iotests: Add test for checking large image files

#!/bin/bash

#

# General test case for qcow2's image check

#

# Copyright (C) 2015 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 <http://www.gnu.org/licenses/>.

#

# creator

owner=mreitz@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

# This tests qocw2-specific low-level functionality

_supported_fmt qcow2

_supported_proto file

_supported_os Linux

echo

echo '=== Check on an image with a multiple of 2^32 clusters ==='

echo

IMGOPTS=$(_optstr_add "$IMGOPTS" "cluster_size=512") \

    _make_test_img 512

# Allocate L2 table

$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io

# Put the data cluster at a multiple of 2 TB, resulting in the image apparently

# having a multiple of 2^32 clusters

# (To be more specific: It is at 32 PB)

poke_file "$TEST_IMG" 2048 "\x80\x80\x00\x00\x00\x00\x00\x00"

# An offset of 32 PB results in qemu-img check having to allocate an in-memory

# refcount table of 128 TB (16 bit refcounts, 512 byte clusters).

# This should be generally too much for any system and thus fail.

# What this test is checking is that the qcow2 driver actually tries to allocate

# such a large amount of memory (and is consequently aborting) instead of having

# truncated the cluster count somewhere (which would result in much less memory

# being allocated and then a segfault occurring).

_check_test_img

# success, all done

echo "*** done"

rm -f $seq.full

status=0

QA output created by 138

=== Check on an image with a multiple of 2^32 clusters ===

Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=512

wrote 512/512 bytes at offset 0

512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

qemu-img: Check failed: Cannot allocate memory

*** done

134 rw auto quick

135 rw auto

137 rw auto

138 rw auto quick