[UDP]: Reread uh pointer after pskb_trim

The header may have moved when trimming.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index ce6c46034314..fc620a7c1db4 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1215,6 +1215,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[],
 
                 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
                         goto short_packet;
+                uh = skb->h.uh;
 
                 udp4_csum_init(skb, uh);