From: Josh Cox <josh.cox@pureport.com>
Date: Tue, 5 May 2020 17:09:14 +0000 (-0400)
Subject: bgpd: Check to ensure community attributes exist before freeing them
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=f7a00fd67f79ed7c1fa4bbade99a737a1dee5707;p=mirror%2Ffrr.git

bgpd: Check to ensure community attributes exist before freeing them

Community attributes might have been removed by an inbound route map, so we
should check to ensure they still exist before trying to free them.
This fixes a segfault described in issue #6345.

Signed-off-by: Josh Cox <josh.cox@pureport.com>
---

diff --git a/bgpd/bgp_community.c b/bgpd/bgp_community.c
index 22d61f702d..5a2f35f2c7 100644
--- a/bgpd/bgp_community.c
+++ b/bgpd/bgp_community.c
@@ -40,6 +40,9 @@ static struct community *community_new(void)
 /* Free communities value.  */
 void community_free(struct community **com)
 {
+	if (!(*com))
+		return;
+
 	XFREE(MTYPE_COMMUNITY_VAL, (*com)->val);
 	XFREE(MTYPE_COMMUNITY_STR, (*com)->str);
 
diff --git a/bgpd/bgp_ecommunity.c b/bgpd/bgp_ecommunity.c
index b75676e86e..f4ec09b8a1 100644
--- a/bgpd/bgp_ecommunity.c
+++ b/bgpd/bgp_ecommunity.c
@@ -59,6 +59,9 @@ void ecommunity_strfree(char **s)
 /* Allocate ecommunities.  */
 void ecommunity_free(struct ecommunity **ecom)
 {
+	if (!(*ecom))
+		return;
+
 	XFREE(MTYPE_ECOMMUNITY_VAL, (*ecom)->val);
 	XFREE(MTYPE_ECOMMUNITY_STR, (*ecom)->str);
 	XFREE(MTYPE_ECOMMUNITY, *ecom);
diff --git a/bgpd/bgp_lcommunity.c b/bgpd/bgp_lcommunity.c
index 8d99548fc2..642888241f 100644
--- a/bgpd/bgp_lcommunity.c
+++ b/bgpd/bgp_lcommunity.c
@@ -44,6 +44,9 @@ static struct lcommunity *lcommunity_new(void)
 /* Allocate lcommunities.  */
 void lcommunity_free(struct lcommunity **lcom)
 {
+	if (!(*lcom))
+		return;
+
 	XFREE(MTYPE_LCOMMUNITY_VAL, (*lcom)->val);
 	XFREE(MTYPE_LCOMMUNITY_STR, (*lcom)->str);
 	XFREE(MTYPE_LCOMMUNITY, *lcom);