Merge branch 'master' of https://github.com/curl/curl

1 files changed, 22 insertions, 15 deletions

diff --git a/lib/smtp.c b/lib/smtp.c
index 76958603b..7fc76c956 100644
--- a/lib/smtp.c
+++ b/lib/smtp.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -232,23 +232,30 @@ static bool smtp_endofresp(struct connectdata *conn, char *line, size_t len,
  */
 static void smtp_get_message(char *buffer, char **outptr)
 {
-  size_t len = 0;
+  size_t len = strlen(buffer);
   char *message = NULL;
 
-  /* Find the start of the message */
-  for(message = buffer + 4; *message == ' ' || *message == '\t'; message++)
-    ;
-
-  /* Find the end of the message */
-  for(len = strlen(message); len--;)
-    if(message[len] != '\r' && message[len] != '\n' && message[len] != ' ' &&
-       message[len] != '\t')
-      break;
-
-  /* Terminate the message */
-  if(++len) {
-    message[len] = '\0';
+  if(len > 4) {
+    /* Find the start of the message */
+    len -= 4;
+    for(message = buffer + 4; *message == ' ' || *message == '\t';
+        message++, len--)
+      ;
+
+    /* Find the end of the message */
+    for(; len--;)
+      if(message[len] != '\r' && message[len] != '\n' && message[len] != ' ' &&
+         message[len] != '\t')
+        break;
+
+    /* Terminate the message */
+    if(++len) {
+      message[len] = '\0';
+    }
   }
+  else
+    /* junk input => zero length output */
+    message = &buffer[len];
 
   *outptr = message;
 }