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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63E54C433EF for ; Sun, 21 Nov 2021 13:55:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238248AbhKUN6E (ORCPT ); Sun, 21 Nov 2021 08:58:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:44494 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234993AbhKUN6E (ORCPT ); Sun, 21 Nov 2021 08:58:04 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B5C7D603E8; Sun, 21 Nov 2021 13:54:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637502899; bh=RcfZsnPLw3rO0pzRMpMxv5KHNSIfG8d0yKgbcOFOweY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Pbf1oXEoNHcmssqp70xEBLJOTJXQBnEKAx8gL70kRgC0wfOPdhXXWH4ZurF/vNM/5 6TgMA5jx/YAtwkFZkg3RHYbaEEBN2T5z3AfqS1LQGH9DEjPgX0VrJx4lzG6QQsq+/N FzS0/m2C2Z4W2WiW9cY7hnxbAu8aDzm3rIvO++zTpA4sW3OMj31dud1tpZBboGzYSL aKiPcZdwmGdepd4gVCQ6ZSLevrTn3F/Nrlh1kAMmQDJHOP8CQEj/UBLGgAXZCsjs76 YMu0uqUfEq5xjM7pt4lXur0Y9R8qljO9KMDYOOzB8hXTY9NplL5mAgTDRmR4+k+vdP +w9DbtLq2ZBlA== Date: Sun, 21 Nov 2021 15:54:55 +0200 From: Leon Romanovsky To: Kees Cook Cc: Doug Ledford , Jason Gunthorpe , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] RDMA/mlx5: Use memset_after() to zero struct mlx5_ib_mr Message-ID: References: <20211118203138.1287134-1-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211118203138.1287134-1-keescook@chromium.org> Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Thu, Nov 18, 2021 at 12:31:38PM -0800, Kees Cook wrote: > In preparation for FORTIFY_SOURCE performing compile-time and run-time > field bounds checking for memset(), avoid intentionally writing across > neighboring fields. > > Use memset_after() to zero the end of struct mlx5_ib_mr that should > be initialized. > > Signed-off-by: Kees Cook > --- > drivers/infiniband/hw/mlx5/mlx5_ib.h | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h > index e636e954f6bf..af94c9fe8753 100644 > --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h > +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h > @@ -665,8 +665,7 @@ struct mlx5_ib_mr { > /* User MR data */ > struct mlx5_cache_ent *cache_ent; > struct ib_umem *umem; > - > - /* This is zero'd when the MR is allocated */ > + /* Everything after umem is zero'd when the MR is allocated */ > union { > /* Used only while the MR is in the cache */ > struct { > @@ -718,7 +717,7 @@ struct mlx5_ib_mr { > /* Zero the fields in the mr that are variant depending on usage */ > static inline void mlx5_clear_mr(struct mlx5_ib_mr *mr) > { > - memset(mr->out, 0, sizeof(*mr) - offsetof(struct mlx5_ib_mr, out)); > + memset_after(mr, 0, umem); I think that it is not equivalent change and you need "memset_after(mr, 0, cache_ent);" to clear umem pointer too. > } > > static inline bool is_odp_mr(struct mlx5_ib_mr *mr) > -- > 2.30.2 >