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 99C1DE784AB for ; Mon, 2 Oct 2023 16:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238342AbjJBQvQ (ORCPT ); Mon, 2 Oct 2023 12:51:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237797AbjJBQvO (ORCPT ); Mon, 2 Oct 2023 12:51:14 -0400 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::226]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E64FBD; Mon, 2 Oct 2023 09:51:09 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPSA id 4C3C2C000D; Mon, 2 Oct 2023 16:51:03 +0000 (UTC) Message-ID: <689fe81f-e2b4-9f99-4005-8ae330afb869@ovn.org> Date: Mon, 2 Oct 2023 18:51:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Cc: dev@openvswitch.org, netdev@vger.kernel.org, llvm@lists.linux.dev, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, i.maximets@ovn.org Subject: Re: [ovs-dev] [PATCH net-next 2/2] net: openvswitch: Annotate struct mask_array with __counted_byUse struct_size() Content-Language: en-US To: Christophe JAILLET , keescook@chromium.org, Pravin B Shelar , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Gustavo A. R. Silva" , Nathan Chancellor , Nick Desaulniers , Tom Rix References: <8be59c9e06fca8eff2f264abb4c2f74db0b19a9e.1696156198.git.christophe.jaillet@wanadoo.fr> From: Ilya Maximets In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-GND-Sasl: i.maximets@ovn.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/1/23 13:07, Christophe JAILLET wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > Signed-off-by: Christophe JAILLET > --- > This patch is part of a work done in parallel of what is currently worked > on by Kees Cook. > > My patches are only related to corner cases that do NOT match the > semantic of his Coccinelle script[1]. > > In this case, in tbl_mask_array_alloc(), several things are allocated with > a single allocation. Then, some pointer arithmetic computes the address of > the memory after the flex-array. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > --- > net/openvswitch/flow_table.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/openvswitch/flow_table.h b/net/openvswitch/flow_table.h > index 9e659db78c05..8d9e83b4d62c 100644 > --- a/net/openvswitch/flow_table.h > +++ b/net/openvswitch/flow_table.h > @@ -48,7 +48,7 @@ struct mask_array { > int count, max; > struct mask_array_stats __percpu *masks_usage_stats; > u64 *masks_usage_zero_cntr; > - struct sw_flow_mask __rcu *masks[]; > + struct sw_flow_mask __rcu *masks[] __counted_by(size); Did you mean 'max'? There is no 'size' in the structure. Also, the patch subject is messed up a bit. Best regards, Ilya Maximets.