From: Renato Westphal <renato@opensourcerouting.org>
Date: Fri, 19 Oct 2018 18:54:05 +0000 (-0300)
Subject: bgpd: fix the "no neighbor A.B.C.D maximum-prefix" command
X-Git-Tag: frr-7.1-dev~253^2~10
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=6282637da16571ea90cfaf658fe092792f7841ed;p=mirror%2Ffrr.git

bgpd: fix the "no neighbor A.B.C.D maximum-prefix" command

The peer->group pointer is set only if the PEER_STATUS_GROUP flag is
set in the peer. Add a protection to prevent a NULL pointer dereference.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
---

diff --git a/bgpd/bgpd.c b/bgpd/bgpd.c
index 9272eae95f..e82f9e1b0d 100644
--- a/bgpd/bgpd.c
+++ b/bgpd/bgpd.c
@@ -6306,9 +6306,6 @@ int peer_maximum_prefix_set(struct peer *peer, afi_t afi, safi_t safi,
 
 int peer_maximum_prefix_unset(struct peer *peer, afi_t afi, safi_t safi)
 {
-	struct peer *member;
-	struct listnode *node, *nnode;
-
 	/* Inherit configuration from peer-group if peer is member. */
 	if (peer_group_active(peer)) {
 		peer_af_flag_inherit(peer, afi, safi, PEER_FLAG_MAX_PREFIX);
@@ -6332,19 +6329,26 @@ int peer_maximum_prefix_unset(struct peer *peer, afi_t afi, safi_t safi)
 	 * Remove flags and configuration from all peer-group members, unless
 	 * they are explicitely overriding peer-group configuration.
 	 */
-	for (ALL_LIST_ELEMENTS(peer->group->peer, node, nnode, member)) {
-		/* Skip peers with overridden configuration. */
-		if (CHECK_FLAG(member->af_flags_override[afi][safi],
-			       PEER_FLAG_MAX_PREFIX))
-			continue;
+	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
+		struct peer *member;
+		struct listnode *node;
 
-		/* Remove flag and configuration on peer-group member. */
-		UNSET_FLAG(member->af_flags[afi][safi], PEER_FLAG_MAX_PREFIX);
-		UNSET_FLAG(member->af_flags[afi][safi],
-			   PEER_FLAG_MAX_PREFIX_WARNING);
-		member->pmax[afi][safi] = 0;
-		member->pmax_threshold[afi][safi] = 0;
-		member->pmax_restart[afi][safi] = 0;
+		for (ALL_LIST_ELEMENTS_RO(peer->group->peer, node, member)) {
+			/* Skip peers with overridden configuration. */
+			if (CHECK_FLAG(member->af_flags_override[afi][safi],
+				       PEER_FLAG_MAX_PREFIX))
+				continue;
+
+			/* Remove flag and configuration on peer-group member.
+			 */
+			UNSET_FLAG(member->af_flags[afi][safi],
+				   PEER_FLAG_MAX_PREFIX);
+			UNSET_FLAG(member->af_flags[afi][safi],
+				   PEER_FLAG_MAX_PREFIX_WARNING);
+			member->pmax[afi][safi] = 0;
+			member->pmax_threshold[afi][safi] = 0;
+			member->pmax_restart[afi][safi] = 0;
+		}
 	}
 
 	return 0;