https: fix memory leak with https.request()

If calling `https.request()` with `options.headers.host` defined
and `options.servername` undefined, `https.Agent.createSocket` mutates
connection `options` after `https.Agent.addRequest` has created empty
socket pool array with mismatching connection name. This results in two
socket pool arrays being created and only the last one gets eventually
deleted by `removeSocket` - causing a memory leak.

This commit fixes the leak by making sure that `addRequest` does the
same modifications to `options` object as the `createSocket`.

`createSocket` is intentionally left unmodified to prevent userland
regressions.

Test case included.

PR-URL: https://github.com/nodejs/node/pull/8647
Fixes: https://github.com/nodejs/node/issues/6687
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jackson Tian <shvyo1987@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/lib/_http_agent.js b/lib/_http_agent.js
index bac10c4dab..6ea801c3ed 100644
--- a/lib/_http_agent.js
+++ b/lib/_http_agent.js
@@ -123,6 +123,14 @@ Agent.prototype.addRequest = function(req, options) {
   options = util._extend({}, options);
   options = util._extend(options, this.options);
 
+  if (!options.servername) {
+    options.servername = options.host;
+    const hostHeader = req.getHeader('host');
+    if (hostHeader) {
+      options.servername = hostHeader.replace(/:.*$/, '');
+    }
+  }
+
   var name = this.getName(options);
   if (!this.sockets[name]) {
     this.sockets[name] = [];