Additional check to handle BAD SSL_write retry

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from openssl#3124)

ssl/record/rec_layer_s3.c

@@ -356,7 +356,8 @@ int ssl3_write_bytes(SSL *s, int type, const void *buf_, size_t len,
      * promptly send beyond the end of the users buffer ... so we trap and
      * report the error in a way the user will notice
      */
-    if (len < s->rlayer.wnum) {
+    if ((len < s->rlayer.wnum) 
+        || ((wb->left != 0) && (len < (s->rlayer.wnum + s->rlayer.wpend_tot)))) {
         SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH);
         return -1;
     }