[Qemu-devel] [PATCH 5/5] qemu-iotests: Overlapping cluster allocations

[Max Reitz]

A new test on corrupted images with overlapping cluster allocations.

Signed-off-by: Max Reitz <address@hidden>
---
 tests/qemu-iotests/060     | 107 +++++++++++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/060.out |  43 ++++++++++++++++++
 tests/qemu-iotests/group   |   1 +
 3 files changed, 151 insertions(+)
 create mode 100755 tests/qemu-iotests/060
 create mode 100644 tests/qemu-iotests/060.out

diff --git a/tests/qemu-iotests/060 b/tests/qemu-iotests/060
new file mode 100755
index 0000000..2dd6711
--- /dev/null
+++ b/tests/qemu-iotests/060
@@ -0,0 +1,107 @@
+#!/bin/bash
+#
+# Test case for image corruption (overlapping data structures) in qcow2
+#
+# Copyright (C) 2013 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
address@hidden
+
+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 generic
+_supported_os Linux
+
+rt_offset=65536  # 0x10000 (XXX: just an assumption)
+rb_offset=131072 # 0x20000 (XXX: just an assumption)
+l1_offset=196608 # 0x30000 (XXX: just an assumption)
+l2_offset=262144 # 0x40000 (XXX: just an assumption)
+
+IMGOPTS="compat=1.1"
+
+echo
+echo "=== Testing L2 reference into L1 ==="
+echo
+_make_test_img 64M
+# Link first L1 entry (first L2 table) onto itself
+# (Note the MSb in the L1 entry is set, ensuring the refcount is one - else any
+# later write will result in a COW operation, effectively ruining this attempt
+# on image corruption)
+poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x03\x00\x00"
+_check_test_img
+
+# The corrupt bit should not be set anyway
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+# Try to write something, thereby forcing the corrupt bit to be set
+$QEMU_IO -c "write -P 0x2a 0 512" "$TEST_IMG" | _filter_qemu_io
+
+# The corrupt bit must now be set
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+# We could now try to fix the image, but this would probably fail (how should 
an
+# L2 table linked onto the L1 table be fixed?)
+
+echo
+echo "=== Testing cluster data reference into refcount block ==="
+echo
+_make_test_img 64M
+# Allocate L2 table
+truncate -s "$(($l2_offset+65536))" "$TEST_IMG"
+poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x00\x00"
+# Mark cluster as used
+poke_file "$TEST_IMG" "$(($rb_offset+8))" "\x00\x01"
+# Redirect new data cluster onto refcount block
+poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x02\x00\x00"
+_check_test_img
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+$QEMU_IO -c "write -P 0x2a 0 512" "$TEST_IMG" | _filter_qemu_io
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+cp $TEST_IMG foo.qcow2
+
+# Try to fix it
+_check_test_img -r all
+
+# The corrupt bit should be cleared
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+# Look if it's really really fixed
+$QEMU_IO -c "write -P 0x2a 0 512" "$TEST_IMG" | _filter_qemu_io
+./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/060.out b/tests/qemu-iotests/060.out
new file mode 100644
index 0000000..10feced
--- /dev/null
+++ b/tests/qemu-iotests/060.out
@@ -0,0 +1,43 @@
+QA output created by 060
+
+=== Testing L2 reference into L1 ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+ERROR cluster 3 refcount=1 reference=3
+ERROR L2 0 overlaps with active L1 table
+
+2 errors were found on the image.
+Data may be corrupted, or further writes to the image may corrupt it.
+incompatible_features     0x0
+qcow2: Preventing invalid write on metadata; image marked as corrupt.
+write failed: Input/output error
+incompatible_features     0x2
+
+=== Testing cluster data reference into refcount block ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+ERROR refcount block 0 refcount=2
+ERROR cluster 2 refcount=1 reference=2
+ERROR data cluster 0x0 overlaps with refcount block
+
+3 errors were found on the image.
+Data may be corrupted, or further writes to the image may corrupt it.
+incompatible_features     0x0
+qcow2: Preventing invalid write on metadata; image marked as corrupt.
+write failed: Input/output error
+incompatible_features     0x2
+ERROR refcount block 0 refcount=2
+Repairing cluster 2 refcount=1 reference=2
+Reallocating data cluster 0x0 (currently overlapping with refcount block)
+The following inconsistencies were found and repaired:
+
+    0 leaked clusters
+    2 corruptions
+
+Double checking the fixed image now...
+No errors were found on the image.
+incompatible_features     0x0
+wrote 512/512 bytes at offset 0
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+incompatible_features     0x0
+*** done
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 43c05d6..0845eb5 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -64,3 +64,4 @@
 055 rw auto
 056 rw auto backing
 059 rw auto
+060 rw auto
-- 
1.8.3.1