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=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 9A878C56201 for ; Tue, 24 Nov 2020 15:07:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32F6B2086A for ; Tue, 24 Nov 2020 15:07:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="a8Y6m36+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389468AbgKXPHM (ORCPT ); Tue, 24 Nov 2020 10:07:12 -0500 Received: from z5.mailgun.us ([104.130.96.5]:27146 "EHLO z5.mailgun.us" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730771AbgKXPHL (ORCPT ); Tue, 24 Nov 2020 10:07:11 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1606230431; h=Date: Message-Id: Cc: To: References: In-Reply-To: From: Subject: Content-Transfer-Encoding: MIME-Version: Content-Type: Sender; bh=LsuBxM5cnW7TMS67JlUwgXhRD1y+7X2AiH5GtE5Sr0g=; b=a8Y6m36+Asa0mNdzd308O65dN0ntqCfRqWddC+xBNPDIv9V12B2r3crWRHD3mradK2AzF3L+ q7A41hX6XeAhdCzf3HzEXxnWoyhcBo01N85k33uJU2kK1+iYhHfPTWLoY1wESHpE/YNC9u6s fPGAescshWJWXu65Uw8ZRPZobcw= X-Mailgun-Sending-Ip: 104.130.96.5 X-Mailgun-Sid: WyJiZjI2MiIsICJuZXRkZXZAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n04.prod.us-east-1.postgun.com with SMTP id 5fbd21971b731a5d9c4090fd (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 24 Nov 2020 15:07:03 GMT Sender: kvalo=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id C911EC43461; Tue, 24 Nov 2020 15:07:02 +0000 (UTC) Received: from potku.adurom.net (88-114-240-156.elisa-laajakaista.fi [88.114.240.156]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: kvalo) by smtp.codeaurora.org (Postfix) with ESMTPSA id 42B4BC433ED; Tue, 24 Nov 2020 15:06:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 42B4BC433ED Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=kvalo@codeaurora.org Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [PATCH v2 1/4 resend] rtlwifi: rtl8188ee: avoid accessing the data mapped to streaming DMA From: Kalle Valo In-Reply-To: <20201119015127.12033-1-baijiaju1990@gmail.com> References: <20201119015127.12033-1-baijiaju1990@gmail.com> To: Jia-Ju Bai Cc: pkshih@realtek.com, davem@davemloft.net, kuba@kernel.org, Larry.Finger@lwfinger.net, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai User-Agent: pwcli/0.1.0-git (https://github.com/kvalo/pwcli/) Python/3.5.2 Message-Id: <20201124150702.C911EC43461@smtp.codeaurora.org> Date: Tue, 24 Nov 2020 15:07:02 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Jia-Ju Bai wrote: > In rtl88ee_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on > line 677: > dma_addr_t mapping = dma_map_single(..., skb->data, ...); > > On line 680, skb->data is assigned to hdr after cast: > struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data); > > Then hdr->frame_control is accessed on line 681: > __le16 fc = hdr->frame_control; > > This DMA access may cause data inconsistency between CPU and hardwre. > > To fix this bug, hdr->frame_control is accessed before the DMA mapping. > > Signed-off-by: Jia-Ju Bai 4 patches applied to wireless-drivers-next.git, thanks. 6df3c293d284 rtlwifi: rtl8188ee: avoid accessing the data mapped to streaming DMA c7ba0ea0df37 rtlwifi: rtl8192ce: avoid accessing the data mapped to streaming DMA ff7654833894 rtlwifi: rtl8192de: avoid accessing the data mapped to streaming DMA 8b2c13b2e5da rtlwifi: rtl8723ae: avoid accessing the data mapped to streaming DMA -- https://patchwork.kernel.org/project/linux-wireless/patch/20201119015127.12033-1-baijiaju1990@gmail.com/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches