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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 5C3B3C07E95 for ; Tue, 13 Jul 2021 16:08:23 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id DB40F61164 for ; Tue, 13 Jul 2021 16:08:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB40F61164 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:58606 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m3KxJ-00045v-JQ for qemu-devel@archiver.kernel.org; Tue, 13 Jul 2021 12:08:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34310) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m3KwC-00033g-0N for qemu-devel@nongnu.org; Tue, 13 Jul 2021 12:07:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:49131) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m3Kw8-0006he-Ns for qemu-devel@nongnu.org; Tue, 13 Jul 2021 12:07:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626192426; h=from:from: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=anoAiWxKSZcX7m4NLi2U5E7aMa/BD/RZWalWu03KJG4=; b=PoixUnRkgNi0EJD1WEXICWZYISDjy8HTNQJzJRO3+jzBg/kcNG1P7i/p0l7F0XM8njJu0P RIErYGH3Hv2MHQm/Xv/9yzMPnQzc84RWvV5UvfLq/jXRU0erQmtgBdBCbn6Rc/i7mdPDv6 HHNFjT/lDqmQgEeDKGUOhJK7w9O8Ers= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-470-2M-9v1pAM0We_5btJlFvmw-1; Tue, 13 Jul 2021 12:07:02 -0400 X-MC-Unique: 2M-9v1pAM0We_5btJlFvmw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B02DD804141; Tue, 13 Jul 2021 16:07:01 +0000 (UTC) Received: from redhat.com (ovpn-113-49.phx2.redhat.com [10.3.113.49]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4B5FA5D9CA; Tue, 13 Jul 2021 16:07:01 +0000 (UTC) Date: Tue, 13 Jul 2021 11:06:59 -0500 From: Eric Blake To: Richard Henderson Subject: Re: [PATCH 03/11] util/selfmap: Discard mapping on error Message-ID: <20210713160659.kxrjl6nnswoguncv@redhat.com> References: <20210712215535.1471256-1-richard.henderson@linaro.org> <20210712215535.1471256-4-richard.henderson@linaro.org> MIME-Version: 1.0 In-Reply-To: <20210712215535.1471256-4-richard.henderson@linaro.org> User-Agent: NeoMutt/20210205-569-37ed14 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.7, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alex =?utf-8?Q?Benn=C3=A9e?= , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Jul 12, 2021 at 02:55:27PM -0700, Richard Henderson wrote: > From clang-13: > util/selfmap.c:26:21: error: variable 'errors' set but not used \ > [-Werror,-Wunused-but-set-variable] > > Quite right of course, but there's no reason not to check errors. > > First, incrementing errors is incorrect, because qemu_strtoul > returns an errno not a count -- just or them together so that > we have a non-zero value at the end. > > Second, if we have an error, do not add the struct to the list, > but free it instead. > > Cc: Alex Bennée > Signed-off-by: Richard Henderson > --- > util/selfmap.c | 28 ++++++++++++++++------------ > 1 file changed, 16 insertions(+), 12 deletions(-) > > diff --git a/util/selfmap.c b/util/selfmap.c > index 2ec99dfdda..0178c2ff8b 100644 > --- a/util/selfmap.c > +++ b/util/selfmap.c > @@ -23,29 +23,33 @@ GSList *read_self_maps(void) > gchar **fields = g_strsplit(lines[i], " ", 6); > if (g_strv_length(fields) > 4) { > MapInfo *e = g_new0(MapInfo, 1); > - int errors; > + int errors = 0; > const char *end; > > - errors = qemu_strtoul(fields[0], &end, 16, &e->start); > - errors += qemu_strtoul(end + 1, NULL, 16, &e->end); > + errors |= qemu_strtoul(fields[0], &end, 16, &e->start); > + errors |= qemu_strtoul(end + 1, NULL, 16, &e->end); > > e->is_read = fields[1][0] == 'r'; > e->is_write = fields[1][1] == 'w'; > e->is_exec = fields[1][2] == 'x'; > e->is_priv = fields[1][3] == 'p'; > > - errors += qemu_strtoul(fields[2], NULL, 16, &e->offset); > + errors |= qemu_strtoul(fields[2], NULL, 16, &e->offset); > e->dev = g_strdup(fields[3]); e->dev now contains malloc'd memory... > - errors += qemu_strtou64(fields[4], NULL, 10, &e->inode); > + errors |= qemu_strtou64(fields[4], NULL, 10, &e->inode); ...and if this qemu_strtou64 fails... > > - /* > - * The last field may have leading spaces which we > - * need to strip. > - */ > - if (g_strv_length(fields) == 6) { > - e->path = g_strdup(g_strchug(fields[5])); > + if (!errors) { > + /* > + * The last field may have leading spaces which we > + * need to strip. > + */ > + if (g_strv_length(fields) == 6) { > + e->path = g_strdup(g_strchug(fields[5])); > + } > + map_info = g_slist_prepend(map_info, e); > + } else { > + g_free(e); ...you've now leaked it. Oops. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org