Index: sys/netinet/in_gif.c
===================================================================
RCS file: /cvsroot/src/sys/netinet/in_gif.c,v
retrieving revision 1.75
diff -p -u -r1.75 in_gif.c
--- sys/netinet/in_gif.c	26 Jan 2016 06:00:10 -0000	1.75
+++ sys/netinet/in_gif.c	3 Feb 2016 22:13:47 -0000
@@ -200,6 +200,11 @@ in_gif_input(struct mbuf *m, int off, in
 	int af;
 	u_int8_t otos;
 
+	KASSERT(IP_HDR_ALIGNED_P(mtod(m, void *)));
+	KASSERT(IP_HDR_ALIGNED_P(off));
+	KASSERT(IP6_HDR_ALIGNED_P(off));
+	KASSERT(TCP_HDR_ALIGNED_P(off));
+	KASSERT(UDP_HDR_ALIGNED_P(off));
 	ip = mtod(m, const struct ip *);
 
 	gifp = (struct ifnet *)encap_getarg(m);
@@ -226,6 +231,7 @@ in_gif_input(struct mbuf *m, int off, in
 #endif
 	otos = ip->ip_tos;
 	m_adj(m, off);
+	KASSERT(IP_HDR_ALIGNED_P(mtod(m, void *)));
 
 	switch (proto) {
 #ifdef INET
@@ -237,6 +243,7 @@ in_gif_input(struct mbuf *m, int off, in
 			if ((m = m_pullup(m, sizeof(*xip))) == NULL)
 				return;
 		}
+		KASSERT(IP_HDR_ALIGNED_P(mtod(m, void *)));
 		xip = mtod(m, struct ip *);
 		if (gifp->if_flags & IFF_LINK1)
 			ip_ecn_egress(ECN_ALLOWED, &otos, &xip->ip_tos);
@@ -255,6 +262,7 @@ in_gif_input(struct mbuf *m, int off, in
 			if ((m = m_pullup(m, sizeof(*ip6))) == NULL)
 				return;
 		}
+		KASSERT(IP6_HDR_ALIGNED_P(mtod(m, void *)));
 		ip6 = mtod(m, struct ip6_hdr *);
 		itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
 		if (gifp->if_flags & IFF_LINK1)