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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 48F30C10F0E for ; Mon, 15 Apr 2019 19:19:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1312A20818 for ; Mon, 15 Apr 2019 19:19:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355987; bh=jiDGRekqCK1szeSFetkCi4HCXfZdwiexv7h/YqgrU14=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=g7dGiLyOqgXDSTU290EIbiO/P/JfhLIafl+WKvPhGITXbZiZb0+Li1xzT0Bnzx2Vs NOZgM7bZX76YZfgMGzdzrAITphMh4wTnkq33Ha8CZPQIU+EnxjuCG6SPIYwM2mJsRA 2AlkYXsYrut4CVI8noLhv1npaRfDEPjfjG0PGO/8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731527AbfDOTTq (ORCPT ); Mon, 15 Apr 2019 15:19:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:46476 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730078AbfDOTKR (ORCPT ); Mon, 15 Apr 2019 15:10:17 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2B25521905; Mon, 15 Apr 2019 19:10:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355416; bh=jiDGRekqCK1szeSFetkCi4HCXfZdwiexv7h/YqgrU14=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0yaRgEIggNLJP9eg2iCE8CkdRZY30Xmj+pRTOFqYsYtDasXfoH73kn0XqDtvup1M0 F3pZl/xUy9Pto+4bXSj4231u5xvpgxpeOtgMBDNe74nmZ1rhXqXmvDP26yqszL2xWn FxqRDkA19bRx8rBMFxd+kKE5xr07cXspUtcPO6qE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Li RongQing , Wang Li , Michal Kubecek , "David S. Miller" , Sasha Levin Subject: [PATCH 5.0 012/117] net: ethtool: not call vzalloc for zero sized memory request Date: Mon, 15 Apr 2019 20:59:42 +0200 Message-Id: <20190415183745.517114459@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183744.887851196@linuxfoundation.org> References: <20190415183744.887851196@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 3d8830266ffc28c16032b859e38a0252e014b631 ] NULL or ZERO_SIZE_PTR will be returned for zero sized memory request, and derefencing them will lead to a segfault so it is unnecessory to call vzalloc for zero sized memory request and not call functions which maybe derefence the NULL allocated memory this also fixes a possible memory leak if phy_ethtool_get_stats returns error, memory should be freed before exit Signed-off-by: Li RongQing Reviewed-by: Wang Li Reviewed-by: Michal Kubecek Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/ethtool.c | 46 ++++++++++++++++++++++++++++++---------------- 1 file changed, 30 insertions(+), 16 deletions(-) diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 158264f7cfaf..3a7f19a61768 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -1794,11 +1794,16 @@ static int ethtool_get_strings(struct net_device *dev, void __user *useraddr) WARN_ON_ONCE(!ret); gstrings.len = ret; - data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN)); - if (gstrings.len && !data) - return -ENOMEM; - __ethtool_get_strings(dev, gstrings.string_set, data); + if (gstrings.len) { + data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN)); + if (!data) + return -ENOMEM; + + __ethtool_get_strings(dev, gstrings.string_set, data); + } else { + data = NULL; + } ret = -EFAULT; if (copy_to_user(useraddr, &gstrings, sizeof(gstrings))) @@ -1894,11 +1899,15 @@ static int ethtool_get_stats(struct net_device *dev, void __user *useraddr) return -EFAULT; stats.n_stats = n_stats; - data = vzalloc(array_size(n_stats, sizeof(u64))); - if (n_stats && !data) - return -ENOMEM; - ops->get_ethtool_stats(dev, &stats, data); + if (n_stats) { + data = vzalloc(array_size(n_stats, sizeof(u64))); + if (!data) + return -ENOMEM; + ops->get_ethtool_stats(dev, &stats, data); + } else { + data = NULL; + } ret = -EFAULT; if (copy_to_user(useraddr, &stats, sizeof(stats))) @@ -1938,16 +1947,21 @@ static int ethtool_get_phy_stats(struct net_device *dev, void __user *useraddr) return -EFAULT; stats.n_stats = n_stats; - data = vzalloc(array_size(n_stats, sizeof(u64))); - if (n_stats && !data) - return -ENOMEM; - if (dev->phydev && !ops->get_ethtool_phy_stats) { - ret = phy_ethtool_get_stats(dev->phydev, &stats, data); - if (ret < 0) - return ret; + if (n_stats) { + data = vzalloc(array_size(n_stats, sizeof(u64))); + if (!data) + return -ENOMEM; + + if (dev->phydev && !ops->get_ethtool_phy_stats) { + ret = phy_ethtool_get_stats(dev->phydev, &stats, data); + if (ret < 0) + goto out; + } else { + ops->get_ethtool_phy_stats(dev, &stats, data); + } } else { - ops->get_ethtool_phy_stats(dev, &stats, data); + data = NULL; } ret = -EFAULT; -- 2.19.1