curl_easy_reset: reset the referer string

When CURLOPT_REFERER has been used, curl_easy_reset() did not properly
clear it.

Verified with the new test 598

Bug: http://curl.haxx.se/bug/view.cgi?id=3481551
Reported by: Michael Day

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/url.c b/lib/url.c
index 466748bfc..395055f4e 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -272,6 +272,12 @@ void Curl_freeset(struct SessionHandle * data)
   enum dupstring i;
   for(i=(enum dupstring)0; i < STRING_LAST; i++)
     Curl_safefree(data->set.str[i]);
+
+  if(data->change.referer_alloc) {
+    Curl_safefree(data->change.referer);
+    data->change.referer_alloc = FALSE;
+  }
+  data->change.referer = NULL;
 }
 
 static CURLcode setstropt(char **charp, char * s)