[IPV4]: Always set fl.proto in ip_route_newports

ip_route_newports uses the struct flowi from the struct rtable returned
by ip_route_connect for the new route lookup and just replaces the port
numbers if they have changed. If an IPsec policy exists which doesn't match
port 0 the struct flowi won't have the proto field set and no xfrm lookup
is done for the changed ports.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/route.h

@@ -170,8 +170,8 @@ static inline int ip_route_connect(struct rtable **rp, u32 dst,
 	return ip_route_output_flow(rp, &fl, sk, 0);
 }
 
-static inline int ip_route_newports(struct rtable **rp, u16 sport, u16 dport,
-				    struct sock *sk)
+static inline int ip_route_newports(struct rtable **rp, u8 protocol,
+				    u16 sport, u16 dport, struct sock *sk)
 {
 	if (sport != (*rp)->fl.fl_ip_sport ||
 	    dport != (*rp)->fl.fl_ip_dport) {
@@ -180,6 +180,7 @@ static inline int ip_route_newports(struct rtable **rp, u16 sport, u16 dport,
 		memcpy(&fl, &(*rp)->fl, sizeof(fl));
 		fl.fl_ip_sport = sport;
 		fl.fl_ip_dport = dport;
+		fl.proto = protocol;
 		ip_rt_put(*rp);
 		*rp = NULL;
 		return ip_route_output_flow(rp, &fl, sk, 0);

net/dccp/ipv4.c

@@ -119,7 +119,8 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (err != 0)
 		goto failure;
 
-	err = ip_route_newports(&rt, inet->sport, inet->dport, sk);
+	err = ip_route_newports(&rt, IPPROTO_DCCP, inet->sport, inet->dport,
+	                        sk);
 	if (err != 0)
 		goto failure;
 

net/ipv4/tcp_ipv4.c

@@ -236,7 +236,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (err)
 		goto failure;
 
-	err = ip_route_newports(&rt, inet->sport, inet->dport, sk);
+	err = ip_route_newports(&rt, IPPROTO_TCP, inet->sport, inet->dport, sk);
 	if (err)
 		goto failure;