Merge pull request #5531 from embhorn/zd14665

Check return from call to wc_Time

wolfcrypt/src/asn.c

@@ -13727,6 +13727,12 @@ int wc_ValidateDate(const byte* date, byte format, int dateType)
     (void)tmpTime;
 
     ltime = wc_Time(0);
+    if (ltime < 0){
+        /* A negative response here could be due to a 32-bit time_t
+         * where the year is 2038 or later. */
+        WOLFSSL_MSG("wc_Time failed to return a valid value");
+        return 0;
+    }
 
 #ifdef WOLFSSL_BEFORE_DATE_CLOCK_SKEW
     if (dateType == BEFORE) {