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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 727B2C77B73 for ; Mon, 22 May 2023 12:45:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q14ut-0006mF-B0; Mon, 22 May 2023 08:45:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q14uD-0006h3-RT for qemu-devel@nongnu.org; Mon, 22 May 2023 08:44:57 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q14u4-0001NF-Tg for qemu-devel@nongnu.org; Mon, 22 May 2023 08:44:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684759477; h=from:from:reply-to: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bR6j1xkWB8o4B8a2NjzYw0/QOvC4ezqNvjmSQaNVsjA=; b=AGlNcwjR6CnfITFRY8VlNIvMsQ1vTdyfYvzbep849xsQfs9jM2+Ww8KS4uGbRO8BXDz2NM zZWueCtk8h81e03UDj3X502RKiBEPlAUlZ2CHNDEs8HZqflB/34OvsftMcPFhllf1E2N+U tiuMhpdv6mR8WtDD/VbCLlZtB8KYr6k= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-518-A4XkPaBGOCmh7GvjuB_lDA-1; Mon, 22 May 2023 08:44:35 -0400 X-MC-Unique: A4XkPaBGOCmh7GvjuB_lDA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 605843825BA6; Mon, 22 May 2023 12:44:35 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.122]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4AEC67B7C; Mon, 22 May 2023 12:44:33 +0000 (UTC) Date: Mon, 22 May 2023 13:44:29 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= Cc: Akihiko Odaki , qemu-devel@nongnu.org, Alex Williamson , =?utf-8?Q?C=C3=A9dric?= Le Goater Subject: Re: [PATCH] util/vfio-helpers: Use g_file_read_link() Message-ID: References: <20230522114943.33024-1-akihiko.odaki@daynix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, May 22, 2023 at 02:38:44PM +0200, Philippe Mathieu-Daudé wrote: > On 22/5/23 13:49, Akihiko Odaki wrote: > > When _FORTIFY_SOURCE=2, glibc version is 2.35, and GCC version is > > 12.1.0, the compiler complains as follows: > > > > In file included from /usr/include/features.h:490, > > from /usr/include/bits/libc-header-start.h:33, > > from /usr/include/stdint.h:26, > > from /usr/lib/gcc/aarch64-unknown-linux-gnu/12.1.0/include/stdint.h:9, > > from /home/alarm/q/var/qemu/include/qemu/osdep.h:94, > > from ../util/vfio-helpers.c:13: > > In function 'readlink', > > inlined from 'sysfs_find_group_file' at ../util/vfio-helpers.c:116:9, > > inlined from 'qemu_vfio_init_pci' at ../util/vfio-helpers.c:326:18, > > inlined from 'qemu_vfio_open_pci' at ../util/vfio-helpers.c:517:9: > > /usr/include/bits/unistd.h:119:10: error: argument 2 is null but the corresponding size argument 3 value is 4095 [-Werror=nonnull] > > 119 | return __glibc_fortify (readlink, __len, sizeof (char), > > | ^~~~~~~~~~~~~~~ > > > > This error implies the allocated buffer can be NULL. Use > > g_file_read_link(), which allocates buffer automatically to avoid the > > error. > > > > Signed-off-by: Akihiko Odaki > > --- > > util/vfio-helpers.c | 8 +++++--- > > 1 file changed, 5 insertions(+), 3 deletions(-) > > > > diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c > > index 2d8af38f88..e482ab22e2 100644 > > --- a/util/vfio-helpers.c > > +++ b/util/vfio-helpers.c > > @@ -106,15 +106,17 @@ struct QEMUVFIOState { > > */ > > static char *sysfs_find_group_file(const char *device, Error **errp) > > { > > + g_autoptr(GError) gerr; > > Shouldn't this also be NULL-initialized (other picky compilers)? Yes, *all* use of g_auto* must have an initializer at time of declaration. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|