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 status=1        # failure is the default!
  29
  30 _cleanup()
  31 {
  32         _cleanup_test_img
  33 }
  34 trap "_cleanup; exit \$status" 0 1 2 3 15
  35
  36 # get standard environment, filters and checks
  37 . ./common.rc
  38 . ./common.filter
  39
  40 # This tests qocw2-specific low-level functionality
  41 _supported_fmt qcow2
  42 _supported_proto file
  43 _supported_os Linux
  44
  45 rt_offset=65536  # 0x10000 (XXX: just an assumption)
  46 rb_offset=131072 # 0x20000 (XXX: just an assumption)
  47 l1_offset=196608 # 0x30000 (XXX: just an assumption)
  48 l2_offset=262144 # 0x40000 (XXX: just an assumption)
  49 l2_offset_after_snapshot=524288 # 0x80000 (XXX: just an assumption)
  50
  51 IMGOPTS="compat=1.1"
  52
  53 OPEN_RW="open -o overlap-check=all $TEST_IMG"
  54 # Overlap checks are done before write operations only, therefore opening an
  55 # image read-only makes the overlap-check option irrelevant
  56 OPEN_RO="open -r $TEST_IMG"
  57
  58 echo
  59 echo "=== Testing L2 reference into L1 ==="
  60 echo
  61 _make_test_img 64M
  62 # Link first L1 entry (first L2 table) onto itself
  63 # (Note the MSb in the L1 entry is set, ensuring the refcount is one - else any
  64 # later write will result in a COW operation, effectively ruining this attempt
  65 # on image corruption)
  66 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x03\x00\x00"
  67 _check_test_img
  68
  69 # The corrupt bit should not be set anyway
  70 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
  71
  72 # Try to write something, thereby forcing the corrupt bit to be set
  73 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
  74
  75 # The corrupt bit must now be set
  76 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
  77
  78 # This information should be available through qemu-img info
  79 _img_info --format-specific
  80
  81 # Try to open the image R/W (which should fail)
  82 $QEMU_IO -c "$OPEN_RW" -c "read 0 512" 2>&1 | _filter_qemu_io \
  83                                             | _filter_testdir \
  84                                             | _filter_imgfmt
  85
  86 # Try to open it RO (which should succeed)
  87 $QEMU_IO -c "$OPEN_RO" -c "read 0 512" | _filter_qemu_io
  88
  89 # We could now try to fix the image, but this would probably fail (how should an
  90 # L2 table linked onto the L1 table be fixed?)
  91
  92 echo
  93 echo "=== Testing cluster data reference into refcount block ==="
  94 echo
  95 _make_test_img 64M
  96 # Allocate L2 table
  97 truncate -s "$(($l2_offset+65536))" "$TEST_IMG"
  98 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x00\x00"
  99 # Mark cluster as used
 100 poke_file "$TEST_IMG" "$(($rb_offset+8))" "\x00\x01"
 101 # Redirect new data cluster onto refcount block
 102 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x02\x00\x00"
 103 _check_test_img
 104 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 105 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
 106 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 107
 108 # Try to fix it
 109 _check_test_img -r all
 110
 111 # The corrupt bit should be cleared
 112 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 113
 114 # Look if it's really really fixed
 115 $QEMU_IO -c "$OPEN_RW" -c "write -P 0x2a 0 512" | _filter_qemu_io
 116 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 117
 118 echo
 119 echo "=== Testing cluster data reference into inactive L2 table ==="
 120 echo
 121 _make_test_img 64M
 122 $QEMU_IO -c "$OPEN_RW" -c "write -P 1 0 512" | _filter_qemu_io
 123 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 124 $QEMU_IO -c "$OPEN_RW" -c "write -P 2 0 512" | _filter_qemu_io
 125 # The inactive L2 table remains at its old offset
 126 poke_file "$TEST_IMG" "$l2_offset_after_snapshot" \
 127                       "\x80\x00\x00\x00\x00\x04\x00\x00"
 128 _check_test_img
 129 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 130 $QEMU_IO -c "$OPEN_RW" -c "write -P 3 0 512" | _filter_qemu_io
 131 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 132 _check_test_img -r all
 133 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 134 $QEMU_IO -c "$OPEN_RW" -c "write -P 4 0 512" | _filter_qemu_io
 135 $PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
 136
 137 # Check data
 138 $QEMU_IO -c "$OPEN_RO" -c "read -P 4 0 512" | _filter_qemu_io
 139 $QEMU_IMG snapshot -a foo "$TEST_IMG"
 140 _check_test_img
 141 $QEMU_IO -c "$OPEN_RO" -c "read -P 1 0 512" | _filter_qemu_io
 142
 143 echo
 144 echo "=== Testing overlap while COW is in flight ==="
 145 echo
 146 # compat=0.10 is required in order to make the following discard actually
 147 # unallocate the sector rather than make it a zero sector - we want COW, after
 148 # all.
 149 IMGOPTS='compat=0.10' _make_test_img 1G
 150 # Write two clusters, the second one enforces creation of an L2 table after
 151 # the first data cluster.
 152 $QEMU_IO -c 'write 0k 64k' -c 'write 512M 64k' "$TEST_IMG" | _filter_qemu_io
 153 # Discard the first cluster. This cluster will soon enough be reallocated and
 154 # used for COW.
 155 $QEMU_IO -c 'discard 0k 64k' "$TEST_IMG" | _filter_qemu_io
 156 # Now, corrupt the image by marking the second L2 table cluster as free.
 157 poke_file "$TEST_IMG" '131084' "\x00\x00" # 0x2000c
 158 # Start a write operation requiring COW on the image stopping it right before
 159 # doing the read; then, trigger the corruption prevention by writing anything to
 160 # any unallocated cluster, leading to an attempt to overwrite the second L2
 161 # table. Finally, resume the COW write and see it fail (but not crash).
 162 echo "open -o file.driver=blkdebug $TEST_IMG
 163 break cow_read 0
 164 aio_write 0k 1k
 165 wait_break 0
 166 write 64k 64k
 167 resume 0" | $QEMU_IO | _filter_qemu_io
 168
 169 echo
 170 echo "=== Testing unallocated image header ==="
 171 echo
 172 _make_test_img 64M
 173 # Create L1/L2
 174 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 175 poke_file "$TEST_IMG" "$rb_offset" "\x00\x00"
 176 $QEMU_IO -c "write 64k 64k" "$TEST_IMG" | _filter_qemu_io
 177
 178 echo
 179 echo "=== Testing unaligned L1 entry ==="
 180 echo
 181 _make_test_img 64M
 182 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 183 # This will be masked with ~(512 - 1) = ~0x1ff, so whether the lower 9 bits are
 184 # aligned or not does not matter
 185 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x2a\x00"
 186 $QEMU_IO -c "read 0 64k" "$TEST_IMG" | _filter_qemu_io
 187
 188 # Test how well zero cluster expansion can cope with this
 189 _make_test_img 64M
 190 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 191 poke_file "$TEST_IMG" "$l1_offset" "\x80\x00\x00\x00\x00\x04\x2a\x00"
 192 $QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
 193
 194 echo
 195 echo "=== Testing unaligned L2 entry ==="
 196 echo
 197 _make_test_img 64M
 198 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 199 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 200 $QEMU_IO -c "read 0 64k" "$TEST_IMG" | _filter_qemu_io
 201
 202 echo
 203 echo "=== Testing unaligned pre-allocated zero cluster ==="
 204 echo
 205 _make_test_img 64M
 206 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 207 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x01"
 208 # zero cluster expansion
 209 $QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
 210
 211 echo
 212 echo "=== Testing unaligned reftable entry ==="
 213 echo
 214 _make_test_img 64M
 215 poke_file "$TEST_IMG" "$rt_offset" "\x00\x00\x00\x00\x00\x02\x2a\x00"
 216 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 217
 218 echo
 219 echo "=== Testing non-fatal corruption on freeing ==="
 220 echo
 221 _make_test_img 64M
 222 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 223 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 224 $QEMU_IO -c "discard 0 64k" "$TEST_IMG" | _filter_qemu_io
 225
 226 echo
 227 echo "=== Testing read-only corruption report ==="
 228 echo
 229 _make_test_img 64M
 230 $QEMU_IO -c "write 0 64k" "$TEST_IMG" | _filter_qemu_io
 231 poke_file "$TEST_IMG" "$l2_offset" "\x80\x00\x00\x00\x00\x05\x2a\x00"
 232 # Should only emit a single error message
 233 $QEMU_IO -c "$OPEN_RO" -c "read 0 64k" -c "read 0 64k" | _filter_qemu_io
 234
 235 echo
 236 echo "=== Testing non-fatal and then fatal corruption report ==="
 237 echo
 238 _make_test_img 64M
 239 $QEMU_IO -c "write 0 128k" "$TEST_IMG" | _filter_qemu_io
 240 poke_file "$TEST_IMG" "$l2_offset"        "\x80\x00\x00\x00\x00\x05\x2a\x00"
 241 poke_file "$TEST_IMG" "$(($l2_offset+8))" "\x80\x00\x00\x00\x00\x06\x2a\x00"
 242 # Should emit two error messages
 243 $QEMU_IO -c "discard 0 64k" -c "read 64k 64k" "$TEST_IMG" | _filter_qemu_io
 244
 245 # success, all done
 246 echo "*** done"
 247 rm -f $seq.full
 248 status=0