From patchwork Mon Oct 19 03:09:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 11843541 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C9D4C17C9 for ; Mon, 19 Oct 2020 03:10:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABED622263 for ; Mon, 19 Oct 2020 03:10:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ivzxwItr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731400AbgJSDKE (ORCPT ); Sun, 18 Oct 2020 23:10:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731344AbgJSDKD (ORCPT ); Sun, 18 Oct 2020 23:10:03 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17580C061755; Sun, 18 Oct 2020 20:10:03 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id 144so5158060pfb.4; Sun, 18 Oct 2020 20:10:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=+XVQiLhPjTZQE7BJhiPhjmEEz4RW+ut2EJwMRL1LH18=; b=ivzxwItr1V0tMdevDRrDJxFaJ0h4GBlAQjOS7Tleht1F+SPg0L0ZmyN9gygf/HRL9A UsIgI/d8St19CFdYfqWOcHlp95B+GBjdgE+P+V2F/JoFNud7wHjtKLpvAnlIR90lqW+U XCFZw7K4w+gbb04VuuLFXeb/yMzQDAOmgE2XkGSCKvDVn4fgT1YfGznOW9LcAZ0pXVt1 53d1t5ZSfbvxVBFET4OoE2AOBdg9YL/mUTioN0o0FLpQfsIZqlwPW2r/dIo5tOnfn1W5 x5wwmM5Glsco8lDt8tx2kcmrfoPVaGno+aQ6C4C+5/UERoIz5zCRmID+TJHclnsRDiMG jOzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=+XVQiLhPjTZQE7BJhiPhjmEEz4RW+ut2EJwMRL1LH18=; b=t1f4FgmsZh+r9uKL+DPxIdfkhrAFlqkmrI34fvjqUyDEdWQ+mEHsVIX0FGLFXLf4Xl UvgSDESuMqHLasJZjz+xAzi648a/vkrvKGQo7JE/ws0eMAKQJS0WwJiVO6SMeGRez+Br 6eb4w4FzZQJCnAphV2QiY6vQ4fJaj2PcSMQ7hipxj0WHdy+CEIFUtulf+BCYNpldC8jV dzD+5DH40ZygFpFPDsiPST0O+En3aSCWQI4YpO2ZMm3of62OadAznvBKZoUMGW87gd81 ++q2ta10meoJ237blMMFTEzVyzpjXycsp4dh7YZQu8NUbIDcsGLQ2FX57CS1YTxMpRhs gkaQ== X-Gm-Message-State: AOAM532C4lWdOWYRqycjol5rPHILZFsRcG+ZyEizL5FUPsLlZ6eUpt6S 3rSZPJ+Z/dkSN3LS74Sy9LA= X-Google-Smtp-Source: ABdhPJwZT3nkD/m1wrsgA0SYjoDx3q72J6JaWfNUMpv7VDRxu23FQ5fSYPf/HCmITnpAwIcFKa+2KQ== X-Received: by 2002:a62:1d57:0:b029:152:47a7:e04b with SMTP id d84-20020a621d570000b029015247a7e04bmr15073297pfd.48.1603077002656; Sun, 18 Oct 2020 20:10:02 -0700 (PDT) Received: from oslab.tsinghua.edu.cn ([166.111.139.137]) by smtp.gmail.com with ESMTPSA id ch21sm9863395pjb.24.2020.10.18.20.09.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 18 Oct 2020 20:10:02 -0700 (PDT) From: Jia-Ju Bai To: pkshih@realtek.com, kvalo@codeaurora.org, davem@davemloft.net, kuba@kernel.org, Larry.Finger@lwfinger.net, straube.linux@gmail.com, christophe.jaillet@wanadoo.fr Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] rtl8192de: avoid accessing the data mapped to streaming DMA Date: Mon, 19 Oct 2020 11:09:52 +0800 Message-Id: <20201019030952.4851-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org In rtl92de_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on line 667: dma_addr_t mapping = dma_map_single(..., skb->data, ...); On line 669, 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 670: __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 --- drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c index 8944712274b5..c02813fba934 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c @@ -664,12 +664,14 @@ void rtl92de_tx_fill_cmddesc(struct ieee80211_hw *hw, struct rtl_ps_ctl *ppsc = rtl_psc(rtlpriv); struct rtl_hal *rtlhal = rtl_hal(rtlpriv); u8 fw_queue = QSLT_BEACON; - dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, - skb->len, DMA_TO_DEVICE); + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data); __le16 fc = hdr->frame_control; __le32 *pdesc = (__le32 *)pdesc8; + dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, + skb->len, DMA_TO_DEVICE); + if (dma_mapping_error(&rtlpci->pdev->dev, mapping)) { rtl_dbg(rtlpriv, COMP_SEND, DBG_TRACE, "DMA mapping error\n");