6906c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30615ff8 CR3: 000000011b6a5000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rt6_nh_find_match+0xd9/0x140 net/ipv6/route.c:821
 nexthop_for_each_fib6_nh+0x107/0x200 net/ipv4/nexthop.c:1243
 __find_rr_leaf+0x50f/0x900 net/ipv6/route.c:862
 find_rr_leaf net/ipv6/route.c:890 [inline]
 rt6_select net/ipv6/route.c:934 [inline]
 fib6_table_lookup+0x2c1/0x9a0 net/ipv6/route.c:2223
 ip6_pol_route+0x14c/0x1110 net/ipv6/route.c:2259
 ip6_pol_route_output+0x51/0x80 net/ipv6/route.c:2634
 pol_lookup_func include/net/ip6_fib.h:589 [inline]
 fib6_rule_lookup+0x311/0x580 net/ipv6/fib6_rules.c:121
 ip6_route_output_flags_noref+0x283/0x340 net/ipv6/route.c:2666
 ip6_route_output_flags+0x3c/0x200 net/ipv6/route.c:2679
 ip6_route_output include/net/ip6_route.h:98 [inline]
 ip6_update_pmtu+0x1d8/0x300 net/ipv6/route.c:2981
 icmpv6_err+0x124/0x270 net/ipv6/icmp.c:82
 icmpv6_notify+0x30b/0x5d0 net/ipv6/icmp.c:856
 icmpv6_rcv+0x103c/0x1ad0 net/ipv6/icmp.c:-1
 ip6_protocol_deliver_rcu+0xaf7/0x1510 net/ipv6/ip6_input.c:438
 ip6_input_finish net/ipv6/ip6_input.c:483 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip6_input+0x1be/0x370 net/ipv6/ip6_input.c:492
 ip6_mc_input+0x386/0x690 net/ipv6/ip6_input.c:586
 dst_input include/net/dst.h:463 [inline]
 ip6_rcv_finish+0x19e/0x370 net/ipv6/ip6_input.c:79
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ipv6_rcv+0xe9/0x210 net/ipv6/ip6_input.c:310
 __netif_receive_skb_one_core net/core/dev.c:5585 [inline]
 __netif_receive_skb+0xd7/0x2a0 net/core/dev.c:5699
 netif_receive_skb_internal net/core/dev.c:5785 [inline]
 netif_receive_skb+0x98/0x3d0 net/core/dev.c:5844
 tun_rx_batched+0x1b6/0x770 drivers/net/tun.c:1548
 tun_get_user+0x2494/0x3320 drivers/net/tun.c:1998
 tun_chr_write_iter+0x1fb/0x300 drivers/net/tun.c:2044
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5db/0xca0 fs/read_write.c:584
 ksys_write+0x140/0x240 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f665a78d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f665b690000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f665a9b5fa0 RCX: 00007f665a78d69f
RDX: 000000000000006e RSI: 0000200000000140 RDI: 00000000000000c8
RBP: 00007f665a811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000006e R11: 0000000000000293 R12: 0000000000000000
R13: 00007f665a9b6038 R14: 00007f665a9b5fa0 R15: 00007ffff85a2978
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__in6_dev_get include/net/addrconf.h:355 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:446 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:781
Code: 7c 05 00 00 74 08 48 89 df e8 b5 41 60 fd 48 89 d8 bb d8 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 8b 41 60 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc900021fe8e0 EFLAGS: 00010202
RAX: 000000000000005b RBX: 00000000000002d8 RCX: dffffc0000000000
RDX: ffff888112965100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900021fe998 R08: ffffc900021fecc0 R09: ffffc900021fecd0
R10: 0000000000000000 R11: 1ffff9200043fdba R12: 0000000000000201
R13: 1ffff1102627c544 R14: 0000000000000000 R15: 0000000000000003
FS:  00007f665b6906c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30615ff8 CR3: 000000011b6a5000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	7c 05                	jl     0x7
   2:	00 00                	add    %al,(%rax)
   4:	74 08                	je     0xe
   6:	48 89 df             	mov    %rbx,%rdi
   9:	e8 b5 41 60 fd       	call   0xfd6041c3
   e:	48 89 d8             	mov    %rbx,%rax
  11:	bb d8 02 00 00       	mov    $0x2d8,%ebx
  16:	48 03 18             	add    (%rax),%rbx
  19:	48 89 d8             	mov    %rbx,%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:	48 89 df             	mov    %rbx,%rdi
  33:	e8 8b 41 60 fd       	call   0xfd6041c3
  38:	48 8b 1b             	mov    (%rbx),%rbx
  3b:	48 85 db             	test   %rbx,%rbx
  3e:	0f                   	.byte 0xf
  3f:	84                   	.byte 0x84

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/09 17:12 android14-6.1 c750dc582629 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in find_match
2025/07/24 02:53 android14-6.1 96160a0e0aa1 0c1d6ded .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in find_match
2025/06/05 17:45 android14-6.1 d8780220fd00 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in find_match
2025/05/12 10:55 android14-6.1 646380b087a5 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in find_match
* Struck through repros no longer work on HEAD.