diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c
index 123cf7e44fd..5dd66dab24d 100644
--- a/sys/netinet/ip_icmp.c
+++ b/sys/netinet/ip_icmp.c
@@ -264,6 +264,7 @@ icmp_error(struct mbuf *n, int type, int code, uint32_t dest, int mtu)
 		if (n->m_len < oiphlen + tcphlen &&
 		    (n = m_pullup(n, oiphlen + tcphlen)) == NULL)
 			goto freeit;
+		oip = mtod(n, struct ip *);
 		icmpelen = max(tcphlen, min(V_icmp_quotelen,
 		    ntohs(oip->ip_len) - oiphlen));
 	} else if (oip->ip_p == IPPROTO_SCTP) {