diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index 750b06a..cf73cc7 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -84,6 +84,14 @@ static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
 	*dataoff = nhoff + (iph->ihl << 2);
 	*protonum = iph->protocol;
 
+	/* Check bogus IP headers */
+	if (*dataoff > skb->len) {
+		pr_debug("nf_conntrack_ipv4: bogus IPv4 packet: "
+			 "nhoff %u, ihl %u, skblen %u\n",
+			 nhoff, iph->ihl << 2, skb->len);
+		return -NF_ACCEPT;
+	}
+
 	return NF_ACCEPT;
 }