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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 73CEAECE58C for ; Wed, 9 Oct 2019 19:12:58 +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 4C095218DE for ; Wed, 9 Oct 2019 19:12:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4C095218DE 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]:54738 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iIHOK-0005S0-EO for qemu-devel@archiver.kernel.org; Wed, 09 Oct 2019 15:12:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41773) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iIDzG-0001Ae-U2 for qemu-devel@nongnu.org; Wed, 09 Oct 2019 11:34:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iIDzF-0005qh-Qb for qemu-devel@nongnu.org; Wed, 09 Oct 2019 11:34:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47058) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iIDzD-0005ma-De; Wed, 09 Oct 2019 11:34:47 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 4888B806A7A; Wed, 9 Oct 2019 15:34:46 +0000 (UTC) Received: from [10.3.116.162] (ovpn-116-162.phx2.redhat.com [10.3.116.162]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E63E35DA2C; Wed, 9 Oct 2019 15:34:41 +0000 (UTC) Subject: Re: [PATCH 01/10] hbitmap: introduce HBITMAP_MAX_ORIG_SIZE To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20190930151502.7829-1-vsementsov@virtuozzo.com> <20190930151502.7829-2-vsementsov@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: Date: Wed, 9 Oct 2019 10:34:41 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.0 MIME-Version: 1.0 In-Reply-To: <20190930151502.7829-2-vsementsov@virtuozzo.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.67]); Wed, 09 Oct 2019 15:34:46 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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: kwolf@redhat.com, fam@euphon.net, qemu-devel@nongnu.org, mreitz@redhat.com, den@openvz.org, jsnow@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 9/30/19 10:14 AM, Vladimir Sementsov-Ogievskiy wrote: > Signed-off-by: Vladimir Sementsov-Ogievskiy A bit light on the commit message for explaining why. > --- > include/qemu/hbitmap.h | 7 +++++++ > util/hbitmap.c | 2 ++ > 2 files changed, 9 insertions(+) > > diff --git a/include/qemu/hbitmap.h b/include/qemu/hbitmap.h > index 1bf944ca3d..82317c5364 100644 > --- a/include/qemu/hbitmap.h > +++ b/include/qemu/hbitmap.h > @@ -33,6 +33,13 @@ typedef struct HBitmapIter HBitmapIter; > */ > #define HBITMAP_LEVELS ((HBITMAP_LOG_MAX_SIZE / BITS_PER_LEVEL) + 1) > > +/* > + * We have APIs which returns signed int64_t, to be able to return error. > + * Therefore we can't handle bitmaps with absolute size larger than > + * (INT64_MAX+1). Still, keep it INT64_MAX to be a bit safer. > + */ > +#define HBITMAP_MAX_ORIG_SIZE INT64_MAX That, and bitmaps represent disk images, but disk images can't exceed INT64_MAX bytes (thanks to off_t being signed). But does introducing a new constant really help? > + > struct HBitmapIter { > const HBitmap *hb; > > diff --git a/util/hbitmap.c b/util/hbitmap.c > index 757d39e360..df192234e3 100644 > --- a/util/hbitmap.c > +++ b/util/hbitmap.c > @@ -708,6 +708,7 @@ HBitmap *hbitmap_alloc(uint64_t size, int granularity) > HBitmap *hb = g_new0(struct HBitmap, 1); > unsigned i; > > + assert(size <= HBITMAP_MAX_ORIG_SIZE); or can we just inline INT64_MAX here? > hb->orig_size = size; > > assert(granularity >= 0 && granularity < 64); > @@ -738,6 +739,7 @@ void hbitmap_truncate(HBitmap *hb, uint64_t size) > uint64_t num_elements = size; > uint64_t old; > > + assert(size <= HBITMAP_MAX_ORIG_SIZE); > hb->orig_size = size; > > /* Size comes in as logical elements, adjust for granularity. */ > -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org