- Patrick Scott found a rather large memory leak when using the multi

interface and setting CURLMOPT_MAXCONNECTS to something less than the number
  of handles you add to the multi handle. All the connections that didn't fit
  in the cache would not be properly disconnected nor freed!

CHANGES

@@ -7,6 +7,11 @@
                                   Changelog
 
 Daniel Stenberg (2 Feb 2009)
+- Patrick Scott found a rather large memory leak when using the multi
+  interface and setting CURLMOPT_MAXCONNECTS to something less than the number
+  of handles you add to the multi handle. All the connections that didn't fit
+  in the cache would not be properly disconnected nor freed!
+
 - Craig A West brought us: libcurl now defaults to do CONNECT with HTTP
   version 1.1 instead of 1.0 like before. This change also introduces the new
   proxy type for libcurl called 'CURLPROXY_HTTP_1_0' that then allows apps to

RELEASE-NOTES

@@ -25,6 +25,7 @@ This release includes the following bugfixes:
  o FTP ;type=i URLs now work with CURLOPT_PROXY_TRANSFER_MODE in Turkish locale
  o realms with quoted quotation marks in HTTP Digest headers
  o VC9 makefiles are now really included
+ o multi interface memory leak with CURLMOPT_MAXCONNECTS set
 
 This release includes the following known bugs:
 
@@ -34,6 +35,7 @@ This release would not have looked like this without help, code, reports and
 advice from friends like these:
 
  Lisa Xu, Daniel Fandrich, Craig A West, Alexey Borzov, Sharad Gupta,
- Peter Sylvester, Chad Monroe, Markus Moeller, Yang Tse, Scott Cantor
+ Peter Sylvester, Chad Monroe, Markus Moeller, Yang Tse, Scott Cantor,
+ Patrick Scott
 
         Thanks! (and sorry if I forgot to mention someone)

lib/url.c

@@ -4804,8 +4804,12 @@ CURLcode Curl_done(struct connectdata **connp,
      state it is for re-using, so we're forced to close it. In a perfect world
      we can add code that keep track of if we really must close it here or not,
      but currently we have no such detail knowledge.
+
+     connectindex == -1 here means that the connection has no spot in the
+     connection cache and thus we must disconnect it here.
   */
-  if(data->set.reuse_forbid || conn->bits.close || premature) {
+  if(data->set.reuse_forbid || conn->bits.close || premature ||
+     (-1 == conn->connectindex)) {
     CURLcode res2 = Curl_disconnect(conn); /* close the connection */
 
     /* If we had an error already, make sure we return that one. But