libglusterfs: fix dict leak

Problem:
gf_rev_dns_lookup_cached() allocated struct dnscache->dict if it was null
but the freeing was left to the caller.

Fix:
Moved dict allocation and freeing into corresponding init and fini
routines so that its easier for the caller to avoid such leaks.

Updates: #1000
Change-Id: I90d6a6f85ca2dd4fe0ab461177aaa9ac9c1fbcf9
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
(cherry picked from commit 079f7a7d8a2bd85070c1da4dde2452ca82a1cdbb)

1 files changed, 22 insertions, 8 deletions

diff --git a/libglusterfs/src/common-utils.c b/libglusterfs/src/common-utils.c
index 585952d7641..20c2310cc38 100644
--- a/libglusterfs/src/common-utils.c
+++ b/libglusterfs/src/common-utils.c
@@ -564,8 +564,14 @@ struct dnscache *
 gf_dnscache_init(time_t ttl)
 {
     struct dnscache *cache = GF_MALLOC(sizeof(*cache), gf_common_mt_dnscache);
-    if (cache) {
-        cache->cache_dict = NULL;
+    if (!cache)
+        return NULL;
+
+    cache->cache_dict = dict_new();
+    if (!cache->cache_dict) {
+        GF_FREE(cache);
+        cache = NULL;
+    } else {
         cache->ttl = ttl;
     }
 
@@ -573,6 +579,20 @@ gf_dnscache_init(time_t ttl)
 }
 
 /**
+ * gf_dnscache_deinit -- cleanup resources used by struct dnscache
+ */
+void
+gf_dnscache_deinit(struct dnscache *cache)
+{
+    if (!cache) {
+        gf_msg_plain(GF_LOG_WARNING, "dnscache is NULL");
+        return;
+    }
+    dict_unref(cache->cache_dict);
+    GF_FREE(cache);
+}
+
+/**
  * gf_dnscache_entry_init -- Initialize a dnscache entry
  *
  * @return: SUCCESS: Pointer to an allocated dnscache entry struct
@@ -620,12 +640,6 @@ gf_rev_dns_lookup_cached(const char *ip, struct dnscache *dnscache)
     if (!dnscache)
         goto out;
 
-    if (!dnscache->cache_dict) {
-        dnscache->cache_dict = dict_new();
-        if (!dnscache->cache_dict) {
-            goto out;
-        }
-    }
     cache = dnscache->cache_dict;
 
     /* Quick cache lookup to see if we already hold it */