From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754899AbdJINTQ (ORCPT ); Mon, 9 Oct 2017 09:19:16 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43462 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754894AbdJINTL (ORCPT ); Mon, 9 Oct 2017 09:19:11 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Trond Myklebust" , "Anna Schumaker" , "Anna Schumaker" , "Jeff Layton" , "Jason A. Donenfeld" , linux-nfs@vger.kernel.org, "J. Bruce Fields" Date: Mon, 09 Oct 2017 13:44:24 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 113/192] sunrpc: use constant time memory comparison for mac In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Jason A. Donenfeld" commit 15a8b93fd5690de017ce665382ea45e5d61811a4 upstream. Otherwise, we enable a MAC forgery via timing attack. Signed-off-by: Jason A. Donenfeld Cc: "J. Bruce Fields" Cc: Jeff Layton Cc: Trond Myklebust Cc: Anna Schumaker Cc: linux-nfs@vger.kernel.org Signed-off-by: Anna Schumaker [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- net/sunrpc/auth_gss/gss_krb5_crypto.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sunrpc/auth_gss/gss_krb5_crypto.c +++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c @@ -34,6 +34,7 @@ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ +#include #include #include #include @@ -838,7 +839,7 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kc if (ret) goto out_err; - if (memcmp(pkt_hmac, our_hmac, kctx->gk5e->cksumlength) != 0) { + if (crypto_memneq(pkt_hmac, our_hmac, kctx->gk5e->cksumlength) != 0) { ret = GSS_S_BAD_SIG; goto out_err; }