syzbot


general protection fault in find_match

Status: premoderation: reported on 2025/04/08 10:01
Reported-by: syzbot+fdf88e02000ad656bb67@syzkaller.appspotmail.com
First crash: 92d, last: 5d00h
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 1970d 2157d 0/29 closed as invalid on 2020/04/17 19:54
upstream general protection fault in find_match (3) net 2 2 1002d 1045d 0/29 auto-obsoleted due to no activity on 2023/01/16 14:40
android-6-1 general protection fault in find_match 2 2 33d 58d 0/2 premoderation: reported on 2025/05/12 10:56
upstream general protection fault in find_match (4) net 2 1 686d 682d 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 1594d 1660d 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 47d 102d 0/3 upstream: reported on 2025/03/28 21:20
upstream general protection fault in find_match (5) net 2 2 394d 394d 26/29 fixed on 2024/07/10 10:07
linux-4.19 general protection fault in find_match 2 C error 1 1388d 2086d 0/1 upstream: reported C repro on 2019/10/23 12:46
android-5-10 general protection fault in find_match 2 40 33d 95d 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 18h28m 41d 0/3 upstream: reported on 2025/05/28 21:21

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000005e: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000002f0-0x00000000000002f7]
CPU: 1 PID: 19391 Comm: syz.6.7841 Not tainted 5.15.185-syzkaller-00178-g5cf73bface18 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__in6_dev_get include/net/addrconf.h:341 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:432 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:744
Code: 7c 05 00 00 74 08 48 89 df e8 45 30 87 fd 48 89 d8 bb f0 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 1b 30 87 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc90000ec6f40 EFLAGS: 00010202
RAX: 000000000000005e RBX: 00000000000002f0 RCX: dffffc0000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000ec6ff8 R08: ffffc90000ec7320 R09: ffffc90000ec7330
R10: fffff520001d8e86 R11: 1ffff920001d8e82 R12: 0000000000000201
R13: 1ffff11027206a04 R14: 0000000000000000 R15: 0000000000000003
FS:  00007fc9cf26e6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc9cf26df98 CR3: 0000000118f37000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000000032e7 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rt6_nh_find_match+0xd9/0x140 net/ipv6/route.c:784
 nexthop_for_each_fib6_nh+0xf6/0x1e0 net/ipv4/nexthop.c:1242
 __find_rr_leaf+0x50f/0x900 net/ipv6/route.c:825
 find_rr_leaf net/ipv6/route.c:853 [inline]
 rt6_select net/ipv6/route.c:897 [inline]
 fib6_table_lookup+0x2f4/0x9f0 net/ipv6/route.c:2189
 ip6_pol_route+0x145/0x1110 net/ipv6/route.c:2225
 ip6_pol_route_output+0x51/0x80 net/ipv6/route.c:2601
 pol_lookup_func include/net/ip6_fib.h:592 [inline]
 fib6_rule_lookup+0x2ef/0x560 net/ipv6/fib6_rules.c:120
 ip6_route_output_flags_noref+0x283/0x340 net/ipv6/route.c:2633
 ip6_route_output_flags+0x3c/0x200 net/ipv6/route.c:2646
 ip6_route_output include/net/ip6_route.h:98 [inline]
 ip6_dst_lookup_tail+0x139/0x1370 net/ipv6/ip6_output.c:1102
 ip6_dst_lookup_flow net/ipv6/ip6_output.c:1232 [inline]
 ip6_sk_dst_lookup_flow+0x56e/0x820 net/ipv6/ip6_output.c:1270
 udpv6_sendmsg+0x17d7/0x2670 net/ipv6/udp.c:1561
 inet6_sendmsg+0xa5/0xc0 net/ipv6/af_inet6.c:660
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 __sys_sendto+0x423/0x580 net/socket.c:2063
 __do_sys_sendto net/socket.c:2075 [inline]
 __se_sys_sendto net/socket.c:2071 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2071
 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc9d0c26929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc9cf26e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc9d0e4e080 RCX: 00007fc9d0c26929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fc9d0ca8b39 R08: 0000200000000300 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fc9d0e4e080 R15: 00007fff8a4f1398
 </TASK>
Modules linked in:
---[ end trace cb42717fad4a0cad ]---
RIP: 0010:__in6_dev_get include/net/addrconf.h:341 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:432 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:744
Code: 7c 05 00 00 74 08 48 89 df e8 45 30 87 fd 48 89 d8 bb f0 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 1b 30 87 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc90000ec6f40 EFLAGS: 00010202
RAX: 000000000000005e RBX: 00000000000002f0 RCX: dffffc0000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000ec6ff8 R08: ffffc90000ec7320 R09: ffffc90000ec7330
R10: fffff520001d8e86 R11: 1ffff920001d8e82 R12: 0000000000000201
R13: 1ffff11027206a04 R14: 0000000000000000 R15: 0000000000000003
FS:  00007fc9cf26e6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33e18ff8 CR3: 0000000118f37000 CR4: 00000000003506b0
----------------
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 45 30 87 fd       	call   0xfd873053
   e:	48 89 d8             	mov    %rbx,%rax
  11:	bb f0 02 00 00       	mov    $0x2f0,%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 1b 30 87 fd       	call   0xfd873053
  38:	48 8b 1b             	mov    (%rbx),%rbx
  3b:	48 85 db             	test   %rbx,%rbx
  3e:	0f                   	.byte 0xf
  3f:	84                   	.byte 0x84

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/04 14:47 android13-5.15-lts 5cf73bface18 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/07/03 12:15 android13-5.15-lts 79bd7c447241 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/07/03 12:15 android13-5.15-lts 79bd7c447241 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/05/01 13:09 android13-5.15-lts 88c4075c39ed 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/04/17 03:51 android13-5.15-lts 8034ec1338e8 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/04/08 10:00 android13-5.15-lts 5e1b899f19c3 a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
* Struck through repros no longer work on HEAD.