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=-6.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 B42DDC4727D for ; Sun, 4 Oct 2020 21:48:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 819E8206DD for ; Sun, 4 Oct 2020 21:48:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726583AbgJDVsZ (ORCPT ); Sun, 4 Oct 2020 17:48:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726351AbgJDVsZ (ORCPT ); Sun, 4 Oct 2020 17:48:25 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22A16C0613CE; Sun, 4 Oct 2020 14:48:25 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (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 90DD212780A38; Sun, 4 Oct 2020 14:31:36 -0700 (PDT) Date: Sun, 04 Oct 2020 14:48:23 -0700 (PDT) Message-Id: <20201004.144823.620544782441330271.davem@davemloft.net> To: anant.thazhemadam@gmail.com Cc: linux-kernel-mentees@lists.linuxfoundation.org, syzbot+69b804437cfec30deac3@syzkaller.appspotmail.com, jiri@resnulli.us, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: team: fix memory leak in __team_options_register From: David Miller In-Reply-To: <20201004205536.4734-1-anant.thazhemadam@gmail.com> References: <20201004205536.4734-1-anant.thazhemadam@gmail.com> X-Mailer: Mew version 6.8 on Emacs 27.1 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 [2620:137:e000::1:9]); Sun, 04 Oct 2020 14:31:36 -0700 (PDT) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Anant Thazhemadam Date: Mon, 5 Oct 2020 02:25:36 +0530 > The variable "i" isn't initialized back correctly after the first loop > under the label inst_rollback gets executed. > > The value of "i" is assigned to be option_count - 1, and the ensuing > loop (under alloc_rollback) begins by initializing i--. > Thus, the value of i when the loop begins execution will now become > i = option_count - 2. > > Thus, when kfree(dst_opts[i]) is called in the second loop in this > order, (i.e., inst_rollback followed by alloc_rollback), > dst_optsp[option_count - 2] is the first element freed, and > dst_opts[option_count - 1] does not get freed, and thus, a memory > leak is caused. > > This memory leak can be fixed, by assigning i = option_count (instead of > option_count - 1). > > Fixes: 80f7c6683fe0 ("team: add support for per-port options") > Reported-by: syzbot+69b804437cfec30deac3@syzkaller.appspotmail.com > Tested-by: syzbot+69b804437cfec30deac3@syzkaller.appspotmail.com > Signed-off-by: Anant Thazhemadam Applied and queued up for -stable, thank you.