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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA451C3DA7A for ; Thu, 5 Jan 2023 22:14:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4E1C5900005; Thu, 5 Jan 2023 17:14:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 491BF8E0001; Thu, 5 Jan 2023 17:14:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3805E900005; Thu, 5 Jan 2023 17:14:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 275708E0001 for ; Thu, 5 Jan 2023 17:14:06 -0500 (EST) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id D63671C6530 for ; Thu, 5 Jan 2023 22:14:05 +0000 (UTC) X-FDA: 80322149250.13.D2A2615 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf27.hostedemail.com (Postfix) with ESMTP id 345C74000D for ; Thu, 5 Jan 2023 22:14:03 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=tlelhkEs; spf=pass (imf27.hostedemail.com: domain of gustavoars@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=gustavoars@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1672956844; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=g7ARxzRg4qeZnxsuTwCkOlUDNOTEW0lHQtXXNhpQJUw=; b=Ft5LUVTgs0cTJ5uwaM45hC9IhVEqEh2rGNqck5xELsWN2aiAZ8SjupOTDp0nmI2mCTiX3F JdDcZyWUEnmJiD3a4PhxrMg+g3y/cCkzX9olF37dYAPMtPpsOxb7q17d8gmJiv7axdC5ow M3QtdVQYlmPW8aNuVU4hW/CfZZHzimE= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=tlelhkEs; spf=pass (imf27.hostedemail.com: domain of gustavoars@kernel.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=gustavoars@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1672956844; a=rsa-sha256; cv=none; b=6cZFbsD3vxhnSO910mg0ZZQl60uqanDxpdqhDce2qDPodN/B6N8jGI/Toq6BTsBHJbrfjr mbjk7x82JaV3VeKCZcBzi88DwyG/aNJZGP2ySPf55+XTb6sQ2WXNwFqij3mYBc3DCUfdkA h+t8ZgHGOxCZFLxBCmPhSYmIkT+tfAo= 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 ams.source.kernel.org (Postfix) with ESMTPS id 18408B81B07; Thu, 5 Jan 2023 22:14:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 46326C433D2; Thu, 5 Jan 2023 22:13:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672956840; bh=Z4eOuR/y0KdIFBiLFGkqOAfGHfUV0LGrmKrUyXhuSV4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tlelhkEsD3B8WqyKGrMXIm8RCLl1yfMt2vGBhC6/cVb4OMXRRtrjPJAhXhcxi2ISf oN+R7lcR+jEJnjCg31rTpKG8cDWlunogBxAVOiIF9fVnKL+bJPmUq3Z5V/aYErMbRS 8T+4kYUm94xf2UDnHZIQ7ZLN0OGh0iiiunTjyiWnvdV962DxZZUgdechk0jMNcf4AH OoSpoYtRYoN5l7QFYlw8htQGW9WGgMaUQck1X13q8RmnZw+t7x2PJ6+qOWHsyEPloF FAzPsZrkStxLEWFdk7EB0OHqSlihf/yROoiqlw2wYo4f8t/j4DavEIhiSgTDCLz9h2 bm2smTqzvhP8g== Date: Thu, 5 Jan 2023 16:14:05 -0600 From: "Gustavo A. R. Silva" To: Kees Cook Cc: Andrew Morton , Dan Williams , Alex Sierra , Felix Kuehling , "Matthew Wilcox (Oracle)" , Shiyang Ruan , linux-mm@kvack.org, Alistair Popple , Joao Martins , Mike Rapoport , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] memremap: Replace 0-length array with flexible array Message-ID: References: <20230105220151.never.343-kees@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230105220151.never.343-kees@kernel.org> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 345C74000D X-Stat-Signature: bz8c6axjziajq4nf8c5gb1utirigus6z X-HE-Tag: 1672956843-713201 X-HE-Meta: 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: I think this is the same patch: https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/ It's actually in linux-next. -- Gustavo On Thu, Jan 05, 2023 at 02:01:53PM -0800, Kees Cook wrote: > Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's > "rule_locs" 0-length array with a flexible array. Detected with GCC 13, > using -fstrict-flex-arrays=3: > > In file included from include/asm-generic/memory_model.h:5, > from arch/x86/include/asm/page.h:86, > from arch/x86/include/asm/thread_info.h:12, > from include/linux/thread_info.h:60, > from arch/x86/include/asm/preempt.h:9, > from include/linux/preempt.h:78, > from include/linux/spinlock.h:56, > from include/linux/mmzone.h:8, > from include/linux/gfp.h:7, > from include/linux/mm.h:7, > from mm/sparse-vmemmap.c:21: > In function 'reuse_compound_section', > inlined from 'vmemmap_populate_compound_pages' at mm/sparse-vmemmap.c:407:6, > inlined from '__populate_section_memmap' at mm/sparse-vmemmap.c:463:7: > mm/sparse-vmemmap.c:376:39: warning: array subscript is outside array bounds of 'struct range[0]' [-Warray-bounds=] > 376 | PHYS_PFN(pgmap->ranges[pgmap->nr_range].start); > | ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~ > include/linux/pfn.h:22:43: note: in definition of macro 'PHYS_PFN' > 22 | #define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT)) > | ^ > In file included from include/linux/mm.h:31: > include/linux/memremap.h: In function '__populate_section_memmap': > include/linux/memremap.h:138:30: note: while referencing 'ranges' > 138 | struct range ranges[0]; > | ^~~~~~ > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays > > Cc: Andrew Morton > Cc: Dan Williams > Cc: Alex Sierra > Cc: Felix Kuehling > Cc: "Matthew Wilcox (Oracle)" > Cc: Shiyang Ruan > Cc: "Gustavo A. R. Silva" > Cc: linux-mm@kvack.org > Signed-off-by: Kees Cook > --- > include/linux/memremap.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/memremap.h b/include/linux/memremap.h > index 7fcaf3180a5b..1314d9c5f05b 100644 > --- a/include/linux/memremap.h > +++ b/include/linux/memremap.h > @@ -135,7 +135,7 @@ struct dev_pagemap { > int nr_range; > union { > struct range range; > - struct range ranges[0]; > + DECLARE_FLEX_ARRAY(struct range, ranges); > }; > }; > > -- > 2.34.1 >