ipv6: fix inet6_csk_xmit()

We should provide to inet6_csk_route_socket a struct flowi6 pointer,
so that net6_csk_xmit() works correctly instead of sending garbage.

Also add some consts

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 19 deletions

diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index 4a0c4d2d8b05..0251a6005be8 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -171,7 +171,8 @@ EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
 
 static inline
 void __inet6_csk_dst_store(struct sock *sk, struct dst_entry *dst,
-                           struct in6_addr *daddr, struct in6_addr *saddr)
+                           const struct in6_addr *daddr,
+                           const struct in6_addr *saddr)
 {
         __ip6_dst_store(sk, dst, daddr, saddr);
 
@@ -203,31 +204,31 @@ struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie)
         return dst;
 }
 
-static struct dst_entry *inet6_csk_route_socket(struct sock *sk)
+static struct dst_entry *inet6_csk_route_socket(struct sock *sk,
+                                                struct flowi6 *fl6)
 {
         struct inet_sock *inet = inet_sk(sk);
         struct ipv6_pinfo *np = inet6_sk(sk);
         struct in6_addr *final_p, final;
         struct dst_entry *dst;
-        struct flowi6 fl6;
 
-        memset(&fl6, 0, sizeof(fl6));
-        fl6.flowi6_proto = sk->sk_protocol;
-        fl6.daddr = np->daddr;
-        fl6.saddr = np->saddr;
-        fl6.flowlabel = np->flow_label;
-        IP6_ECN_flow_xmit(sk, fl6.flowlabel);
-        fl6.flowi6_oif = sk->sk_bound_dev_if;
-        fl6.flowi6_mark = sk->sk_mark;
-        fl6.fl6_sport = inet->inet_sport;
-        fl6.fl6_dport = inet->inet_dport;
-        security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+        memset(fl6, 0, sizeof(*fl6));
+        fl6->flowi6_proto = sk->sk_protocol;
+        fl6->daddr = np->daddr;
+        fl6->saddr = np->saddr;
+        fl6->flowlabel = np->flow_label;
+        IP6_ECN_flow_xmit(sk, fl6->flowlabel);
+        fl6->flowi6_oif = sk->sk_bound_dev_if;
+        fl6->flowi6_mark = sk->sk_mark;
+        fl6->fl6_sport = inet->inet_sport;
+        fl6->fl6_dport = inet->inet_dport;
+        security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
 
-        final_p = fl6_update_dst(&fl6, np->opt, &final);
+        final_p = fl6_update_dst(fl6, np->opt, &final);
 
         dst = __inet6_csk_dst_check(sk, np->dst_cookie);
         if (!dst) {
-                dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
+                dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
 
                 if (!IS_ERR(dst))
                         __inet6_csk_dst_store(sk, dst, NULL, NULL);
@@ -243,7 +244,7 @@ int inet6_csk_xmit(struct sk_buff *skb, struct flowi *fl_unused)
         struct dst_entry *dst;
         int res;
 
-        dst = inet6_csk_route_socket(sk);
+        dst = inet6_csk_route_socket(sk, &fl6);
         if (IS_ERR(dst)) {
                 sk->sk_err_soft = -PTR_ERR(dst);
                 sk->sk_route_caps = 0;
@@ -265,12 +266,13 @@ EXPORT_SYMBOL_GPL(inet6_csk_xmit);
 
 struct dst_entry *inet6_csk_update_pmtu(struct sock *sk, u32 mtu)
 {
-        struct dst_entry *dst = inet6_csk_route_socket(sk);
+        struct flowi6 fl6;
+        struct dst_entry *dst = inet6_csk_route_socket(sk, &fl6);
 
         if (IS_ERR(dst))
                 return NULL;
         dst->ops->update_pmtu(dst, sk, NULL, mtu);
 
-        return inet6_csk_route_socket(sk);
+        return inet6_csk_route_socket(sk, &fl6);
 }
 EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu);