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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 5A6BAC4727F for ; Mon, 28 Sep 2020 07:43:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C42322207 for ; Mon, 28 Sep 2020 07:43:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601278989; bh=qEiBrfNJfo3j3guhrzPxyPtqthA1XxTL+21RNCztAmk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=eH+YtVSrBqv+Vty2hdPWyMv1MT2wq9S9w2voBlu7xqSyed9K1krzCGnUIzwdSC+Et fQulx2OTd2YLCrDI0JlZYmfvsPac5++Az6aQUd1cvz9CyIdHwT1jRnpCls16xJV7zN pW7ybnX+PZnISY3DBdFgF9mW3dq28hiay6PS5x0E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726613AbgI1HnG (ORCPT ); Mon, 28 Sep 2020 03:43:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:51906 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726440AbgI1HnF (ORCPT ); Mon, 28 Sep 2020 03:43:05 -0400 Received: from localhost (unknown [213.57.247.131]) (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 600122100A; Mon, 28 Sep 2020 07:43:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601278985; bh=qEiBrfNJfo3j3guhrzPxyPtqthA1XxTL+21RNCztAmk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=eB2WTXQVs4jt4p9BSTF7D/b7ouPEOUWfddSU8u9DKfDzceoLwj81z9U77eLd+X96S QssGSS5VdGJGgGOaB2W2Bc8px9X1Cgroo8joTvvbQH+U03Bg0zax82FKLZPi+skVsr /k6kVfCQonSpYR7G1YwSYjhoMC71ruWXWRkDy1m0= Date: Mon, 28 Sep 2020 10:43:01 +0300 From: Leon Romanovsky To: Alex Dewar Cc: Saeed Mahameed , "David S. Miller" , Jakub Kicinski , Roi Dayan , Oz Shlomo , Paul Blakey , Ariel Levkovich , Eli Britstein , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] net/mlx5e: Fix use of freed pointer Message-ID: <20200928074301.GC3094@unreal> References: <20200927113254.362480-1-alex.dewar90@gmail.com> <20200927113254.362480-3-alex.dewar90@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200927113254.362480-3-alex.dewar90@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Sep 27, 2020 at 12:32:53PM +0100, Alex Dewar wrote: > If the call to mlx5_fc_create() fails, then shared_counter will be freed > before its member, shared_counter->counter, is accessed to retrieve the > error code. Fix by using an intermediate variable. > > Addresses-Coverity: CID 1497153: Memory - illegal accesses (USE_AFTER_FREE) > Signed-off-by: Alex Dewar > --- Please add Fixes line. > drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c > index b5f8ed30047b..5851a1dfe6e4 100644 > --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c > +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c > @@ -738,6 +738,7 @@ mlx5_tc_ct_shared_counter_get(struct mlx5_tc_ct_priv *ct_priv, > struct mlx5_ct_shared_counter *shared_counter; > struct mlx5_core_dev *dev = ct_priv->dev; > struct mlx5_ct_entry *rev_entry; > + struct mlx5_fc *counter; > __be16 tmp_port; > > /* get the reversed tuple */ > @@ -775,12 +776,13 @@ mlx5_tc_ct_shared_counter_get(struct mlx5_tc_ct_priv *ct_priv, > if (!shared_counter) > return ERR_PTR(-ENOMEM); > > - shared_counter->counter = mlx5_fc_create(dev, true); > - if (IS_ERR(shared_counter->counter)) { > + counter = mlx5_fc_create(dev, true); > + if (IS_ERR(counter)) { > ct_dbg("Failed to create counter for ct entry"); > kfree(shared_counter); > - return ERR_PTR(PTR_ERR(shared_counter->counter)); > + return (struct mlx5_ct_shared_counter *)counter; return ERR_CAST(counter); > } > + shared_counter->counter = counter; > > refcount_set(&shared_counter->refcount, 1); > return shared_counter; > -- > 2.28.0 >