Phonet: refuse to send bigger than MTU packets

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c
index defeb7a0d50..7ab30f668b5 100644
--- a/net/phonet/af_phonet.c
+++ b/net/phonet/af_phonet.c
@@ -144,8 +144,8 @@ static int pn_send(struct sk_buff *skb, struct net_device *dev,
         struct phonethdr *ph;
         int err;
 
-        if (skb->len + 2 > 0xffff) {
-                /* Phonet length field would overflow */
+        if (skb->len + 2 > 0xffff /* Phonet length field limit */ ||
+            skb->len + sizeof(struct phonethdr) > dev->mtu) {
                 err = -EMSGSIZE;
                 goto drop;
         }