From patchwork Thu Nov 19 01:52:18 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: 11916393 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=-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 B0892C64E7D for ; Thu, 19 Nov 2020 01:52:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C314246CA for ; Thu, 19 Nov 2020 01:52:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hiJ1JsBn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727706AbgKSBw1 (ORCPT ); Wed, 18 Nov 2020 20:52:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60278 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727265AbgKSBw1 (ORCPT ); Wed, 18 Nov 2020 20:52:27 -0500 Received: from mail-pl1-x641.google.com (mail-pl1-x641.google.com [IPv6:2607:f8b0:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 37874C0613D4; Wed, 18 Nov 2020 17:52:27 -0800 (PST) Received: by mail-pl1-x641.google.com with SMTP id s2so2061435plr.9; Wed, 18 Nov 2020 17:52:27 -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=O3ThiUwvLYqwNqLXRXRAUrUNjVW2CgIY+DR5znXz6Ck=; b=hiJ1JsBn/XfhJvTqOg5P+dJhfHx+stklBu/B2NHegIqQsB9wnc2pQk/h8lYQ3NIOvW vqDpbL1dF+2kaESBd2miRG232EAgJVT/BK8ptTrePs0lONFzRfewbt7f00PxujiLtyOn bd2Pf9vSrr0gOfcxO+Em7ut9u1ViFzrw0uD8f9iPqIHAujRTg9Yh0tj4kEosj2u1N8t1 3pxhHQymoAb6XZd1xtrAsBkr5KkYQZuJZVz8cFSVl/dqLYMwai+jP/hHZ5GtosnwTdpx HACeMLml3N4jCBSZ5JDlFBQ63CZgB6io2axKP9tI5XDIeAqx6R808vVdLQ8Pyj1JuN++ +J4A== 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=O3ThiUwvLYqwNqLXRXRAUrUNjVW2CgIY+DR5znXz6Ck=; b=MunXofqeX16ntKLI8lsyBd2L/btu3auFAcNpOKCUVqmsnxkKdem+k0L8T8GX7sBxJH 8uR/U7RFOGVnbE1OV4J6mj6Ghi2hQqDycw9x7wDI4Fvw9L3It22nY/VPtWkc4IH5/q7f 8ltArNjFBTNh20O6ynhUHQ/A5vFh6QopTfgAjCnswT7dH5id6ZHyrLGP0/BNqQEpzmFG tTFNaBrfyqrgNyfITQAwwNM08WLZ26+njSeT7OPH7MyAYzN07nRCuB99dRxaroujR8L2 2zus+bMd77aT+AWmnbC23L9YKAAiJklpXSdvT8QA9a79x7e3/7wrHh7UxR2XIXp3ngmL 0QZQ== X-Gm-Message-State: AOAM533TnfFgdiX4lfYDMWTopjpLuNpvpTS6WWWapBDaemouoRSp0tfk CaL5UYQ6U8EdjCw4f0ehoEz9oXDbfyxfrQ== X-Google-Smtp-Source: ABdhPJywqIvy+2ZVL/7mOsL29r7EzB+mlhB406Ko6cPrwXDRr0gTX3vUKy9dCGxgO3W2gaNBUi1BVw== X-Received: by 2002:a17:902:9f90:b029:d9:da48:6021 with SMTP id g16-20020a1709029f90b02900d9da486021mr600256plq.81.1605750746645; Wed, 18 Nov 2020 17:52:26 -0800 (PST) Received: from localhost.localdomain ([45.56.153.149]) by smtp.gmail.com with ESMTPSA id r3sm3976638pjl.23.2020.11.18.17.52.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Nov 2020 17:52:25 -0800 (PST) From: Jia-Ju Bai To: pkshih@realtek.com, kvalo@codeaurora.org, davem@davemloft.net, kuba@kernel.org, Larry.Finger@lwfinger.net Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH v2 4/4 resend] rtlwifi: rtl8723ae: avoid accessing the data mapped to streaming DMA Date: Thu, 19 Nov 2020 09:52:18 +0800 Message-Id: <20201119015218.12220-1-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 rtl8723e_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on line 531: dma_addr_t mapping = dma_map_single(..., skb->data, ...); On line 534, 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 535: __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 --- v2: * Use "rtlwifi" as subject prefix and have all rtlwifi patches in the same pathset. Thank Ping and Larry for good advice. --- drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c index e3ee91b7ea8d..340b3d68a54e 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8723ae/trx.c @@ -528,12 +528,12 @@ void rtl8723e_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");