From patchwork Wed Nov 18 01:53:14 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: 327802 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 DF2A0C56202 for ; Wed, 18 Nov 2020 01:54:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B61A2151B for ; Wed, 18 Nov 2020 01:54:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iOOTgarB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726205AbgKRBxx (ORCPT ); Tue, 17 Nov 2020 20:53:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725730AbgKRBxx (ORCPT ); Tue, 17 Nov 2020 20:53:53 -0500 Received: from mail-pj1-x1042.google.com (mail-pj1-x1042.google.com [IPv6:2607:f8b0:4864:20::1042]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C634C061A48; Tue, 17 Nov 2020 17:53:51 -0800 (PST) Received: by mail-pj1-x1042.google.com with SMTP id js21so219902pjb.0; Tue, 17 Nov 2020 17:53:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=t5eReXO4wqmdOiCBF4R3AZcbfxasgeFRgSN87jtfTOA=; b=iOOTgarBSRRV3nOEIu7RPO2lJzpE7H0bWf/Qkv32Dwl6ecP2lZqAw7+9hfCztF88lC His2eJEuigwDBhcb9hfT6xTOzQiZwORJCx67+WrAQGLSwIqpWOuZ/VX6Gh6/HkC+2aRq KEf67tHBbfprzTe+J1pEJQbnO6bdDHVf8SoIy2krfHhWsaZ31xIe7HbqPdAt534yxBIe DbP/bXXy27S9bOantElC6qzqEDgBXRGKel3B4MOdILOz7TODEmn06lLxC4+eOiJz3JR9 y/M1GrVNQgxFTVtVuQAs7lfPhQVHTUlB8GTpqHKICauG/J6euAUjJMSbS1Jg1NS//FiR Y9gQ== 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=t5eReXO4wqmdOiCBF4R3AZcbfxasgeFRgSN87jtfTOA=; b=c3Sd/NzeGJwMwNE5NgxeHweviNkDG1Mz7ejc1gHyTzlIBa92mpQ5EG5WUeM3X78fPm Trn1lSpZj4fWJ5ZYWxUk8AZKhDZ6ZjNJfDNSjps8pwZD0FYaH8t3TE6ComU4ppeExNFe 72yKU/v/ZkWmU73TDs9s+ocOhE3ouXa0M+sB8EMtKoXAg6zdk9DNOtmEnwX1Euka4kp0 ReWD08ym3PLE2jvjCDITvKYxk+4WMMNx7GyjF2MkWGre9ykCAcdPaHljSuJ+3AqaBZMX i91p3NV9YPq90+diHdP3jtPm2vZzTTBnmhrlsNmy1omoxjWvTU5MM/9J9tR0eefdZphR BqTw== X-Gm-Message-State: AOAM530FjbTsVYtaLZkXp+p5O4a3skc5JhJzoakufqJ0pM8dp8d8z3Fj IiO3zw1jQGBofqNFJfSr4i8= X-Google-Smtp-Source: ABdhPJxTtKOhfudWJ+Y1l0w8jEU3rSWDhUb1E21+wQSdIi35mopiq4+sofDFLHqLhSuaxds8II+/Lg== X-Received: by 2002:a17:90a:f0c7:: with SMTP id fa7mr1876767pjb.3.1605664430920; Tue, 17 Nov 2020 17:53:50 -0800 (PST) Received: from oslab.tsinghua.edu.cn ([166.111.139.137]) by smtp.gmail.com with ESMTPSA id t32sm21430494pgl.0.2020.11.17.17.53.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Nov 2020 17:53:50 -0800 (PST) From: Jia-Ju Bai To: pkshih@realtek.com, kvalo@codeaurora.org, davem@davemloft.net, kuba@kernel.org Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH v2 1/4] rtlwifi: rtl8188ee: avoid accessing the data mapped to streaming DMA Date: Wed, 18 Nov 2020 09:53:14 +0800 Message-Id: <20201118015314.4979-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org In 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 --- drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c index b9775eec4c54..c948dafa0c80 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c @@ -674,12 +674,12 @@ void rtl88ee_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");