Merge 4.1-rc4 into staging-next

We want the fixes in here for testing and merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 31 insertions, 8 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 7fde1f265c90..c21777565c58 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -886,22 +886,45 @@ static int ip6_dst_lookup_tail(struct sock *sk,
 #endif
 	int err;
 
-	if (!*dst)
-		*dst = ip6_route_output(net, sk, fl6);
-
-	err = (*dst)->error;
-	if (err)
-		goto out_err_release;
+	/* The correct way to handle this would be to do
+	 * ip6_route_get_saddr, and then ip6_route_output; however,
+	 * the route-specific preferred source forces the
+	 * ip6_route_output call _before_ ip6_route_get_saddr.
+	 *
+	 * In source specific routing (no src=any default route),
+	 * ip6_route_output will fail given src=any saddr, though, so
+	 * that's why we try it again later.
+	 */
+	if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) {
+		struct rt6_info *rt;
+		bool had_dst = *dst != NULL;
 
-	if (ipv6_addr_any(&fl6->saddr)) {
-		struct rt6_info *rt = (struct rt6_info *) *dst;
+		if (!had_dst)
+			*dst = ip6_route_output(net, sk, fl6);
+		rt = (*dst)->error ? NULL : (struct rt6_info *)*dst;
 		err = ip6_route_get_saddr(net, rt, &fl6->daddr,
 					  sk ? inet6_sk(sk)->srcprefs : 0,
 					  &fl6->saddr);
 		if (err)
 			goto out_err_release;
+
+		/* If we had an erroneous initial result, pretend it
+		 * never existed and let the SA-enabled version take
+		 * over.
+		 */
+		if (!had_dst && (*dst)->error) {
+			dst_release(*dst);
+			*dst = NULL;
+		}
 	}
 
+	if (!*dst)
+		*dst = ip6_route_output(net, sk, fl6);
+
+	err = (*dst)->error;
+	if (err)
+		goto out_err_release;
+
 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
 	/*
 	 * Here if the dst entry we've looked up