From patchwork Mon Oct 19 03:09:31 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: 11843539 X-Patchwork-Delegate: kuba@kernel.org 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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 B1EE2C43457 for ; Mon, 19 Oct 2020 03:09:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F81922260 for ; Mon, 19 Oct 2020 03:09:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WHAkofSv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731351AbgJSDJk (ORCPT ); Sun, 18 Oct 2020 23:09:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728660AbgJSDJj (ORCPT ); Sun, 18 Oct 2020 23:09:39 -0400 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6884C061755; Sun, 18 Oct 2020 20:09:39 -0700 (PDT) Received: by mail-pl1-x644.google.com with SMTP id p11so4260207pld.5; Sun, 18 Oct 2020 20:09:39 -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=kE2vWbri16fQXY9rpZDoR0E3WjS1MfyWuTMn6iwlvi0=; b=WHAkofSvpxnAin+a9XCsOwK2Kt2QArHkMpNTywDyT48/doTUs6TsMfp8QLuFzxr814 cW2JZKU19OpbwuFvdTO0kjhi6hERXdaCG7K12NitdIBzYel5C2gHd+zDh4oEHfhRdVza FArR5+4VGLXlIrfQDEIsOosDsVLbHOJYH6PZzdeRQl0dk9GtWFAOSFGSRnc2ekMY/1Lu RuK8TdbjZn7xJzobRfAmuzSjtoqF79rauFg8Xg4on30STPUqA6Z0reTBVMEzYmCDPSgf wrwW+iUyWzmpwfwjrqsF6y8NvpOkc/juQCVn3krDz/+BuxtuEt/wfQVwA+LvnocDjy+s nF2w== 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=kE2vWbri16fQXY9rpZDoR0E3WjS1MfyWuTMn6iwlvi0=; b=DHYkMH+5JPcelPa95J0HP0unK5YQ6gOk9vgFZAeQ9of9OAMtfSc8fi1cH2Q843FzwH qy97dfMghrMJGtK2MmAPcyRiN9DxmIxeL26fbpKunOGwOQywT/UWnNIIMwYdot3D0VLT BrVU0TqmUM6c/wfZpPpzKnTt6dzoey++pMBvR2hT+Kb9tagewZs0nG77goJpaLNrgrr0 XbVWpJMjVW8mibuWsUR/hmjdOusU9wKetn7X5eZHFHQT7ACEBUAA1F4sqXMJGzObJg+m y/svJ4c30u1FtdrEzifq8K6I+/pQgXh10uX86B6WbsZ+vKE1xjsFG2lASQ5f5bWS+lv7 +K0w== X-Gm-Message-State: AOAM530WwsGVHZspTBexm8InAs3U87x+m2Yg7X2jNFfw6hH9q4xdCT/p 1dRRKmjf0Ot+FONbTjGZL3gmpc8BPSo= X-Google-Smtp-Source: ABdhPJxyYMBR74lbDEbV+AxXZvOe9e8MKN+LBscIC266xnv+tOqvAZyr7iQcLPmHV4pm91sdxQjYGw== X-Received: by 2002:a17:90b:2389:: with SMTP id mr9mr15267215pjb.146.1603076979251; Sun, 18 Oct 2020 20:09:39 -0700 (PDT) Received: from oslab.tsinghua.edu.cn ([166.111.139.137]) by smtp.gmail.com with ESMTPSA id y65sm9796864pfy.57.2020.10.18.20.09.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 18 Oct 2020 20:09:38 -0700 (PDT) From: Jia-Ju Bai To: pkshih@realtek.com, kvalo@codeaurora.org, davem@davemloft.net, kuba@kernel.org, straube.linux@gmail.com, Larry.Finger@lwfinger.net, christophe.jaillet@wanadoo.fr Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] rtl8192ce: avoid accessing the data mapped to streaming DMA Date: Mon, 19 Oct 2020 11:09:31 +0800 Message-Id: <20201019030931.4796-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org In rtl92ce_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on line 530: dma_addr_t mapping = dma_map_single(..., skb->data, ...); On line 533, 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 534: __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/rtl8192ce/trx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c index c0635309a92d..4165175cf5c0 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c @@ -527,12 +527,12 @@ void rtl92ce_tx_fill_cmddesc(struct ieee80211_hw *hw, u8 fw_queue = QSLT_BEACON; __le32 *pdesc = (__le32 *)pdesc8; - 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; + 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");