From 6e081509db323a8352d22e9f4793f7837634abf7 Mon Sep 17 00:00:00 2001
From: "Andrey V. Elsukov" <ae@FreeBSD.org>
Date: Thu, 28 Jun 2018 11:39:27 +0000
Subject: [PATCH] Add NULL pointer check.

encap_lookup_t method can be invoked by IP encap subsytem even if none
of gif/gre/me interfaces are exist. Hash tables are allocated on demand,
when first interface is created. So, make NULL pointer check before
doing access to hash table.

PR:		229378
---
 sys/net/if_me.c        | 3 +++
 sys/netinet/in_gif.c   | 3 +++
 sys/netinet/ip_gre.c   | 3 +++
 sys/netinet6/in6_gif.c | 3 +++
 sys/netinet6/ip6_gre.c | 3 +++
 5 files changed, 15 insertions(+)

diff --git a/sys/net/if_me.c b/sys/net/if_me.c
index 024d392cc3e9..9ba44b0cb215 100644
--- a/sys/net/if_me.c
+++ b/sys/net/if_me.c
@@ -312,6 +312,9 @@ me_lookup(const struct mbuf *m, int off, int proto, void **arg)
 	const struct ip *ip;
 	struct me_softc *sc;
 
+	if (V_me_hashtbl == NULL)
+		return (0);
+
 	MPASS(in_epoch());
 	ip = mtod(m, const struct ip *);
 	CK_LIST_FOREACH(sc, &ME_HASH(ip->ip_dst.s_addr,
diff --git a/sys/netinet/in_gif.c b/sys/netinet/in_gif.c
index 5f4af01b199a..06b567400297 100644
--- a/sys/netinet/in_gif.c
+++ b/sys/netinet/in_gif.c
@@ -289,6 +289,9 @@ in_gif_lookup(const struct mbuf *m, int off, int proto, void **arg)
 	struct gif_softc *sc;
 	int ret;
 
+	if (V_ipv4_hashtbl == NULL)
+		return (0);
+
 	MPASS(in_epoch());
 	ip = mtod(m, const struct ip *);
 	/*
diff --git a/sys/netinet/ip_gre.c b/sys/netinet/ip_gre.c
index ee36a0e18fce..9ee09f1e28d5 100644
--- a/sys/netinet/ip_gre.c
+++ b/sys/netinet/ip_gre.c
@@ -115,6 +115,9 @@ in_gre_lookup(const struct mbuf *m, int off, int proto, void **arg)
 	const struct ip *ip;
 	struct gre_softc *sc;
 
+	if (V_ipv4_hashtbl == NULL)
+		return (0);
+
 	MPASS(in_epoch());
 	ip = mtod(m, const struct ip *);
 	CK_LIST_FOREACH(sc, &GRE_HASH(ip->ip_dst.s_addr,
diff --git a/sys/netinet6/in6_gif.c b/sys/netinet6/in6_gif.c
index 1834660ce1ee..cbcbfae0abc9 100644
--- a/sys/netinet6/in6_gif.c
+++ b/sys/netinet6/in6_gif.c
@@ -309,6 +309,9 @@ in6_gif_lookup(const struct mbuf *m, int off, int proto, void **arg)
 	struct gif_softc *sc;
 	int ret;
 
+	if (V_ipv6_hashtbl == NULL)
+		return (0);
+
 	MPASS(in_epoch());
 	/*
 	 * NOTE: it is safe to iterate without any locking here, because softc
diff --git a/sys/netinet6/ip6_gre.c b/sys/netinet6/ip6_gre.c
index b3c419ce6e6a..bb786c9416e8 100644
--- a/sys/netinet6/ip6_gre.c
+++ b/sys/netinet6/ip6_gre.c
@@ -107,6 +107,9 @@ in6_gre_lookup(const struct mbuf *m, int off, int proto, void **arg)
 	const struct ip6_hdr *ip6;
 	struct gre_softc *sc;
 
+	if (V_ipv6_hashtbl == NULL)
+		return (0);
+
 	MPASS(in_epoch());
 	ip6 = mtod(m, const struct ip6_hdr *);
 	CK_LIST_FOREACH(sc, &GRE_HASH(&ip6->ip6_dst, &ip6->ip6_src), chain) {