From patchwork Mon Oct 28 12:14:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 11215263 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E246413BD for ; Mon, 28 Oct 2019 12:26:33 +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 B7C5720717 for ; Mon, 28 Oct 2019 12:26:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Py3Jr1yc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B7C5720717 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:53178 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iP46S-00083q-Lq for patchwork-qemu-devel@patchwork.kernel.org; Mon, 28 Oct 2019 08:26:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:49892) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iP3vj-0001KY-Cb for qemu-devel@nongnu.org; Mon, 28 Oct 2019 08:15:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iP3vh-0001Ha-Sv for qemu-devel@nongnu.org; Mon, 28 Oct 2019 08:15:27 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:32941 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iP3vh-0001HD-Px for qemu-devel@nongnu.org; Mon, 28 Oct 2019 08:15:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1572264925; 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=+u3lp8jOpNBLwLVCT1zHP7gb5DU6N9uK+QT6kLBH7ew=; b=Py3Jr1yc3iFmNlOVE7w9HvLLPqIyImwKi1OMXksOA69zAnH1hSpMZnQZjn5fSd2tinG825 byAkoDeWj6wHvjC7vGi0AGEF9dZ773yEQjlcT+F54wb1qgJ9d43tLnPGaCXp4v8W+f1fKr Sjkqf+BBHUMhP37GQW3Kj48WoB90/Ck= 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-65-calFd69FMcKkOYYSNPTMAQ-1; Mon, 28 Oct 2019 08:15:21 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 802B5800FF1; Mon, 28 Oct 2019 12:15:20 +0000 (UTC) Received: from localhost (ovpn-117-83.ams2.redhat.com [10.36.117.83]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1EFF4600C7; Mon, 28 Oct 2019 12:15:19 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PULL 08/69] hbitmap: handle set/reset with zero length Date: Mon, 28 Oct 2019 13:14:00 +0100 Message-Id: <20191028121501.15279-9-mreitz@redhat.com> In-Reply-To: <20191028121501.15279-1-mreitz@redhat.com> References: <20191028121501.15279-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: calFd69FMcKkOYYSNPTMAQ-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: Kevin Wolf , Peter Maydell , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vladimir Sementsov-Ogievskiy Passing zero length to these functions leads to unpredicted results. Zero-length set/reset may occur in active-mirror, on zero-length write (which is unlikely, but not guaranteed to never happen). Let's just do nothing on zero-length request. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-id: 20191011090711.19940-2-vsementsov@virtuozzo.com Reviewed-by: Max Reitz Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz --- util/hbitmap.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/util/hbitmap.c b/util/hbitmap.c index 66db87c6ff..242c6e519c 100644 --- a/util/hbitmap.c +++ b/util/hbitmap.c @@ -387,6 +387,10 @@ void hbitmap_set(HBitmap *hb, uint64_t start, uint64_t count) uint64_t first, n; uint64_t last = start + count - 1; + if (count == 0) { + return; + } + trace_hbitmap_set(hb, start, count, start >> hb->granularity, last >> hb->granularity); @@ -478,6 +482,10 @@ void hbitmap_reset(HBitmap *hb, uint64_t start, uint64_t count) uint64_t last = start + count - 1; uint64_t gran = 1ULL << hb->granularity; + if (count == 0) { + return; + } + assert(QEMU_IS_ALIGNED(start, gran)); assert(QEMU_IS_ALIGNED(count, gran) || (start + count == hb->orig_size));