From 5f0681e1c3f47c680ca31fea4c7627648aedabdf Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 25 Nov 2014 18:12:42 +0100 Subject: [PATCH] block: Don't probe for unknown backing file format If a qcow2 image specifies a backing file format that doesn't correspond to any format driver that qemu knows, we shouldn't fall back to probing, but simply error out. Not looking up the backing file driver in bdrv_open_backing_file(), but just filling in the "driver" option if it isn't there moves us closer to the goal of having everything in QDict options and gets us the error handling of bdrv_open(), which correctly refuses unknown drivers. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz Message-id: 1416935562-7760-4-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf (cherry picked from commit c5f6e493bb5339d244eae5d3f21c5b6d73996739) Conflicts: tests/qemu-iotests/group *removed context from upstream iotest groups Signed-off-by: Michael Roth --- block.c | 7 ++--- tests/qemu-iotests/114 | 61 ++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/114.out | 13 ++++++++ tests/qemu-iotests/group | 1 + 4 files changed, 78 insertions(+), 4 deletions(-) create mode 100755 tests/qemu-iotests/114 create mode 100644 tests/qemu-iotests/114.out diff --git a/block.c b/block.c index f6c8de465f54..ed87b7eb8e80 100644 --- a/block.c +++ b/block.c @@ -1177,7 +1177,6 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) { char *backing_filename = g_malloc0(PATH_MAX); int ret = 0; - BlockDriver *back_drv = NULL; BlockDriverState *backing_hd; Error *local_err = NULL; @@ -1210,14 +1209,14 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) backing_hd = bdrv_new("", errp); - if (bs->backing_format[0] != '\0') { - back_drv = bdrv_find_format(bs->backing_format); + if (bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) { + qdict_put(options, "driver", qstring_from_str(bs->backing_format)); } assert(bs->backing_hd == NULL); ret = bdrv_open(&backing_hd, *backing_filename ? backing_filename : NULL, NULL, options, - bdrv_backing_flags(bs->open_flags), back_drv, &local_err); + bdrv_backing_flags(bs->open_flags), NULL, &local_err); if (ret < 0) { bdrv_unref(backing_hd); backing_hd = NULL; diff --git a/tests/qemu-iotests/114 b/tests/qemu-iotests/114 new file mode 100755 index 000000000000..d02e7ffbe3f6 --- /dev/null +++ b/tests/qemu-iotests/114 @@ -0,0 +1,61 @@ +#!/bin/bash +# +# Test invalid backing file format in qcow2 images +# +# Copyright (C) 2014 Red Hat, Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . +# + +# creator +owner=kwolf@redhat.com + +seq="$(basename $0)" +echo "QA output created by $seq" + +here="$PWD" +tmp=/tmp/$$ +status=1 # failure is the default! + +_cleanup() +{ + _cleanup_test_img +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common.rc +. ./common.filter + +_supported_fmt qcow2 +_supported_proto generic +_supported_os Linux + + +TEST_IMG="$TEST_IMG.base" _make_test_img 64M +_make_test_img -b "$TEST_IMG.base" 64M + +# Set an invalid backing file format +$PYTHON qcow2.py "$TEST_IMG" add-header-ext 0xE2792ACA "foo" +_img_info + +# Try opening the image. Should fail (and not probe) in the first case, but +# overriding the backing file format should be possible. +$QEMU_IO -c "open $TEST_IMG" -c "read 0 4k" 2>&1 | _filter_qemu_io | _filter_testdir +$QEMU_IO -c "open -o backing.driver=$IMGFMT $TEST_IMG" -c "read 0 4k" | _filter_qemu_io + +# success, all done +echo '*** done' +rm -f $seq.full +status=0 diff --git a/tests/qemu-iotests/114.out b/tests/qemu-iotests/114.out new file mode 100644 index 000000000000..6c6b21085afe --- /dev/null +++ b/tests/qemu-iotests/114.out @@ -0,0 +1,13 @@ +QA output created by 114 +Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 backing_file='TEST_DIR/t.IMGFMT.base' +image: TEST_DIR/t.IMGFMT +file format: IMGFMT +virtual size: 64M (67108864 bytes) +cluster_size: 65536 +backing file: TEST_DIR/t.IMGFMT.base +backing file format: foo +qemu-io: can't open device TEST_DIR/t.qcow2: Could not open backing file: Unknown driver 'foo' +read 4096/4096 bytes at offset 0 +4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +*** done diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group index 4bb70d723f44..97026f31a5cc 100644 --- a/tests/qemu-iotests/group +++ b/tests/qemu-iotests/group @@ -102,3 +102,4 @@ 095 rw auto quick 101 rw auto quick 113 rw auto quick +114 rw auto quick