netdev - Re: [PATCH net] ipv6: no need to return rt->dst.error if it is not null entry.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 20 Jul 2017 23:23:52 +0800
From:   Hangbin Liu <liuhangbin@...il.com>
To:     network dev <netdev@...r.kernel.org>
Cc:     Roopa Prabhu <roopa@...ulusnetworks.com>,
        WANG Cong <xiyou.wangcong@...il.com>,
        Hangbin Liu <liuhangbin@...il.com>
Subject: Re: [PATCH net] ipv6: no need to return rt->dst.error if it is not
 null entry.

2017-07-20 23:06 GMT+08:00 Hangbin Liu <liuhangbin@...il.com>:
>> +++ b/net/ipv6/route.c
>> @@ -3637,12 +3637,6 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
>>                 dst = ip6_route_lookup(net, &fl6, 0);
>>
>>         rt = container_of(dst, struct rt6_info, dst);
>> -       if (rt->dst.error) {
>> -               err = rt->dst.error;
>> -               ip6_rt_put(rt);
>> -               goto errout;
>> -       }
>
> hmm... or instead of remove this check, should we check all the entry? Like
> if ((rt->dst.error && rt != net->ipv6.ip6_null_entry && rt !=
                                                    ^^ mistake here
> net->ipv6.ip6_blk_hole_entry) ||
>      rt == net->ipv6.ip6_null_entry )

Sorry,  there should be no need to check ip6_null_entry since the
error is already
-ENETUNREACH. So how about

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 4d30c96..c290aa4 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -3637,13 +3637,8 @@ static int inet6_rtm_getroute(struct sk_buff
*in_skb, struct nlmsghdr *nlh,
                dst = ip6_route_lookup(net, &fl6, 0);

        rt = container_of(dst, struct rt6_info, dst);
-       if (rt->dst.error) {
-               err = rt->dst.error;
-               ip6_rt_put(rt);
-               goto errout;
-       }
-
-       if (rt == net->ipv6.ip6_null_entry) {
+       if (rt->dst.error && rt != net->ipv6.ip6_prohibit_entry &&
+           rt != net->ipv6.ip6_blk_hole_entry) {
                err = rt->dst.error;
                ip6_rt_put(rt);
                goto errout;

Thanks
Hangbin