diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 25501aa69293..0d1848204289 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1806,6 +1806,7 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 	if (mcopy != NULL) {
 		mcopy->m_len = imin((ip->ip_hl << 2) + 8,
 		    (int)ip->ip_len);
+		mcopy->m_pkthdr.len = mcopy->m_len;
 		m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
 	}