[SRU bionic PATCH 1/2] ipv6: constify rt6_nexthop()

[Nicolas Dichtel]

BugLink: https://bugs.launchpad.net/bugs/1834465

There is no functional change in this patch, it only prepares the next one.

rt6_nexthop() will be used by ip6_dst_lookup_neigh(), which uses const
variables.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Reported-by: kbuild test robot <lkp at intel.com>
Acked-by: Nick Desaulniers <ndesaulniers at google.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit 9b1c1ef13b35fa35051b635ca9fbda39fe6bbc70)
Signed-off-by: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
---
 drivers/net/vrf.c       | 2 +-
 include/net/ip6_route.h | 4 ++--
 net/bluetooth/6lowpan.c | 4 ++--
 net/ipv6/ip6_output.c   | 2 +-
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index ac40924fe437..f24f135dd537 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -351,8 +351,8 @@ static int vrf_finish_output6(struct net *net, struct sock *sk,
 {
 	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *dev = dst->dev;
+	const struct in6_addr *nexthop;
 	struct neighbour *neigh;
-	struct in6_addr *nexthop;
 	int ret;
 
 	nf_reset(skb);
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 5c9732fdbecf..ba85be3f4f71 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -242,8 +242,8 @@ static inline bool ip6_sk_ignore_df(const struct sock *sk)
 	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
 }
 
-static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
-					   struct in6_addr *daddr)
+static inline const struct in6_addr *rt6_nexthop(const struct rt6_info *rt,
+						 const struct in6_addr *daddr)
 {
 	if (rt->rt6i_flags & RTF_GATEWAY)
 		return &rt->rt6i_gateway;
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 4e2576fc0c59..a28e3fdb3e5b 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -167,10 +167,10 @@ static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_btle_dev *dev,
 						  struct in6_addr *daddr,
 						  struct sk_buff *skb)
 {
-	struct lowpan_peer *peer;
-	struct in6_addr *nexthop;
 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
 	int count = atomic_read(&dev->peer_count);
+	const struct in6_addr *nexthop;
+	struct lowpan_peer *peer;
 
 	BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
 
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 7ca8264cbdf9..11789f2bab90 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -63,8 +63,8 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 {
 	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *dev = dst->dev;
+	const struct in6_addr *nexthop;
 	struct neighbour *neigh;
-	struct in6_addr *nexthop;
 	int ret;
 
 	if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
-- 
2.21.0