http: reset the header buffer when sending the request
A reused transfer handle could otherwise reuse the previous leftover
buffer and havoc would ensue.
Reported-by: sergio-nsk on github
Fixes #7018
Closes #7021
diff --git a/lib/http.c b/lib/http.c
index b42d37e..eece055 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -3120,6 +3120,10 @@
/* initialize a dynamic send-buffer */
Curl_dyn_init(&req, DYN_HTTP_REQUEST);
+ /* make sure the header buffer is reset - if there are leftovers from a
+ previous transfer */
+ Curl_dyn_reset(&data->state.headerb);
+
/* add the main request stuff */
/* GET/HEAD/POST/PUT */
result = Curl_dyn_addf(&req, "%s ", request);
