curl: cap the maximum allowed values for retry time arguments

... to avoid integer overflows later when multiplying with 1000 to
convert seconds to milliseconds.

Added test 1269 to verify.

Reported-by: Jason Lee
Closes #4166

src/tool_getparam.c

@@ -911,12 +911,12 @@ ParameterError getparameter(const char *flag, /* f or -long-flag */
         config->retry_connrefused = toggle;
         break;
       case 'h': /* --retry-delay */
-        err = str2unum(&config->retry_delay, nextarg);
+        err = str2unummax(&config->retry_delay, nextarg, LONG_MAX/1000);
         if(err)
           return err;
         break;
       case 'i': /* --retry-max-time */
-        err = str2unum(&config->retry_maxtime, nextarg);
+        err = str2unummax(&config->retry_maxtime, nextarg, LONG_MAX/1000);
         if(err)
           return err;
         break;

src/tool_paramhlp.c

@@ -197,6 +197,28 @@ ParameterError str2unum(long *val, const char *str)
   return PARAM_OK;
 }
 
+/*
+ * Parse the string and write the long in the given address if it is below the
+ * maximum allowed value. Return PARAM_OK on success, otherwise a parameter
+ * error enum. ONLY ACCEPTS POSITIVE NUMBERS!
+ *
+ * Since this function gets called with the 'nextarg' pointer from within the
+ * getparameter a lot, we must check it for NULL before accessing the str
+ * data.
+ */
+
+ParameterError str2unummax(long *val, const char *str, long max)
+{
+  ParameterError result = str2unum(val, str);
+  if(result != PARAM_OK)
+    return result;
+  if(*val > max)
+    return PARAM_NUMBER_TOO_LARGE;
+
+  return PARAM_OK;
+}
+
+
 /*
  * Parse the string and write the double in the given address. Return PARAM_OK
  * on success, otherwise a parameter specific error enum.

src/tool_paramhlp.h

@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2019, 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
@@ -33,6 +33,7 @@ void cleanarg(char *str);
 
 ParameterError str2num(long *val, const char *str);
 ParameterError str2unum(long *val, const char *str);
+ParameterError str2unummax(long *val, const char *str, long max);
 ParameterError str2udouble(double *val, const char *str, long max);
 
 long proto2num(struct OperationConfig *config, long *val, const char *str);