From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=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=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 9DD80C433FF for ; Sat, 27 Jul 2019 09:30:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 61B722080C for ; Sat, 27 Jul 2019 09:30:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YBfh5b4c" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728269AbfG0Jae (ORCPT ); Sat, 27 Jul 2019 05:30:34 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:39595 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727885AbfG0Jad (ORCPT ); Sat, 27 Jul 2019 05:30:33 -0400 Received: by mail-pg1-f193.google.com with SMTP id u17so25888776pgi.6; Sat, 27 Jul 2019 02:30:33 -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=z5sjwqVGCxUQk+QSQ9chKyttBvfdYpP7hwc20jtvK+s=; b=YBfh5b4c27FdX9goY2NwNFVVkc7/LBvWciAxEdHe5TqJ91KWXuQkW6IJ2tt38Y0Afb rGT7GA1eMt6XSzc1Cmf5PvyD+4rnLQb6XwnjbYIQZGP38tGqhzv5qpbjsewYqSvvySbr Qwf0FqLvl4UvYL+7OK4cRrmMlfG4EImnLM4DRiHYjqoFuqUSlIx8kUahVK2I7NCz5B7S VuFvu5Jfbm/nHvLr+7bY1QHFEt39tYg3emOfOFg+mTwT+4rvTzaG9rrVHo6HupPuB3fg vTXUe9CBC1QJpG7YsInSTHkbffOGS7hUZkLW2m7AO7N9ZdbCZQtwA45PsjwFa6xSshNV JaDw== 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=z5sjwqVGCxUQk+QSQ9chKyttBvfdYpP7hwc20jtvK+s=; b=tLvNVIvb9FWTZwsDgmeKLFpIZ3+JMo+OPcCBB9FLHb4jLkAMAPCFg/U8IK2qOTITqi 2vs0QnUwQPQbvguzYmyrTfQVxcQ45TT2U6/q6a+seveXKWoHvaSPYMSBaQgf0qNjRF5H vo4D9rKyksw8qGW+vCq3rA4YZTeCFaqq6nXidx/xxsiigbiNOjz7n6kgz1IsnNO2WTWX 2rbfyQ/qHGvfPhfJAiv9MLVHxwZOD9u0OmEdviZf1jRecRvsh6FkeLR5Ud1kbWlQsFTK +pQv+skmfW5vX8VC638CezT1++m7dlr+CnOXvcN2Z5BGsvIAiiUPvXTN9EMJA+Wdxb+K rRWg== X-Gm-Message-State: APjAAAU9WkSdYya1KMvFHzRqHZYBOiHjhRA0cWRvDS/qE0N2daZgcBnW kXVwwFchQGl+Qvp8csIM8jE= X-Google-Smtp-Source: APXvYqy7WYLMlwSTVgB+dPwq8qrugVlz8KAywUvi0p/+dVAWFow6ZnujVnwVJPvmTOtHll1h9oSvtA== X-Received: by 2002:aa7:8804:: with SMTP id c4mr26416099pfo.65.1564219833191; Sat, 27 Jul 2019 02:30:33 -0700 (PDT) Received: from oslab.tsinghua.edu.cn ([2402:f000:4:72:808::3ca]) by smtp.gmail.com with ESMTPSA id i137sm53435357pgc.4.2019.07.27.02.30.31 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 27 Jul 2019 02:30:32 -0700 (PDT) From: Jia-Ju Bai To: vkoul@kernel.org, dan.j.williams@intel.com Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] dma: mv_xor: Fix a possible null-pointer dereference in mv_xor_prep_dma_xor() Date: Sat, 27 Jul 2019 17:30:27 +0800 Message-Id: <20190727093027.11781-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.0 Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org In mv_xor_prep_dma_xor(), there is an if statement on line 577 to check whether sw_desc is NULL: if (sw_desc) When sw_desc is NULL, it is used on line 594: dev_dbg(..., sw_desc, &sw_desc->async_tx); Thus, a possible null-pointer dereference may occur. To fix this bug, sw_desc is checked before being used. This bug is found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai --- drivers/dma/mv_xor.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c index 0ac8e7b34e12..08c0b2a9eb32 100644 --- a/drivers/dma/mv_xor.c +++ b/drivers/dma/mv_xor.c @@ -589,9 +589,11 @@ mv_xor_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, } } - dev_dbg(mv_chan_to_devp(mv_chan), - "%s sw_desc %p async_tx %p \n", - __func__, sw_desc, &sw_desc->async_tx); + if (sw_desc) { + dev_dbg(mv_chan_to_devp(mv_chan), + "%s sw_desc %p async_tx %p \n", + __func__, sw_desc, &sw_desc->async_tx); + } return sw_desc ? &sw_desc->async_tx : NULL; } -- 2.17.0