From: Ondrej Zajicek <santiago@crfreenet.org>
Date: Sun, 19 Feb 2023 02:59:10 +0000 (+0100)
Subject: Conf: Fix too early free of old configuration
X-Git-Tag: v3.0-alpha1~10^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=eefb29679957fed3724e6d5db2ddf112e28f646f;p=thirdparty%2Fbird.git

Conf: Fix too early free of old configuration

The change 371eb49043d225d2bab8149187b813a14b4b86d2 introduced early free
of old_config. Unfortunately, it did not properly check whether it is not
still in use (blocked by obstacle during reconfiguration). Fix that.

It also means that we still could have a short peak when three configs
are in use (when a new reconfig is requeste while the previous one is
still active).
---

diff --git a/conf/conf.c b/conf/conf.c
index 4e31de293..7ef729b33 100644
--- a/conf/conf.c
+++ b/conf/conf.c
@@ -197,8 +197,12 @@ cleanup:
 void
 config_free(struct config *c)
 {
-  if (c)
-    rfree(c->pool);
+  if (!c)
+    return;
+
+  ASSERT(!c->obstacle_count);
+
+  rfree(c->pool);
 }
 
 /**
@@ -207,10 +211,14 @@ config_free(struct config *c)
  * This function frees the old configuration (%old_config) that is saved for the
  * purpose of undo. It is useful before parsing a new config when reconfig is
  * requested, to avoid keeping three (perhaps memory-heavy) configs together.
+ * Configuration is not freed when it is still active during reconfiguration.
  */
 void
 config_free_old(void)
 {
+  if (!old_config || old_config->obstacle_count)
+    return;
+
   tm_stop(config_timer);
   undo_available = 0;