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=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 0D096C48BE5 for ; Thu, 17 Jun 2021 07:25:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E40926135C for ; Thu, 17 Jun 2021 07:25:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230118AbhFQH1J (ORCPT ); Thu, 17 Jun 2021 03:27:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:51196 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229683AbhFQH1I (ORCPT ); Thu, 17 Jun 2021 03:27:08 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 105A26135C; Thu, 17 Jun 2021 07:25:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623914701; bh=Sbblh3hwD2BaQ81tKBnnpgdkyDBrz2PvnAvQk8AMWOQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=l3g3Bluo1oqyuRFLWlXlY+tODWOWwaJ7jImdeom9lhnH9mt8qCNBbmiBvr80gJF5v QYY543gKEU4+23C8LpRKqnpRrV6+zzEtyB41DjZ8LxEuasAjzMpDU4gcXWPtUpLYsq rQ3UBVgY6p2EMQcqkoKb3vfbJlMlzSOQg8+5Kj4sWSd8suQTfaT1esUoCh/X8Qcc8k QpYtFi+xef8VbqTGGD9/gkz+PSI0RT+jA61Xs44wu8nj2Rd+vNL46iKFDgvfzKDigJ yL9QsmDPZvP23TvSTb2FQ+/jom+oaEWteFYHlPFTrZs1Xn7VSBkm+aF75jd1+B/DMW l7ocP0qTSa22A== Date: Thu, 17 Jun 2021 10:24:58 +0300 From: Leon Romanovsky To: Kees Cook , Jack Morgenstein Cc: Jason Gunthorpe , Yishai Hadas , Doug Ledford , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] IB/mlx4: Avoid field-overflowing memcpy() Message-ID: References: <20210616203744.1248551-1-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210616203744.1248551-1-keescook@chromium.org> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Wed, Jun 16, 2021 at 01:37:44PM -0700, Kees Cook wrote: > In preparation for FORTIFY_SOURCE performing compile-time and run-time > field bounds checking for memcpy(), memmove(), and memset(), avoid > intentionally writing across neighboring array fields. > > Use the ether_addr_copy() helper instead, as already done for smac. > > Signed-off-by: Kees Cook > --- > drivers/infiniband/hw/mlx4/qp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c > index 2ae22bf50016..4a2ef7daaded 100644 > --- a/drivers/infiniband/hw/mlx4/qp.c > +++ b/drivers/infiniband/hw/mlx4/qp.c > @@ -3144,7 +3144,7 @@ static int build_mlx_header(struct mlx4_ib_qp *qp, const struct ib_ud_wr *wr, > mlx->sched_prio = cpu_to_be16(pcp); > > ether_addr_copy(sqp->ud_header.eth.smac_h, ah->av.eth.s_mac); > - memcpy(sqp->ud_header.eth.dmac_h, ah->av.eth.mac, 6); > + ether_addr_copy(sqp->ud_header.eth.dmac_h, ah->av.eth.mac); > memcpy(&ctrl->srcrb_flags16[0], ah->av.eth.mac, 2); > memcpy(&ctrl->imm, ah->av.eth.mac + 2, 4); I don't understand the last three lines. We are copying 6 bytes to ah->av.eth.mac and immediately after that overwriting them. Jack, Do you remember what you wanted to achieve in commit 6ee51a4e866b ("mlx4: Adjust QP1 multiplexing for RoCE/SRIOV") Thanks > > -- > 2.25.1 >