Fixed issue where struct env_set methods that

change the value of an existing name=value pair
would delay the freeing of the memory held by
the previous name=value pair until the underlying
client instance object is closed.

This could cause a server that handles long-term
client connections, resulting in many periodic calls
to verify_callback, to needlessly grow the env_set
memory allocation until the underlying client instance
object is closed.


git-svn-id: http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn@1493 e7ae566f-a301-0410-adde-c780ea21d3b5

init.c

@@ -2272,10 +2272,22 @@ do_close_ifconfig_pool_persist (struct context *c)
 static void
 do_inherit_env (struct context *c, const struct env_set *src)
 {
-  c->c2.es = env_set_create (&c->c2.gc);
+  c->c2.es = env_set_create (NULL);
+  c->c2.es_owned = true;
   env_set_inherit (c->c2.es, src);
 }
 
+static void
+do_env_set_destroy (struct context *c)
+{
+  if (c->c2.es && c->c2.es_owned)
+    {
+      env_set_destroy (c->c2.es);
+      c->c2.es = NULL;
+      c->c2.es_owned = false;
+    }
+}
+
 /*
  * Fast I/O setup.  Fast I/O is an optimization which only works
  * if all of the following are true:
@@ -2798,6 +2810,9 @@ close_instance (struct context *c)
 	/* close --ifconfig-pool-persist obj */
 	do_close_ifconfig_pool_persist (c);
 
+	/* free up environmental variable store */
+	do_env_set_destroy (c);
+
 	/* garbage collect */
 	gc_free (&c->c2.gc);
       }
@@ -2922,6 +2937,7 @@ inherit_context_top (struct context *dest,
   dest->c2.event_set_owned = false;
   dest->c2.link_socket_owned = false;
   dest->c2.buffers_owned = false;
+  dest->c2.es_owned = false;
 
   dest->c2.event_set = NULL;
   if (src->options.proto == PROTO_UDPv4)

misc.c

@@ -690,13 +690,13 @@ add_env_item (char *str, const bool do_alloc, struct env_item **list, struct gc_
 static bool
 env_set_del_nolock (struct env_set *es, const char *str)
 {
-  return remove_env_item (str, false, &es->list);
+  return remove_env_item (str, es->gc == NULL, &es->list);
 }
 
 static void
 env_set_add_nolock (struct env_set *es, const char *str)
 {
-  remove_env_item (str, false, &es->list);  
+  remove_env_item (str, es->gc == NULL, &es->list);  
   add_env_item ((char *)str, true, &es->list, es->gc);
 }
 
@@ -704,7 +704,6 @@ struct env_set *
 env_set_create (struct gc_arena *gc)
 {
   struct env_set *es;
-  ASSERT (gc);
   mutex_lock_static (L_ENV_SET);
   ALLOC_OBJ_CLEAR_GC (es, struct env_set, gc);
   es->list = NULL;
@@ -713,6 +712,25 @@ env_set_create (struct gc_arena *gc)
   return es;
 }
 
+void
+env_set_destroy (struct env_set *es)
+{
+  mutex_lock_static (L_ENV_SET);
+  if (es && es->gc == NULL)
+    {
+      struct env_item *e = es->list;
+      while (e)
+	{
+	  struct env_item *next = e->next;
+	  free (e->string);
+	  free (e);
+	  e = next;
+	}
+      free (es);
+    }
+  mutex_unlock_static (L_ENV_SET);
+}
+
 bool
 env_set_del (struct env_set *es, const char *str)
 {

misc.h

@@ -168,6 +168,7 @@ void setenv_del (struct env_set *es, const char *name);
 /* struct env_set functions */
 
 struct env_set *env_set_create (struct gc_arena *gc);
+void env_set_destroy (struct env_set *es);
 bool env_set_del (struct env_set *es, const char *str);
 void env_set_add (struct env_set *es, const char *str);
 

openvpn.h

@@ -403,6 +403,7 @@ struct context_2
 
   /* environmental variables to pass to scripts */
   struct env_set *es;
+  bool es_owned;
 
   /* don't wait for TUN/TAP/UDP to be ready to accept write */
   bool fast_io;