From patchwork Tue Dec 18 17:52:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 10736069 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B22126C2 for ; Tue, 18 Dec 2018 17:52:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9D0DA2AC4F for ; Tue, 18 Dec 2018 17:52:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8FE7C2AC5B; Tue, 18 Dec 2018 17:52:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D14AF2AC03 for ; Tue, 18 Dec 2018 17:52:27 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 9AA73267946; Tue, 18 Dec 2018 18:52:25 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 8FF3A2679EF; Tue, 18 Dec 2018 18:52:22 +0100 (CET) Received: from gateway22.websitewelcome.com (gateway22.websitewelcome.com [192.185.47.109]) by alsa0.perex.cz (Postfix) with ESMTP id 5D0CB26782E for ; Tue, 18 Dec 2018 18:52:19 +0100 (CET) Received: from cm14.websitewelcome.com (cm14.websitewelcome.com [100.42.49.7]) by gateway22.websitewelcome.com (Postfix) with ESMTP id B62BD11DAB for ; Tue, 18 Dec 2018 11:52:18 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id ZJXWgBkPd2qH7ZJXWgujO0; Tue, 18 Dec 2018 11:52:18 -0600 X-Authority-Reason: nr=8 Received: from [189.250.106.44] (port=32796 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gZJXV-002P9c-Dr; Tue, 18 Dec 2018 11:52:17 -0600 Date: Tue, 18 Dec 2018 11:52:16 -0600 From: "Gustavo A. R. Silva" To: Jaroslav Kysela , Takashi Iwai Message-ID: <20181218175216.GA16070@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - alsa-project.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.106.44 X-Source-L: No X-Exim-ID: 1gZJXV-002P9c-Dr X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.106.44]:32796 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 12 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [alsa-devel] [PATCH] ALSA: emu10k1: Fix potential Spectre v1 vulnerabilities X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP ipcm->substream is indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: sound/pci/emu10k1/emufx.c:1031 snd_emu10k1_ipcm_poke() warn: potential spectre issue 'emu->fx8010.pcm' [r] (local cap) sound/pci/emu10k1/emufx.c:1075 snd_emu10k1_ipcm_peek() warn: potential spectre issue 'emu->fx8010.pcm' [r] (local cap) Fix this by sanitizing ipcm->substream before using it to index emu->fx8010.pcm Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva --- sound/pci/emu10k1/emufx.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sound/pci/emu10k1/emufx.c b/sound/pci/emu10k1/emufx.c index 6ebe817801ea..1f25e6d029d8 100644 --- a/sound/pci/emu10k1/emufx.c +++ b/sound/pci/emu10k1/emufx.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include @@ -1026,6 +1027,8 @@ static int snd_emu10k1_ipcm_poke(struct snd_emu10k1 *emu, if (ipcm->substream >= EMU10K1_FX8010_PCM_COUNT) return -EINVAL; + ipcm->substream = array_index_nospec(ipcm->substream, + EMU10K1_FX8010_PCM_COUNT); if (ipcm->channels > 32) return -EINVAL; pcm = &emu->fx8010.pcm[ipcm->substream]; @@ -1072,6 +1075,8 @@ static int snd_emu10k1_ipcm_peek(struct snd_emu10k1 *emu, if (ipcm->substream >= EMU10K1_FX8010_PCM_COUNT) return -EINVAL; + ipcm->substream = array_index_nospec(ipcm->substream, + EMU10K1_FX8010_PCM_COUNT); pcm = &emu->fx8010.pcm[ipcm->substream]; mutex_lock(&emu->fx8010.lock); spin_lock_irq(&emu->reg_lock);