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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 63326C7112B for ; Sun, 14 Oct 2018 15:30:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35F2820835 for ; Sun, 14 Oct 2018 15:30:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 35F2820835 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727233AbeJNXLp (ORCPT ); Sun, 14 Oct 2018 19:11:45 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35701 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727072AbeJNXLo (ORCPT ); Sun, 14 Oct 2018 19:11:44 -0400 Received: from [2a02:8011:400e:2:cbab:f00:c93f:614] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1gBiLX-0004cF-L4; Sun, 14 Oct 2018 16:30:23 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gBiLV-0000Ru-BN; Sun, 14 Oct 2018 16:30:21 +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, "Dan Carpenter" , "Takashi Iwai" Date: Sun, 14 Oct 2018 16:25:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 215/366] ALSA: hda: Hardening for potential Spectre v1 In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:cbab:f00:c93f:614 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 3.16.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit 69fa6f19b95597618ab30438a27b67ad93daa7c7 upstream. As recently Smatch suggested, one place in HD-audio hwdep ioctl codes may expand the array directly from the user-space value with speculation: sound/pci/hda/hda_local.h:467 get_wcaps() warn: potential spectre issue 'codec->wcaps' As get_wcaps() itself is a fairly frequently called inline function, and there is only one single call with a user-space value, we replace only the latter one to open-code locally with array_index_nospec() hardening in this patch. BugLink: https://marc.info/?l=linux-kernel&m=152411496503418&w=2 Reported-by: Dan Carpenter Signed-off-by: Takashi Iwai [bwh: Backported to 3.16: s/core\.//g] Signed-off-by: Ben Hutchings --- sound/pci/hda/hda_hwdep.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/sound/pci/hda/hda_hwdep.c +++ b/sound/pci/hda/hda_hwdep.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include "hda_codec.h" #include "hda_local.h" @@ -51,7 +52,16 @@ static int get_wcap_ioctl(struct hda_cod if (get_user(verb, &arg->verb)) return -EFAULT; - res = get_wcaps(codec, verb >> 24); + /* open-code get_wcaps(verb>>24) with nospec */ + verb >>= 24; + if (verb < codec->start_nid || + verb >= codec->start_nid + codec->num_nodes) { + res = 0; + } else { + verb -= codec->start_nid; + verb = array_index_nospec(verb, codec->num_nodes); + res = codec->wcaps[verb]; + } if (put_user(res, &arg->res)) return -EFAULT; return 0;