From patchwork Thu Nov 19 01:51:27 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: 329660 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=ham 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 C83AAC63798 for ; Thu, 19 Nov 2020 01:51:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 678D4246B0 for ; Thu, 19 Nov 2020 01:51:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="B68UiTUZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727395AbgKSBvk (ORCPT ); Wed, 18 Nov 2020 20:51:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726413AbgKSBvk (ORCPT ); Wed, 18 Nov 2020 20:51:40 -0500 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 762F1C0613D4; Wed, 18 Nov 2020 17:51:38 -0800 (PST) Received: by mail-pf1-x444.google.com with SMTP id y7so2890137pfq.11; Wed, 18 Nov 2020 17:51:38 -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=3r5FZrPv+WHArPH9yqncOxdfTiMaYsbEsDIytgtTf2k=; b=B68UiTUZfXssmJtMqOe1VvpB4J8RMb+KXeHqyINfBPaG9OGRrl9a3ALtiPByvZFTcy R7CUYBAq4tmfgEzDBc8Sc0JnIe1obvw622jeEDHSuh8E6FNqVWB0kXo9ABMY6XRZ707R XOflQwYUMSm2U9uiJelSrw1Q22h+ZCRUb4dyWx8jGQ++bdQ1fM2io0rgxAIGCvdNhgLV cYxu4ZZIi++mocXnbuOvRUMq+h1/YQn5x6fErsAqbXnFonqwQVnlgPtVQEsQ4qJSs7SS I0b6i5jXM7IZ0TSbzDAbNOtMboVrUSuJbeMeU3CDB3aqexqtCxhUGz3w72suGnqZ8HBB M41g== 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=3r5FZrPv+WHArPH9yqncOxdfTiMaYsbEsDIytgtTf2k=; b=ldYXqNNeM51KB0tzQwVoaAOkdlg5lv4U3YV+lDydwon+6n1KlP4FgEJmUJHVrTmsHJ PuJpaAH9rYhGGUQwgc88zS66geVBvNG9wVW640tyIjToMeZ65kM9/ikgI8K03RUJevDy UKSHAs8taMI1agbswFDKhfxsUl8ZY4L9gL1s7y5Cbp+NHXg0Qg7zqxQ2XdhqM8AZ11U5 5NP4Exlrhfixp/n9S9pb7sbQlFFu6JGDaEcuyrrEVCO9AGvTHUVabjXnisxfS8IZwnjY MF0YYDMD+pNd+6kDpj9ouCRZu6Lvn6CqS/YFPXHNcSlSoTYYQ0JrjoWe3uED2v2mgUa0 F5HA== X-Gm-Message-State: AOAM5317B0en3eD3l/0pWR+MLMP+37Uu7s6V//zEc/WlUDh3DPSm3AWo WYC7MIGBZ8FHG17zUnOAlcs= X-Google-Smtp-Source: ABdhPJxn1hPFjguU/lx7e1TERyJiuCSd2U9KvvRdrHXrqmCBn6zNigbbZIltJmjpFG3kOv7JBO0UDw== X-Received: by 2002:aa7:981a:0:b029:18b:490f:77d9 with SMTP id e26-20020aa7981a0000b029018b490f77d9mr7033443pfl.46.1605750697927; Wed, 18 Nov 2020 17:51:37 -0800 (PST) Received: from localhost.localdomain ([45.56.153.149]) by smtp.gmail.com with ESMTPSA id e201sm27003636pfh.73.2020.11.18.17.51.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Nov 2020 17:51:37 -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 1/4 resend] rtlwifi: rtl8188ee: avoid accessing the data mapped to streaming DMA Date: Thu, 19 Nov 2020 09:51:27 +0800 Message-Id: <20201119015127.12033-1-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 --- 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/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");