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 41F9AC4332F for ; Fri, 18 Nov 2022 04:29:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240833AbiKRE3y (ORCPT ); Thu, 17 Nov 2022 23:29:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235016AbiKRE3x (ORCPT ); Thu, 17 Nov 2022 23:29:53 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B99A1ADAE; Thu, 17 Nov 2022 20:29:52 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 81FE962308; Fri, 18 Nov 2022 04:29:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3E46C433C1; Fri, 18 Nov 2022 04:29:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1668745790; bh=mOMFpTq0wEGsUBY3eHX7t2CuNkWSUb9x9HDIWPh/G68=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MUl75vX/jZrj9JXskHpLcLDqZjQ7XejdiKXXWoLT/OLQRRG18NsuRhhQpGyk+P7Vl sIVJf6Hp48eLdHrDx6OG7MNjISteFtYAzxi0zA+9VigXLqWMaWiVHzX5mlA69ZqmFm n2/SYvmszW9/FTDZm+or5iFKV6SBzBuSLyMtg0ZsYzgsBdXw83UUHUI8bzYFi5wV3A DQmNoIr964Ot6BUGE9/OlyBVwklMBcjnrDGvwFhuE6Vm8AE35md1ta0H1UwNcTL/7P k+jWEOyzKXlfzbAkZ1IGiqXu6sbAUw8vH3NEO3CX9xMpSRdwZ1F2B0v/kTqMcA22NK O4j1OZDTd/8jQ== Date: Thu, 17 Nov 2022 22:29:36 -0600 From: "Gustavo A. R. Silva" To: Kees Cook Cc: Jakub Kicinski , "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Eric Dumazet , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] ipv4/fib: Replace zero-length array with DECLARE_FLEX_ARRAY() helper Message-ID: References: <20221118042142.never.400-kees@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221118042142.never.400-kees@kernel.org> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Nov 17, 2022 at 08:21:52PM -0800, Kees Cook wrote: > Zero-length arrays are deprecated[1] and are being replaced with > flexible array members in support of the ongoing efforts to tighten the > FORTIFY_SOURCE routines on memcpy(), correctly instrument array indexing > with UBSAN_BOUNDS, and to globally enable -fstrict-flex-arrays=3. > > Replace zero-length array with flexible-array member in struct key_vector. > > This results in no differences in binary output. > > [1] https://github.com/KSPP/linux/issues/78 > > Cc: Jakub Kicinski > Cc: "David S. Miller" > Cc: Hideaki YOSHIFUJI > Cc: David Ahern > Cc: Eric Dumazet > Cc: Paolo Abeni > Cc: "Gustavo A. R. Silva" > Cc: netdev@vger.kernel.org > Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Thanks! -- Gustavo > --- > net/ipv4/fib_trie.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c > index 452ff177e4da..c88bf856c443 100644 > --- a/net/ipv4/fib_trie.c > +++ b/net/ipv4/fib_trie.c > @@ -126,7 +126,7 @@ struct key_vector { > /* This list pointer if valid if (pos | bits) == 0 (LEAF) */ > struct hlist_head leaf; > /* This array is valid if (pos | bits) > 0 (TNODE) */ > - struct key_vector __rcu *tnode[0]; > + DECLARE_FLEX_ARRAY(struct key_vector __rcu *, tnode); > }; > }; > > -- > 2.34.1 >