Curl_pgrsTime - return new time to avoid timeout integer overflowbagder/timeout-overflow

Setting a timeout to INT_MAX could cause an immediate error to get
returned as timeout because of an overflow when different values of
'now' were used.

This is primarily fixed by having Curl_pgrsTime() return the "now" when
TIMER_STARTSINGLE is set so that the parent function will continue using
that time.

Reported-by: Ionuț-Francisc Oancea
Fixes #5583

1 files changed, 7 insertions, 2 deletions

diff --git a/lib/progress.c b/lib/progress.c
index 895138448..eced74c9f 100644
--- a/lib/progress.c
+++ b/lib/progress.c
@@ -164,9 +164,13 @@ void Curl_pgrsResetTransferSizes(struct Curl_easy *data)
 }
 
 /*
+ *
+ * Curl_pgrsTime(). Store the current time at the given label. This fetches a
+ * fresh "now" and returns it.
+ *
  * @unittest: 1399
  */
-void Curl_pgrsTime(struct Curl_easy *data, timerid timer)
+struct curltime Curl_pgrsTime(struct Curl_easy *data, timerid timer)
 {
   struct curltime now = Curl_now();
   timediff_t *delta = NULL;
@@ -209,7 +213,7 @@ void Curl_pgrsTime(struct Curl_easy *data, timerid timer)
      * changing the t_starttransfer time.
      */
     if(data->progress.is_t_startransfer_set) {
-      return;
+      return now;
     }
     else {
       data->progress.is_t_startransfer_set = true;
@@ -228,6 +232,7 @@ void Curl_pgrsTime(struct Curl_easy *data, timerid timer)
       us = 1; /* make sure at least one microsecond passed */
     *delta += us;
   }
+  return now;
 }
 
 void Curl_pgrsStartNow(struct Curl_easy *data)