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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 0E0DEC43381 for ; Mon, 1 Apr 2019 18:02:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D408720883 for ; Mon, 1 Apr 2019 18:02:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554141724; bh=rwuz49IjaP+mQZNQyy8xdDAXeEaI4CkIizylPBb760w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UWLKnyoxZbrQseWzarD2i2WNNenZXfSdylh2I/wcuwYgnPUNREkkZd1f1976xy09n bLLB79MHIt5NVAEdzrzI5GF6Q01+JwkQLADrlcrp25/CjZoGMKBPGUlTYjPVaV4pj/ JuNSRhnCt7Wu3vCNosmTW3OGKE7A+8yKfZKdPsMA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730869AbfDARPN (ORCPT ); Mon, 1 Apr 2019 13:15:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:39198 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730864AbfDARPN (ORCPT ); Mon, 1 Apr 2019 13:15:13 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0A93920856; Mon, 1 Apr 2019 17:15:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554138912; bh=rwuz49IjaP+mQZNQyy8xdDAXeEaI4CkIizylPBb760w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WgMitgKABq/neB2d9nXAv3zUP3zl2IZKZyJdUMnHy5YPaRLS9lAy/t1ESVjI87XRU +yBpqeBDobLUxaizNR8Yn/8yBvzdLwADcqRo+3CC1kat2Qe8L/DtL6uIoYB4h2SxkQ 3EoQWXGXKWKY3rSNUmyW7eoopTQmuCnHoOotTQwI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gustavo A. R. Silva" , Takashi Iwai Subject: [PATCH 4.19 057/134] ALSA: rawmidi: Fix potential Spectre v1 vulnerability Date: Mon, 1 Apr 2019 19:01:33 +0200 Message-Id: <20190401170049.967599412@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170044.243719205@linuxfoundation.org> References: <20190401170044.243719205@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit 2b1d9c8f87235f593826b9cf46ec10247741fff9 upstream. info->stream 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/core/rawmidi.c:604 __snd_rawmidi_info_select() warn: potential spectre issue 'rmidi->streams' [r] (local cap) Fix this by sanitizing info->stream before using it to index rmidi->streams. 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://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/ Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/rawmidi.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/core/rawmidi.c +++ b/sound/core/rawmidi.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -601,6 +602,7 @@ static int __snd_rawmidi_info_select(str return -ENXIO; if (info->stream < 0 || info->stream > 1) return -EINVAL; + info->stream = array_index_nospec(info->stream, 2); pstr = &rmidi->streams[info->stream]; if (pstr->substream_count == 0) return -ENOENT;