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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 E329EC433DF for ; Mon, 18 May 2020 17:41:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE5062083E for ; Mon, 18 May 2020 17:41:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823690; bh=JqRgiC5oYKqAVpV4yT7oxR7d3y6q8ssrO6NFSNzpyT4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IuvZhRKlFKbxTxUZa/BTu8mBnq6J051fYPkX6DSd/cey01UtyuAAKlII0TpHj07yB 5oTHgzdaNODw4y4n/5W5QLPa9Onv7JqUcdIT2rkOcGjof40dR0zXPebfTw3RBbfl5h TUm+B3hWVfdAn8TW2rE7gCAPyvyUXM92rgGBlX/A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728671AbgERRla (ORCPT ); Mon, 18 May 2020 13:41:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:37650 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728622AbgERRlY (ORCPT ); Mon, 18 May 2020 13:41:24 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CBAEC207C4; Mon, 18 May 2020 17:41:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823682; bh=JqRgiC5oYKqAVpV4yT7oxR7d3y6q8ssrO6NFSNzpyT4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Pf8Nx2EIjoTYIsQW0reBYxgCgs/4peMnXWlSJLyfQ1wGmRe++V8Gr19elSqq5d6Ag L5t2S+GOXj3krCWAF78HgAONLjaB9ojWsono2537lPAQGwenLqA+A2IuJ3RWMkivGS f2ljdXZI4dv45BawbHy6HgJUL119QdTAREfyCzXQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.4 53/86] netfilter: conntrack: avoid gcc-10 zero-length-bounds warning Date: Mon, 18 May 2020 19:36:24 +0200 Message-Id: <20200518173501.293333661@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173450.254571947@linuxfoundation.org> References: <20200518173450.254571947@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann [ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ] gcc-10 warns around a suspicious access to an empty struct member: net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc': net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds] 1522 | memset(&ct->__nfct_init_offset[0], 0, | ^~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from net/netfilter/nf_conntrack_core.c:37: include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset' 90 | u8 __nfct_init_offset[0]; | ^~~~~~~~~~~~~~~~~~ The code is correct but a bit unusual. Rework it slightly in a way that does not trigger the warning, using an empty struct instead of an empty array. There are probably more elegant ways to do this, but this is the smallest change. Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer") Signed-off-by: Arnd Bergmann Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- include/net/netfilter/nf_conntrack.h | 2 +- net/netfilter/nf_conntrack_core.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index 636e9e11bd5f6..e3f73fd1d53a9 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -98,7 +98,7 @@ struct nf_conn { possible_net_t ct_net; /* all members below initialized via memset */ - u8 __nfct_init_offset[0]; + struct { } __nfct_init_offset; /* If we were expected by an expectation, this will be it */ struct nf_conn *master; diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index de0aad12b91d2..e58516274e86a 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -898,9 +898,9 @@ __nf_conntrack_alloc(struct net *net, /* Don't set timer yet: wait for confirmation */ setup_timer(&ct->timeout, death_by_timeout, (unsigned long)ct); write_pnet(&ct->ct_net, net); - memset(&ct->__nfct_init_offset[0], 0, + memset(&ct->__nfct_init_offset, 0, offsetof(struct nf_conn, proto) - - offsetof(struct nf_conn, __nfct_init_offset[0])); + offsetof(struct nf_conn, __nfct_init_offset)); if (zone && nf_ct_zone_add(ct, GFP_ATOMIC, zone) < 0) goto out_free; -- 2.20.1