tests/qemu-iotests/060

   1 #!/bin/bash
   2 #
   3 # Test case for image corruption (overlapping data structures) in qcow2
   4 #
   5 # Copyright (C) 2013 Red Hat, Inc.
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 #
  20
  21 # creator
  22 owner=mreitz@redhat.com
  23
  24 seq="$(basename $0)"
  25 echo "QA output created by $seq"
  26
  27 here="$PWD"
  28 tmp=/tmp/$$
  29 status=1        # failure is the default!
  30
  31 _cleanup()
  32 {
  33         _cleanup_test_img
  34 }
  35 trap "_cleanup; exit \$status" 0 1 2 3 15
  36
  37 # get standard environment, filters and checks
  38 . ./common.rc
  39 . ./common.filter
  40
  41 # This tests qocw2-specific low-level functionality
  42 _supported_fmt qcow2
  43 _supported_proto file
  44 _supported_os Linux
  45
  46 rt_offset=65536  # 0x10000 (XXX: just an assumption)
  47 rb_offset=131072 # 0x20000 (XXX: just an assumption)
  48 l1_offset=196608 # 0x30000 (XXX: just an assumption)
  49 l2_offset=262144 # 0x40000 (XXX: just an assumption)
  50 l2_offset_after_snapshot=524288 # 0x80000 (XXX: just an assumption)
  51
  52 IMGOPTS="compat=1.1"
  53
  54 OPEN_RW="open -o overlap-check=all $TEST_IMG"
  55 # Overlap checks are done before write operations only, therefore opening an
  56 # image read-only makes the overlap-check option irrelevant
  57 OPEN_RO="open -r $TEST_IMG"
  58
  59 echo
  60 echo "=== Testing L2 reference into L1 ==="
  61 echo
  62 _make_test_img 64M
  63 # Link first L1 entry (first L2 table) onto itself
  64 # (Note the MSb in the L1 entry is set, ensuring the refcount is one - else any
  65 # later write will result in a COW operation, effectively ruining this attempt
  66 # on image corruption)
  67 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x03\x00\x00"
  68 _check_test_img
  69
  70 # The corrupt bit should not be set anyway
  71 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
  72
  73 # Try to write something, thereby forcing the corrupt bit to be set
  74 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
  75
  76 # The corrupt bit must now be set
  77 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
  78
  79 # This information should be available through qemu-img info
  80 _img_info --format-specific
  81
  82 # Try to open the image R/W (which should fail)
  83 $QEMU_IO -c "$OPEN_RW" -c "read 0 512" 2>&1 | _filter_qemu_io \
  84                                             | _filter_testdir \
  85                                             | _filter_imgfmt
  86
  87 # Try to open it RO (which should succeed)
  88 $QEMU_IO -c "$OPEN_RO" -c "read 0 512" | _filter_qemu_io
  89
  90 # We could now try to fix the image, but this would probably fail (how should an
  91 # L2 table linked onto the L1 table be fixed?)
  92
  93 echo
  94 echo "=== Testing cluster data reference into refcount block ==="
  95 echo
  96 _make_test_img 64M
  97 # Allocate L2 table
  98 truncate -s "$(($l2_offset+65536))" "$TEST_IMG"
  99 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x00\x00"
 100 # Mark cluster as used
 101 poke_file "$TEST_IMG" "$(($rb_offset+8))" "\x00\x01"
 102 # Redirect new data cluster onto refcount block
 103 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x02\x00\x00"
 104 _check_test_img
 105 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 106 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
 107 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 108
 109 # Try to fix it
 110 _check_test_img -r all
 111
 112 # The corrupt bit should be cleared
 113 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 114
 115 # Look if it's really really fixed
 116 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
 117 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 118
 119 echo
 120 echo "=== Testing cluster data reference into inactive L2 table ==="
 121 echo
 122 _make_test_img 64M
 123 $QEMU_IO -c "$OPEN_RW" -c "write -P 1 0 512" | _filter_qemu_io
 124 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 125 $QEMU_IO -c "$OPEN_RW" -c "write -P 2 0 512" | _filter_qemu_io
 126 # The inactive L2 table remains at its old offset
 127 poke_file "$TEST_IMG" "$l2_offset_after_snapshot" \
 128                       "\x80\x00\x00\x00\x00\x04\x00\x00"
 129 _check_test_img
 130 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 131 $QEMU_IO -c "$OPEN_RW" -c "write -P 3 0 512" | _filter_qemu_io
 132 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 133 _check_test_img -r all
 134 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 135 $QEMU_IO -c "$OPEN_RW" -c "write -P 4 0 512" | _filter_qemu_io
 136 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 137
 138 # Check data
 139 $QEMU_IO -c "$OPEN_RO" -c "read -P 4 0 512" | _filter_qemu_io
 140 $QEMU_IMG snapshot -a foo "$TEST_IMG"
 141 _check_test_img
 142 $QEMU_IO -c "$OPEN_RO" -c "read -P 1 0 512" | _filter_qemu_io
 143
 144 echo
 145 echo "=== Testing overlap while COW is in flight ==="
 146 echo
 147 # compat=0.10 is required in order to make the following discard actually
 148 # unallocate the sector rather than make it a zero sector - we want COW, after
 149 # all.
 150 IMGOPTS='compat=0.10' _make_test_img 1G
 151 # Write two clusters, the second one enforces creation of an L2 table after
 152 # the first data cluster.
 153 $QEMU_IO -c 'write 0k 64k' -c 'write 512M 64k' "$TEST_IMG" | _filter_qemu_io
 154 # Discard the first cluster. This cluster will soon enough be reallocated and
 155 # used for COW.
 156 $QEMU_IO -c 'discard 0k 64k' "$TEST_IMG" | _filter_qemu_io
 157 # Now, corrupt the image by marking the second L2 table cluster as free.
 158 poke_file "$TEST_IMG" '131084' "\x00\x00" # 0x2000c
 159 # Start a write operation requiring COW on the image stopping it right before
 160 # doing the read; then, trigger the corruption prevention by writing anything to
 161 # any unallocated cluster, leading to an attempt to overwrite the second L2
 162 # table. Finally, resume the COW write and see it fail (but not crash).
 163 echo "open -o file.driver=blkdebug $TEST_IMG
 164 break cow_read 0
 165 aio_write 0k 1k
 166 wait_break 0
 167 write 64k 64k
 168 resume 0" | $QEMU_IO | _filter_qemu_io
 169
 170 echo
 171 echo "=== Testing unallocated image header ==="
 172 echo
 173 _make_test_img 64M
 174 # Create L1/L2
 175 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 176 poke_file "$TEST_IMG" "$rb_offset" "\x00\x00"
 177 $QEMU_IO -c "write 64k 64k" "$TEST_IMG" | _filter_qemu_io
 178
 179 echo
 180 echo "=== Testing unaligned L1 entry ==="
 181 echo
 182 _make_test_img 64M
 183 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 184 # This will be masked with ~(512 - 1) = ~0x1ff, so whether the lower 9 bits are
 185 # aligned or not does not matter
 186 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x2a\x00"
 187 $QEMU_IO -c "read 0 64k" "$TEST_IMG" | _filter_qemu_io
 188
 189 # Test how well zero cluster expansion can cope with this
 190 _make_test_img 64M
 191 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 192 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x2a\x00"
 193 $QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
 194
 195 echo
 196 echo "=== Testing unaligned L2 entry ==="
 197 echo
 198 _make_test_img 64M
 199 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 200 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 201 $QEMU_IO -c "read 0 64k" "$TEST_IMG" | _filter_qemu_io
 202
 203 echo
 204 echo "=== Testing unaligned pre-allocated zero cluster ==="
 205 echo
 206 _make_test_img 64M
 207 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 208 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x01"
 209 # zero cluster expansion
 210 $QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
 211
 212 echo
 213 echo "=== Testing unaligned reftable entry ==="
 214 echo
 215 _make_test_img 64M
 216 poke_file "$TEST_IMG" "$rt_offset" "\x00\x00\x00\x00\x00\x02\x2a\x00"
 217 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 218
 219 echo
 220 echo "=== Testing non-fatal corruption on freeing ==="
 221 echo
 222 _make_test_img 64M
 223 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 224 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 225 $QEMU_IO -c "discard 0 64k" "$TEST_IMG" | _filter_qemu_io
 226
 227 echo
 228 echo "=== Testing read-only corruption report ==="
 229 echo
 230 _make_test_img 64M
 231 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 232 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 233 # Should only emit a single error message
 234 $QEMU_IO -c "$OPEN_RO" -c "read 0 64k" -c "read 0 64k" | _filter_qemu_io
 235
 236 echo
 237 echo "=== Testing non-fatal and then fatal corruption report ==="
 238 echo
 239 _make_test_img 64M
 240 $QEMU_IO -c "write 0 128k" "$TEST_IMG" | _filter_qemu_io
 241 poke_file "$TEST_IMG" "$l2_offset"        "\x80\x00\x00\x00\x00\x05\x2a\x00"
 242 poke_file "$TEST_IMG" "$(($l2_offset+8))" "\x80\x00\x00\x00\x00\x06\x2a\x00"
 243 # Should emit two error messages
 244 $QEMU_IO -c "discard 0 64k" -c "read 64k 64k" "$TEST_IMG" | _filter_qemu_io
 245
 246 # success, all done
 247 echo "*** done"
 248 rm -f $seq.full
 249 status=0