From patchwork Mon Mar 2 15:09:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Vladimir Sementsov-Ogievskiy X-Patchwork-Id: 11415739 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 3143014B7 for ; Mon, 2 Mar 2020 15:10:31 +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 DF062214DB for ; Mon, 2 Mar 2020 15:10:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF062214DB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.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]:33842 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8miE-0005Wa-4a for patchwork-qemu-devel@patchwork.kernel.org; Mon, 02 Mar 2020 10:10:30 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:37488) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8mhX-0004lc-Jw for qemu-devel@nongnu.org; Mon, 02 Mar 2020 10:09:48 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j8mhW-0003n2-KB for qemu-devel@nongnu.org; Mon, 02 Mar 2020 10:09:47 -0500 Received: from relay.sw.ru ([185.231.240.75]:33796) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j8mhT-0003m9-M3; Mon, 02 Mar 2020 10:09:43 -0500 Received: from vovaso.qa.sw.ru ([10.94.3.0] helo=kvm.qa.sw.ru) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1j8mhK-0006IJ-6c; Mon, 02 Mar 2020 18:09:34 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Subject: [PATCH] block/qcow2-threads: fix qcow2_decompress Date: Mon, 2 Mar 2020 18:09:30 +0300 Message-Id: <20200302150930.16218-1-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 185.231.240.75 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, vsementsov@virtuozzo.com, qemu-stable@nongnu.org, qemu-devel@nongnu.org, dplotnikov@virtuozzo.com, mreitz@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" On success path we return what inflate() returns instead of 0. And it most probably works for Z_STREAM_END as it is positive, but is definitely broken for Z_BUF_ERROR. While being here, switch to errno return code, to be closer to qcow2_compress API (and usual expectations). Revert condition in if to be more positive. Drop dead initialization of ret. Cc: qemu-stable@nongnu.org # v4.0 Fixes: 341926ab83e2b Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Alberto Garcia Reviewed-by: Ján Tomko --- Hi! Reviewing Den's series about zstd in qcow2 support, I found an existing bug. Let's fix it. This is to be a new base of zstd series. block/qcow2-threads.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/block/qcow2-threads.c b/block/qcow2-threads.c index 8f5a0d1ebe..0d193d1614 100644 --- a/block/qcow2-threads.c +++ b/block/qcow2-threads.c @@ -128,12 +128,12 @@ static ssize_t qcow2_compress(void *dest, size_t dest_size, * @src - source buffer, @src_size bytes * * Returns: 0 on success - * -1 on fail + * -EIO on fail */ static ssize_t qcow2_decompress(void *dest, size_t dest_size, const void *src, size_t src_size) { - int ret = 0; + int ret; z_stream strm; memset(&strm, 0, sizeof(strm)); @@ -144,17 +144,19 @@ static ssize_t qcow2_decompress(void *dest, size_t dest_size, ret = inflateInit2(&strm, -12); if (ret != Z_OK) { - return -1; + return -EIO; } ret = inflate(&strm, Z_FINISH); - if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || strm.avail_out != 0) { + if ((ret == Z_STREAM_END || ret == Z_BUF_ERROR) && strm.avail_out == 0) { /* * We approve Z_BUF_ERROR because we need @dest buffer to be filled, but * @src buffer may be processed partly (because in qcow2 we know size of * compressed data with precision of one sector) */ - ret = -1; + ret = 0; + } else { + ret = -EIO; } inflateEnd(&strm);