inet: remove now unused flag DST_NOPEER

Commit e688a604807647 ("net: introduce DST_NOPEER dst flag") introduced
DST_NOPEER because because of crashes in ipv6_select_ident called from
udp6_ufo_fragment.

Since commit 916e4cf46d0204 ("ipv6: reuse ip6_frag_id from
ip6_ufo_append_data") we don't call ipv6_select_ident any more from
ip6_ufo_append_data, thus this flag lost its purpose and can be removed.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dst.h

@@ -54,10 +54,9 @@ struct dst_entry {
 #define DST_NOHASH		0x0008
 #define DST_NOCACHE		0x0010
 #define DST_NOCOUNT		0x0020
-#define DST_NOPEER		0x0040
-#define DST_FAKE_RTABLE		0x0080
-#define DST_XFRM_TUNNEL		0x0100
-#define DST_XFRM_QUEUE		0x0200
+#define DST_FAKE_RTABLE		0x0040
+#define DST_XFRM_TUNNEL		0x0080
+#define DST_XFRM_QUEUE		0x0100
 
 	unsigned short		pending_confirm;
 

net/bridge/br_netfilter.c

@@ -167,7 +167,7 @@ void br_netfilter_rtable_init(struct net_bridge *br)
 	rt->dst.dev = br->dev;
 	rt->dst.path = &rt->dst;
 	dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
-	rt->dst.flags	= DST_NOXFRM | DST_NOPEER | DST_FAKE_RTABLE;
+	rt->dst.flags	= DST_NOXFRM | DST_FAKE_RTABLE;
 	rt->dst.ops = &fake_dst_ops;
 }
 

net/ipv6/output_core.c

@@ -13,7 +13,7 @@ void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
 	int old, new;
 
 #if IS_ENABLED(CONFIG_IPV6)
-	if (rt && !(rt->dst.flags & DST_NOPEER)) {
+	if (rt) {
 		struct inet_peer *peer;
 		struct net *net;