From patchwork Wed Nov 18 01:54:18 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: 327801 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 DE7FFC6379F for ; Wed, 18 Nov 2020 01:54:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93BEA24248 for ; Wed, 18 Nov 2020 01:54:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LYfvQ9lI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726993AbgKRBy0 (ORCPT ); Tue, 17 Nov 2020 20:54:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725730AbgKRByZ (ORCPT ); Tue, 17 Nov 2020 20:54:25 -0500 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7DD66C061A48; Tue, 17 Nov 2020 17:54:25 -0800 (PST) Received: by mail-pj1-x1043.google.com with SMTP id h12so214963pjv.2; Tue, 17 Nov 2020 17:54:25 -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=+XVQiLhPjTZQE7BJhiPhjmEEz4RW+ut2EJwMRL1LH18=; b=LYfvQ9lIzEjwOb1CVUstMO/UfVPBBhU9xlsaQopp0IGnfbV4Ns2JSr1z786oJYHYri bd/sQt7CeWlUhRUP2iuTNjA2q3DTgGNdu8K+Lr4WrnPhR6VooyuhmbQ8MjeKBwAXpP54 sT7jT9QQFhWPUubPbQ4bzoIDw0tFntnsYMlmdxwxnmx5KWBfcPhr4j0a4KyJ5TpRLyGh pb4BP8ZUKMZnpzVjOrU/HoibDwgXmoAzg3z3k9oCENcDzGPLoSQ4B1KAbG8jU5AYoNcZ vxMEzjVQxkLNmFF31YrKaWebKf5bULIkoi4HTRcOnwXSBZWogjwc7a6+DVG5dljM2Xti GcTg== 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=Xf/X+CJ21ILwqjUC4pwWXW4XESU5O49LErf9l/XKcrGraxcRnQE3wNDzXbCL9R4SSH pvaSGvzyEIpppkpwJWwP0Ljv56qLj8mjRsXeRUUfVPicKWSuiSErQKbFqaqk0qi1aHhE 4TQ5HfxVq8c9KKTDFXUsbyQGJ8JCIa7VybWJrdVHiSq8PkPMs9Bc9HMkWB/OCVMc3Hxx eVu2+rk1dw8yi2q6l+vm2+QO/hrhiY6yqTyAbsAOScrgIDoep0hsfBZwn5NEDaF8GoPS C3rYH/7Atk3VO3f7NlDbFJPxOrFwjECtpQNL1M7sM5c6ZHfo9Bff1ec/xOrbiKYD8OpX UH2A== X-Gm-Message-State: AOAM532ujmU6k8k528o5XLX5wfKSRkBATYImZG9Y/2aJagHpZXks6XI8 aReCFYOebBmvLTgttaXQ2Ag= X-Google-Smtp-Source: ABdhPJyrs5SICFqofuIp7QcyHMO6bgLTzwDISjnQhdiB0ni+j5Egq/Zs1vhmZIq9KxyPBGyQVVw4Sw== X-Received: by 2002:a17:90b:241:: with SMTP id fz1mr1835713pjb.172.1605664465091; Tue, 17 Nov 2020 17:54:25 -0800 (PST) Received: from oslab.tsinghua.edu.cn ([166.111.139.137]) by smtp.gmail.com with ESMTPSA id w70sm22402883pfc.11.2020.11.17.17.54.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Nov 2020 17:54:24 -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 3/4] rtlwifi: rtl8192de: avoid accessing the data mapped to streaming DMA Date: Wed, 18 Nov 2020 09:54:18 +0800 Message-Id: <20201118015418.5122-1-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");