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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 3B644C47257 for ; Sat, 9 May 2020 05:49:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 182DF21582 for ; Sat, 9 May 2020 05:49:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="KWpBbfDN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728957AbgEIFtT (ORCPT ); Sat, 9 May 2020 01:49:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728952AbgEIFtT (ORCPT ); Sat, 9 May 2020 01:49:19 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC1D3C061A0C for ; Fri, 8 May 2020 22:49:18 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id fu13so5243853pjb.5 for ; Fri, 08 May 2020 22:49:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=UTsYNNg6/ImkBFmD+Mx+o8hefWjZHqjjHqjvwNd6AaI=; b=KWpBbfDNThXu0samEeWM29vOiWvpu8bLxOq8vtogPK4chc1jyMzdaIKh2bH3uXnPOJ O1/Z9EivVp8xAYBnw92K8gKiR9Jx97wf7m86eWMtdj91DMsdiV41QkFXwkfpzmaoG0iL ox+ZjcuLM4UJegbJ67vEC8n/GIV3Ilkq5ptfOAnRptAjC94Wk5ATFS0VzKiNz2PtaRtw XNtQt0bVmYUaeVm7KvwzHY3xEzVrCgHVK5xxmk1QlkhLJt7+5XwK9+JfT3BsRoEet2H4 zPYFvlGMT73gmKk7Udha74SQogviTkysjoKmNK9EtzzRumTgUD0oWPr+84HkXuIPLPVr r7ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=UTsYNNg6/ImkBFmD+Mx+o8hefWjZHqjjHqjvwNd6AaI=; b=ciVMTpPR9BJiy2zOkEREQp8uMhNKbtH795rFJYYEK+qaKfABQWJhpmpf3fzpp7v8Vb bFerpMAhQn3GCuibPwP52QY0rg1wgTUeKtkweHNZLlwLda7OKb+mWW7ebghT0XrVPl3p +dluIUFRh4FT+1ZoeK2HAMTNYpFzFuDwIbdlHFPUVfuVSV6P4mkggojNmzbkeQoGG4H/ XV/Swi5NsL61iccRgumqHaCzowswuMEitI3RA/hzfGng6vIEdmMfooYTJPh1OLPLeLQi 3WHbf/5WyWEQdy1jUnX+sg0x6NJAFMkBgpIQXFmnemVXKxTGFWZP5nj8Lz/Mg89iow5N yqKQ== X-Gm-Message-State: AGi0PuYWXbZYlZfpYeeLH4msCljl+IAk4sRmvl21EP82mpY+ZN1uT2XH Ry/1JSl4C5TT1DLyP5qZ90eQ X-Google-Smtp-Source: APiQypLLc1C6DFA08CoY4IdmL7MfLAuWYGg5shRu8jEKGB2/9SEa/nFSEdsrrOtjaYE1m/feRk2kzA== X-Received: by 2002:a17:90a:8c9:: with SMTP id 9mr9910633pjn.183.1589003358252; Fri, 08 May 2020 22:49:18 -0700 (PDT) Received: from Mani-XPS-13-9360 ([2409:4072:6e0c:55d2:2cb4:da01:ad1e:6ad9]) by smtp.gmail.com with ESMTPSA id gv7sm3824144pjb.16.2020.05.08.22.49.14 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Fri, 08 May 2020 22:49:17 -0700 (PDT) Date: Sat, 9 May 2020 11:19:11 +0530 From: Manivannan Sadhasivam To: Bhaumik Bhatt Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, hemantk@codeaurora.org, jhugo@codeaurora.org Subject: Re: [PATCH v7 4/8] bus: mhi: core: Read transfer length from an event properly Message-ID: <20200509054911.GD5845@Mani-XPS-13-9360> References: <1588991208-26928-1-git-send-email-bbhatt@codeaurora.org> <1588991208-26928-5-git-send-email-bbhatt@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1588991208-26928-5-git-send-email-bbhatt@codeaurora.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Fri, May 08, 2020 at 07:26:44PM -0700, Bhaumik Bhatt wrote: > From: Hemant Kumar > > When MHI Driver receives an EOT event, it reads xfer_len from the > event in the last TRE. The value is under control of the MHI device > and never validated by Host MHI driver. The value should never be > larger than the real size of the buffer but a malicious device can > set the value 0xFFFF as maximum. This causes driver to memory > overflow (both read or write). Fix this issue by reading minimum of > transfer length from event and the buffer length provided. > > Signed-off-by: Hemant Kumar > Signed-off-by: Bhaumik Bhatt > Reviewed-by: Jeffrey Hugo Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > drivers/bus/mhi/core/main.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c > index 30798ec..6a80666 100644 > --- a/drivers/bus/mhi/core/main.c > +++ b/drivers/bus/mhi/core/main.c > @@ -514,7 +514,10 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl, > mhi_cntrl->unmap_single(mhi_cntrl, buf_info); > > result.buf_addr = buf_info->cb_buf; > - result.bytes_xferd = xfer_len; > + > + /* truncate to buf len if xfer_len is larger */ > + result.bytes_xferd = > + min_t(u16, xfer_len, buf_info->len); > mhi_del_ring_element(mhi_cntrl, buf_ring); > mhi_del_ring_element(mhi_cntrl, tre_ring); > local_rp = tre_ring->rp; > @@ -598,7 +601,9 @@ static int parse_rsc_event(struct mhi_controller *mhi_cntrl, > > result.transaction_status = (ev_code == MHI_EV_CC_OVERFLOW) ? > -EOVERFLOW : 0; > - result.bytes_xferd = xfer_len; > + > + /* truncate to buf len if xfer_len is larger */ > + result.bytes_xferd = min_t(u16, xfer_len, buf_info->len); > result.buf_addr = buf_info->cb_buf; > result.dir = mhi_chan->dir; > > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project