conserver: free correct addrinfo to prevent crash.

When looping through addrinfo lists in AddrsMatch, keep a copy of the
original addrinfo pointers to free instead of ending up at the terminating
NULLs and trying to free those.

OpenWRT uses musl in which freeaddrinfo(NULL) is not safe (which is
fine, it's not required by the spec) so this fixes a segfault.

Signed-off-by: Darren Tucker <dtucker@dtucker.net>

net/conserver/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=conserver
 PKG_VERSION:=8.2.6
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://codeload.github.com/conserver/conserver/tar.gz/v$(PKG_VERSION)?

net/conserver/patches/002-addrsmatch-freeaddrinfo.patch

@@ -0,0 +1,36 @@
+--- a/conserver/consent.c
++++ b/conserver/consent.c
+@@ -1269,7 +1269,7 @@ AddrsMatch(char *addr1, char *addr2)
+ {
+ #if USE_IPV6
+     int error, ret = 0;
+-    struct addrinfo *ai1, *ai2, hints;
++    struct addrinfo *ai1, *ai2, *rp1, *rp2, hints;
+ #else
+     /* so, since we might use inet_addr, we're going to use
+      * (in_addr_t)(-1) as a sign of an invalid ip address.
+@@ -1307,17 +1307,19 @@ AddrsMatch(char *addr1, char *addr2)
+ 	goto done;
+     }
+ 
+-    for (; ai1 != NULL; ai1 = ai1->ai_next) {
+-	for (; ai2 != NULL; ai2 = ai2->ai_next) {
+-	    if (ai1->ai_addr->sa_family != ai2->ai_addr->sa_family)
++    rp1 = ai1;
++    rp2 = ai2;
++    for (; rp1 != NULL; rp1 = rp1->ai_next) {
++	for (; rp2 != NULL; rp2 = rp2->ai_next) {
++	    if (rp1->ai_addr->sa_family != rp2->ai_addr->sa_family)
+ 		continue;
+ 
+ 	    if (
+ # if HAVE_MEMCMP
+-		   memcmp(&ai1->ai_addr, &ai2->ai_addr,
++		   memcmp(&rp1->ai_addr, &rp2->ai_addr,
+ 			  sizeof(struct sockaddr_storage))
+ # else
+-		   bcmp(&ai1->ai_addr, &ai2->ai_addr,
++		   bcmp(&rp1->ai_addr, &rp2->ai_addr,
+ 			sizeof(struct sockaddr_storage))
+ # endif
+ 		   == 0) {