apps/s_client.c: add missing null check

apps/s_server.c: remove unnecessary null check
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4558)

apps/s_client.c

@@ -1866,6 +1866,9 @@ int s_client_main(int argc, char **argv)
         goto end;
 
     con = SSL_new(ctx);
+    if (con == NULL)
+        goto end;
+
     if (sess_in != NULL) {
         SSL_SESSION *sess;
         BIO *stmp = BIO_new_file(sess_in, "r");

apps/s_server.c

@@ -2202,22 +2202,25 @@ static int sv_body(int s, int stype, int prot, unsigned char *context)
             BIO_printf(bio_err, "Turned on non blocking io\n");
     }
 
-    if (con == NULL) {
     con = SSL_new(ctx);
+    if (con == NULL) {
+        ret = -1;
+        goto err;
+    }
 
     if (s_tlsextdebug) {
         SSL_set_tlsext_debug_callback(con, tlsext_cb);
         SSL_set_tlsext_debug_arg(con, bio_s_out);
     }
 
-        if (context
-            && !SSL_set_session_id_context(con,
-                                           context, strlen((char *)context))) {
+    if (context != NULL
+        && !SSL_set_session_id_context(con, context,
+                                       strlen((char *)context))) {
         BIO_printf(bio_err, "Error setting session id context\n");
         ret = -1;
         goto err;
     }
-    }
+
     if (!SSL_clear(con)) {
         BIO_printf(bio_err, "Error clearing SSL connection\n");
         ret = -1;