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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 4DFC2C10F0E for ; Mon, 15 Apr 2019 19:35:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 19DCF20651 for ; Mon, 15 Apr 2019 19:35:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728583AbfDOTfU (ORCPT ); Mon, 15 Apr 2019 15:35:20 -0400 Received: from gateway32.websitewelcome.com ([192.185.145.171]:13556 "EHLO gateway32.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728061AbfDOTfU (ORCPT ); Mon, 15 Apr 2019 15:35:20 -0400 Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway32.websitewelcome.com (Postfix) with ESMTP id B48917463D for ; Mon, 15 Apr 2019 14:35:18 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id G7Nuh9e4LiQerG7NuhsIl9; Mon, 15 Apr 2019 14:35:18 -0500 X-Authority-Reason: nr=8 Received: from [189.250.55.242] (port=52672 helo=[192.168.43.131]) by gator4166.hostgator.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.91) (envelope-from ) id 1hG7Nu-000A88-5G; Mon, 15 Apr 2019 14:35:18 -0500 Subject: Re: [PATCH] ALSA: isa/wavefront: Fix potential Spectre v1 vulnerabilities To: Jaroslav Kysela , Takashi Iwai Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org References: <20190326183202.GA17285@embeddedor> From: "Gustavo A. R. Silva" Openpgp: preference=signencrypt Autocrypt: addr=gustavo@embeddedor.com; keydata= mQINBFssHAwBEADIy3ZoPq3z5UpsUknd2v+IQud4TMJnJLTeXgTf4biSDSrXn73JQgsISBwG 2Pm4wnOyEgYUyJd5tRWcIbsURAgei918mck3tugT7AQiTUN3/5aAzqe/4ApDUC+uWNkpNnSV tjOx1hBpla0ifywy4bvFobwSh5/I3qohxDx+c1obd8Bp/B/iaOtnq0inli/8rlvKO9hp6Z4e DXL3PlD0QsLSc27AkwzLEc/D3ZaqBq7ItvT9Pyg0z3Q+2dtLF00f9+663HVC2EUgP25J3xDd 496SIeYDTkEgbJ7WYR0HYm9uirSET3lDqOVh1xPqoy+U9zTtuA9NQHVGk+hPcoazSqEtLGBk YE2mm2wzX5q2uoyptseSNceJ+HE9L+z1KlWW63HhddgtRGhbP8pj42bKaUSrrfDUsicfeJf6 m1iJRu0SXYVlMruGUB1PvZQ3O7TsVfAGCv85pFipdgk8KQnlRFkYhUjLft0u7CL1rDGZWDDr NaNj54q2CX9zuSxBn9XDXvGKyzKEZ4NY1Jfw+TAMPCp4buawuOsjONi2X0DfivFY+ZsjAIcx qQMglPtKk/wBs7q2lvJ+pHpgvLhLZyGqzAvKM1sVtRJ5j+ARKA0w4pYs5a5ufqcfT7dN6TBk LXZeD9xlVic93Ju08JSUx2ozlcfxq+BVNyA+dtv7elXUZ2DrYwARAQABtCxHdXN0YXZvIEEu IFIuIFNpbHZhIDxndXN0YXZvQGVtYmVkZGVkb3IuY29tPokCPQQTAQgAJwUCWywcDAIbIwUJ CWYBgAULCQgHAgYVCAkKCwIEFgIDAQIeAQIXgAAKCRBHBbTLRwbbMZ6tEACk0hmmZ2FWL1Xi l/bPqDGFhzzexrdkXSfTTZjBV3a+4hIOe+jl6Rci/CvRicNW4H9yJHKBrqwwWm9fvKqOBAg9 obq753jydVmLwlXO7xjcfyfcMWyx9QdYLERTeQfDAfRqxir3xMeOiZwgQ6dzX3JjOXs6jHBP cgry90aWbaMpQRRhaAKeAS14EEe9TSIly5JepaHoVdASuxklvOC0VB0OwNblVSR2S5i5hSsh ewbOJtwSlonsYEj4EW1noQNSxnN/vKuvUNegMe+LTtnbbocFQ7dGMsT3kbYNIyIsp42B5eCu JXnyKLih7rSGBtPgJ540CjoPBkw2mCfhj2p5fElRJn1tcX2McsjzLFY5jK9RYFDavez5w3lx JFgFkla6sQHcrxH62gTkb9sUtNfXKucAfjjCMJ0iuQIHRbMYCa9v2YEymc0k0RvYr43GkA3N PJYd/vf9vU7VtZXaY4a/dz1d9dwIpyQARFQpSyvt++R74S78eY/+lX8wEznQdmRQ27kq7BJS R20KI/8knhUNUJR3epJu2YFT/JwHbRYC4BoIqWl+uNvDf+lUlI/D1wP+lCBSGr2LTkQRoU8U 64iK28BmjJh2K3WHmInC1hbUucWT7Swz/+6+FCuHzap/cjuzRN04Z3Fdj084oeUNpP6+b9yW e5YnLxF8ctRAp7K4yVlvA7kCDQRbLBwMARAAsHCE31Ffrm6uig1BQplxMV8WnRBiZqbbsVJB H1AAh8tq2ULl7udfQo1bsPLGGQboJSVN9rckQQNahvHAIK8ZGfU4Qj8+CER+fYPp/MDZj+t0 DbnWSOrG7z9HIZo6PR9z4JZza3Hn/35jFggaqBtuydHwwBANZ7A6DVY+W0COEU4of7CAahQo 5NwYiwS0lGisLTqks5R0Vh+QpvDVfuaF6I8LUgQR/cSgLkR//V1uCEQYzhsoiJ3zc1HSRyOP otJTApqGBq80X0aCVj1LOiOF4rrdvQnj6iIlXQssdb+WhSYHeuJj1wD0ZlC7ds5zovXh+FfF l5qH5RFY/qVn3mNIVxeO987WSF0jh+T5ZlvUNdhedGndRmwFTxq2Li6GNMaolgnpO/CPcFpD jKxY/HBUSmaE9rNdAa1fCd4RsKLlhXda+IWpJZMHlmIKY8dlUybP+2qDzP2lY7kdFgPZRU+e zS/pzC/YTzAvCWM3tDgwoSl17vnZCr8wn2/1rKkcLvTDgiJLPCevqpTb6KFtZosQ02EGMuHQ I6Zk91jbx96nrdsSdBLGH3hbvLvjZm3C+fNlVb9uvWbdznObqcJxSH3SGOZ7kCHuVmXUcqoz ol6ioMHMb+InrHPP16aVDTBTPEGwgxXI38f7SUEn+NpbizWdLNz2hc907DvoPm6HEGCanpcA EQEAAYkCJQQYAQgADwUCWywcDAIbDAUJCWYBgAAKCRBHBbTLRwbbMdsZEACUjmsJx2CAY+QS UMebQRFjKavwXB/xE7fTt2ahuhHT8qQ/lWuRQedg4baInw9nhoPE+VenOzhGeGlsJ0Ys52sd XvUjUocKgUQq6ekOHbcw919nO5L9J2ejMf/VC/quN3r3xijgRtmuuwZjmmi8ct24TpGeoBK4 WrZGh/1hAYw4ieARvKvgjXRstcEqM5thUNkOOIheud/VpY+48QcccPKbngy//zNJWKbRbeVn imua0OpqRXhCrEVm/xomeOvl1WK1BVO7z8DjSdEBGzbV76sPDJb/fw+y+VWrkEiddD/9CSfg fBNOb1p1jVnT2mFgGneIWbU0zdDGhleI9UoQTr0e0b/7TU+Jo6TqwosP9nbk5hXw6uR5k5PF 8ieyHVq3qatJ9K1jPkBr8YWtI5uNwJJjTKIA1jHlj8McROroxMdI6qZ/wZ1ImuylpJuJwCDC ORYf5kW61fcrHEDlIvGc371OOvw6ejF8ksX5+L2zwh43l/pKkSVGFpxtMV6d6J3eqwTafL86 YJWH93PN+ZUh6i6Rd2U/i8jH5WvzR57UeWxE4P8bQc0hNGrUsHQH6bpHV2lbuhDdqo+cM9eh GZEO3+gCDFmKrjspZjkJbB5Gadzvts5fcWGOXEvuT8uQSvl+vEL0g6vczsyPBtqoBLa9SNrS VtSixD1uOgytAP7RWS474w== Message-ID: <52a533e5-f106-db5f-35f7-2dd85672f541@embeddedor.com> Date: Mon, 15 Apr 2019 14:35:17 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190326183202.GA17285@embeddedor> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit 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 - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.55.242 X-Source-L: No X-Exim-ID: 1hG7Nu-000A88-5G X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: ([192.168.43.131]) [189.250.55.242]:52672 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 4 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, Friendly ping: Who can take this? Thanks -- Gustavo On 3/26/19 1:32 PM, Gustavo A. R. Silva wrote: > header->number and i are 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/isa/wavefront/wavefront_synth.c:792 wavefront_send_patch() warn: potential spectre issue 'dev->patch_status' [w] (local cap) > sound/isa/wavefront/wavefront_synth.c:819 wavefront_send_program() warn: potential spectre issue 'dev->prog_status' [w] (local cap) > sound/isa/wavefront/wavefront_synth.c:1197 wavefront_send_alias() warn: potential spectre issue 'dev->sample_status' [w] > sound/isa/wavefront/wavefront_synth.c:1248 wavefront_send_multisample() warn: potential spectre issue 'dev->sample_status' [w] > sound/isa/wavefront/wavefront_synth.c:1548 wavefront_synth_control() warn: potential spectre issue 'dev->sample_status' [r] (local cap) > > Fix this by sanitizing header->number and i before using them to index > dev->patch_status, dev->prog_status, dev->sample_status. > > 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 > --- > sound/isa/wavefront/wavefront_synth.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/sound/isa/wavefront/wavefront_synth.c b/sound/isa/wavefront/wavefront_synth.c > index 0b1e4b34b299..a78e125dfdf9 100644 > --- a/sound/isa/wavefront/wavefront_synth.c > +++ b/sound/isa/wavefront/wavefront_synth.c > @@ -31,6 +31,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -788,6 +789,8 @@ wavefront_send_patch (snd_wavefront_t *dev, wavefront_patch_info *header) > > if (header->number >= ARRAY_SIZE(dev->patch_status)) > return -EINVAL; > + header->number = array_index_nospec(header->number, > + ARRAY_SIZE(dev->patch_status)); > > dev->patch_status[header->number] |= WF_SLOT_FILLED; > > @@ -815,6 +818,8 @@ wavefront_send_program (snd_wavefront_t *dev, wavefront_patch_info *header) > > if (header->number >= ARRAY_SIZE(dev->prog_status)) > return -EINVAL; > + header->number = array_index_nospec(header->number, > + ARRAY_SIZE(dev->prog_status)); > > dev->prog_status[header->number] = WF_SLOT_USED; > > @@ -1194,6 +1199,11 @@ wavefront_send_alias (snd_wavefront_t *dev, wavefront_patch_info *header) > return -EIO; > } > > + if (header->number >= ARRAY_SIZE(dev->sample_status)) > + return -EINVAL; > + header->number = array_index_nospec(header->number, > + ARRAY_SIZE(dev->sample_status)); > + > dev->sample_status[header->number] = (WF_SLOT_FILLED|WF_ST_ALIAS); > > return (0); > @@ -1245,6 +1255,12 @@ wavefront_send_multisample (snd_wavefront_t *dev, wavefront_patch_info *header) > return -EIO; > } > > + if (header->number >= ARRAY_SIZE(dev->sample_status)) { > + kfree(msample_hdr); > + return -EINVAL; > + } > + header->number = array_index_nospec(header->number, > + ARRAY_SIZE(dev->sample_status)); > dev->sample_status[header->number] = (WF_SLOT_FILLED|WF_ST_MULTISAMPLE); > > kfree(msample_hdr); > @@ -1545,6 +1561,7 @@ wavefront_synth_control (snd_wavefront_card_t *acard, > wc->status = EINVAL; > return -EINVAL; > } > + i = array_index_nospec(i, WF_MAX_SAMPLE); > wc->rbuf[0] = dev->sample_status[i]; > wc->status = 0; > return 0; >