From 3fc678a8df4d6c057ef9f2c602b86ed106651e68 Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@tinc-vpn.org>
Date: Tue, 7 Mar 2017 19:19:19 +0100
Subject: [PATCH] Use free_known_addresses() to free memory allocated by
 get_known_addresses().

We know what struct addrinfo looks like, but the standard says nothing
about how it is allocated. So we cannot trust freeaddrinfo() to work
correctly on the struct addrinfo list we allocated ourselves in
get_known_addresses(). To make a distinction by allocations from the
latter and from str2addrinfo(), we keep two pointers (*ai and *kai) in
struct outgoing, and use the freeing function that is appropriate for
each.
---
 src/net.h        |  3 ++-
 src/net_socket.c | 21 ++++++++++++++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/src/net.h b/src/net.h
index 7080869..69ca488 100644
--- a/src/net.h
+++ b/src/net.h
@@ -126,8 +126,9 @@ typedef struct outgoing_t {
 	int timeout;
 	splay_tree_t *config_tree;
 	struct config_t *cfg;
-	struct addrinfo *ai;
+	struct addrinfo *ai;  // addresses from config files
 	struct addrinfo *aip;
+	struct addrinfo *kai; // addresses known via other online nodes (use free_known_addresses())
 	timeout_t ev;
 } outgoing_t;
 
diff --git a/src/net_socket.c b/src/net_socket.c
index 36ea5fe..a1934e9 100644
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -441,13 +441,20 @@ static void handle_meta_io(void *data, int flags) {
 		handle_meta_connection_data(c);
 }
 
+static void free_known_addresses(struct addrinfo *ai) {
+	for(struct addrinfo *aip = ai, *next; aip; aip = next) {
+		next = aip->ai_next;
+		free(aip);
+	}
+}
+
 bool do_outgoing_connection(outgoing_t *outgoing) {
 	char *address, *port, *space;
 	struct addrinfo *proxyai = NULL;
 	int result;
 
 begin:
-	if(!outgoing->ai) {
+	if(!outgoing->ai && !outgoing->kai) {
 		if(!outgoing->cfg) {
 			logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not set up a meta connection to %s", outgoing->name);
 			retry_outgoing(outgoing);
@@ -477,6 +484,11 @@ begin:
 		if(outgoing->ai)
 			freeaddrinfo(outgoing->ai);
 		outgoing->ai = NULL;
+
+		if(outgoing->kai)
+			free_known_addresses(outgoing->kai);
+		outgoing->kai = NULL;
+
 		goto begin;
 	}
 
@@ -621,8 +633,8 @@ void setup_outgoing_connection(outgoing_t *outgoing) {
 
 	if(!outgoing->cfg) {
 		if(n)
-			outgoing->aip = outgoing->ai = get_known_addresses(n);
-		if(!outgoing->ai) {
+			outgoing->aip = outgoing->kai = get_known_addresses(n);
+		if(!outgoing->kai) {
 			logger(DEBUG_ALWAYS, LOG_DEBUG, "No address known for %s", outgoing->name);
 			goto remove;
 		}
@@ -777,6 +789,9 @@ static void free_outgoing(outgoing_t *outgoing) {
 	if(outgoing->ai)
 		freeaddrinfo(outgoing->ai);
 
+	if(outgoing->kai)
+		free_known_addresses(outgoing->kai);
+
 	if(outgoing->config_tree)
 		exit_configuration(&outgoing->config_tree);
 
-- 
2.25.1