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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 3309DC43381 for ; Mon, 1 Apr 2019 18:05:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EA1420880 for ; Mon, 1 Apr 2019 18:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730669AbfDASFc (ORCPT ); Mon, 1 Apr 2019 14:05:32 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:32950 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729741AbfDARNF (ORCPT ); Mon, 1 Apr 2019 13:13:05 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id D561A14B8AF69; Mon, 1 Apr 2019 10:13:04 -0700 (PDT) Date: Fri, 29 Mar 2019 13:42:40 -0700 (PDT) Message-Id: <20190329.134240.2198417000673971691.davem@davemloft.net> To: lirongqing@baidu.com Cc: netdev@vger.kernel.org, mkubecek@suse.cz Subject: Re: [PATCH][v2] net: ethtool: not call vzalloc for zero sized memory request From: David Miller In-Reply-To: <1553822282-6658-1-git-send-email-lirongqing@baidu.com> References: <1553822282-6658-1-git-send-email-lirongqing@baidu.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 01 Apr 2019 10:13:05 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Li RongQing Date: Fri, 29 Mar 2019 09:18:02 +0800 > 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 > --- > v1->v2: not call get_ethtool_stats if n_stats is 0 Applied and queued up for -stable, thanks.