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 2272BC7112A for ; Sun, 14 Oct 2018 15:32:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E8F5520835 for ; Sun, 14 Oct 2018 15:32:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E8F5520835 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 S1728555AbeJNXNZ (ORCPT ); Sun, 14 Oct 2018 19:13:25 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36395 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728258AbeJNXMH (ORCPT ); Sun, 14 Oct 2018 19:12:07 -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 1gBiLu-0004cZ-Aa; Sun, 14 Oct 2018 16:30:46 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gBiLV-0000SS-GG; 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 3.16 219/366] ALSA: hdspm: 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 10513142a7114d251670361ad40cba2c61403406 upstream. As recently Smatch suggested, a couple of places in HDSP MADI driver may expand the array directly from the user-space value with speculation: sound/pci/rme9652/hdspm.c:5717 snd_hdspm_channel_info() warn: potential spectre issue 'hdspm->channel_map_out' (local cap) sound/pci/rme9652/hdspm.c:5734 snd_hdspm_channel_info() warn: potential spectre issue 'hdspm->channel_map_in' (local cap) This patch puts array_index_nospec() for hardening against them. 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: adjust context] Signed-off-by: Ben Hutchings --- sound/pci/rme9652/hdspm.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) --- a/sound/pci/rme9652/hdspm.c +++ b/sound/pci/rme9652/hdspm.c @@ -137,6 +137,7 @@ #include #include #include +#include #include #include @@ -5724,40 +5725,43 @@ static int snd_hdspm_channel_info(struct struct snd_pcm_channel_info *info) { struct hdspm *hdspm = snd_pcm_substream_chip(substream); + unsigned int channel = info->channel; if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { - if (snd_BUG_ON(info->channel >= hdspm->max_channels_out)) { + if (snd_BUG_ON(channel >= hdspm->max_channels_out)) { dev_info(hdspm->card->dev, "snd_hdspm_channel_info: output channel out of range (%d)\n", - info->channel); + channel); return -EINVAL; } - if (hdspm->channel_map_out[info->channel] < 0) { + channel = array_index_nospec(channel, hdspm->max_channels_out); + if (hdspm->channel_map_out[channel] < 0) { dev_info(hdspm->card->dev, "snd_hdspm_channel_info: output channel %d mapped out\n", - info->channel); + channel); return -EINVAL; } - info->offset = hdspm->channel_map_out[info->channel] * + info->offset = hdspm->channel_map_out[channel] * HDSPM_CHANNEL_BUFFER_BYTES; } else { - if (snd_BUG_ON(info->channel >= hdspm->max_channels_in)) { + if (snd_BUG_ON(channel >= hdspm->max_channels_in)) { dev_info(hdspm->card->dev, "snd_hdspm_channel_info: input channel out of range (%d)\n", - info->channel); + channel); return -EINVAL; } - if (hdspm->channel_map_in[info->channel] < 0) { + channel = array_index_nospec(channel, hdspm->max_channels_in); + if (hdspm->channel_map_in[channel] < 0) { dev_info(hdspm->card->dev, "snd_hdspm_channel_info: input channel %d mapped out\n", - info->channel); + channel); return -EINVAL; } - info->offset = hdspm->channel_map_in[info->channel] * + info->offset = hdspm->channel_map_in[channel] * HDSPM_CHANNEL_BUFFER_BYTES; }