From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2D684C48BDE for ; Sun, 7 Jul 2019 19:45:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03BEC20651 for ; Sun, 7 Jul 2019 19:45:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728562AbfGGTpI (ORCPT ); Sun, 7 Jul 2019 15:45:08 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57166 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727531AbfGGTiG (ORCPT ); Sun, 7 Jul 2019 15:38:06 -0400 Received: from 94.197.121.43.threembb.co.uk ([94.197.121.43] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hkCz4-0006gF-9w; Sun, 07 Jul 2019 20:38:02 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hkCz3-0005Zp-1P; Sun, 07 Jul 2019 20:38:01 +0100 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, Denis Kirjanov , "Eric Biggers" , "Ard Biesheuvel" , "Herbert Xu" Date: Sun, 07 Jul 2019 17:54:17 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 044/129] crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling In-Reply-To: X-SA-Exim-Connect-IP: 94.197.121.43 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ard Biesheuvel commit eaf46edf6ea89675bd36245369c8de5063a0272c upstream. The NEON MAC calculation routine fails to handle the case correctly where there is some data in the buffer, and the input fills it up exactly. In this case, we enter the loop at the end with w8 == 0, while a negative value is assumed, and so the loop carries on until the increment of the 32-bit counter wraps around, which is quite obviously wrong. So omit the loop altogether in this case, and exit right away. Reported-by: Eric Biggers Fixes: a3fd82105b9d1 ("arm64/crypto: AES in CCM mode using ARMv8 Crypto ...") Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Ben Hutchings --- arch/arm64/crypto/aes-ce-ccm-core.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/arm64/crypto/aes-ce-ccm-core.S +++ b/arch/arm64/crypto/aes-ce-ccm-core.S @@ -74,12 +74,13 @@ ENTRY(ce_aes_ccm_auth_data) beq 10f ext v0.16b, v0.16b, v0.16b, #1 /* rotate out the mac bytes */ b 7b -8: mov w7, w8 +8: cbz w8, 91f + mov w7, w8 add w8, w8, #16 9: ext v1.16b, v1.16b, v1.16b, #1 adds w7, w7, #1 bne 9b - eor v0.16b, v0.16b, v1.16b +91: eor v0.16b, v0.16b, v1.16b st1 {v0.16b}, [x0] 10: str w8, [x3] ret