ipv6: ip6_sk_dst_check() must not assume ipv6 dst

[~andy/linux] / net / ipv6 / ip6_output.c

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 95703ba2c084de31c8de3c41d830bb789f2f416e..d5d20cde8d92808387e171fb25b2fa701a06f275 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -821,11 +821,17 @@ static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
                                          const struct flowi6 *fl6)
 {
        struct ipv6_pinfo *np = inet6_sk(sk);
-       struct rt6_info *rt = (struct rt6_info *)dst;
+       struct rt6_info *rt;
 
        if (!dst)
                goto out;
 
+       if (dst->ops->family != AF_INET6) {
+               dst_release(dst);
+               return NULL;
+       }
+
+       rt = (struct rt6_info *)dst;
        /* Yes, checking route validity in not connected
         * case is not very simple. Take into account,
         * that we do not support routing by source, TOS,