1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 11d1b2080a16..fb47c8f0cd86 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1816,15 +1816,15 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
 
 static unsigned int ipv4_mtu(const struct dst_entry *dst)
 {
+        const struct rtable *rt = (const struct rtable *) dst;
         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 
-        if (mtu)
+        if (mtu && rt_is_output_route(rt))
                 return mtu;
 
         mtu = dst->dev->mtu;
 
         if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
-                const struct rtable *rt = (const struct rtable *) dst;
 
                 if (rt->rt_gateway != rt->rt_dst && mtu > 576)
                         mtu = 576;