From 82b45e0a0b824787bd79ce3f6453eaa2afddd138 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 28 Feb 2018 14:13:14 +0100 Subject: block/file-posix: Fix fully preallocated truncate Storing the lseek() result in an int results in it overflowing when the file is at least 2 GB big. Then, we have a 50 % chance of the result being "negative" and thus thinking an error occurred when actually everything went just fine. So we should use the correct type for storing the result: off_t. Reported-by: Daniel P. Berrange Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1549231 Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz Message-id: 20180228131315.30194-2-mreitz@redhat.com Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- block/file-posix.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index a2f6d8a8c8..3794c0007a 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1701,6 +1701,7 @@ static int raw_regular_truncate(int fd, int64_t offset, PreallocMode prealloc, case PREALLOC_MODE_FULL: { int64_t num = 0, left = offset - current_length; + off_t seek_result; /* * Knowing the final size from the beginning could allow the file @@ -1715,8 +1716,8 @@ static int raw_regular_truncate(int fd, int64_t offset, PreallocMode prealloc, buf = g_malloc0(65536); - result = lseek(fd, current_length, SEEK_SET); - if (result < 0) { + seek_result = lseek(fd, current_length, SEEK_SET); + if (seek_result < 0) { result = -errno; error_setg_errno(errp, -result, "Failed to seek to the old end of file"); -- cgit v1.2.3 From 733d1dce0f3c8ab7b79a173f6482781d3718f844 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 28 Feb 2018 14:13:15 +0100 Subject: iotests: Test preallocated truncate of 2G image MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Max Reitz Message-id: 20180228131315.30194-3-mreitz@redhat.com Reviewed-by: Daniel P. Berrangé Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- tests/qemu-iotests/106 | 24 ++++++++++++++++++++++++ tests/qemu-iotests/106.out | 10 ++++++++++ 2 files changed, 34 insertions(+) diff --git a/tests/qemu-iotests/106 b/tests/qemu-iotests/106 index bfe71f4e60..5e51f88a78 100755 --- a/tests/qemu-iotests/106 +++ b/tests/qemu-iotests/106 @@ -86,6 +86,30 @@ for growth_mode in falloc full off; do $QEMU_IMG resize -f "$IMGFMT" --shrink --preallocation=$growth_mode "$TEST_IMG" -${GROWTH_SIZE}K done +echo +echo '=== Testing image growth on 2G empty image ===' + +for growth_mode in falloc full; do + echo + echo "--- growth_mode=$growth_mode ---" + + # Maybe we want to do an lseek() to the end of the file before the + # preallocation; if the file has a length of 2 GB, that would + # return an integer that overflows to negative when put into a + # plain int. We should use the correct type for the result, and + # this tests we do. + + _make_test_img 2G + $QEMU_IMG resize -f "$IMGFMT" --preallocation=$growth_mode "$TEST_IMG" +${GROWTH_SIZE}K + + actual_size=$($QEMU_IMG info -f "$IMGFMT" "$TEST_IMG" | grep 'disk size') + actual_size=$(echo "$actual_size" | sed -e 's/^[^0-9]*\([0-9]\+\).*$/\1/') + + if [ $actual_size -lt $GROWTH_SIZE ]; then + echo "ERROR: Image should have at least ${GROWTH_SIZE}K, but has ${actual_size}K" + fi +done + # success, all done echo '*** done' rm -f $seq.full diff --git a/tests/qemu-iotests/106.out b/tests/qemu-iotests/106.out index 0a42312301..c459957660 100644 --- a/tests/qemu-iotests/106.out +++ b/tests/qemu-iotests/106.out @@ -47,4 +47,14 @@ qemu-img: Preallocation can only be used for growing images --- growth_mode=off --- Image resized. + +=== Testing image growth on 2G empty image === + +--- growth_mode=falloc --- +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648 +Image resized. + +--- growth_mode=full --- +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648 +Image resized. *** done -- cgit v1.2.3 From 96914159b7c4f9cd574301517c15b0743a050f95 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Luk=C3=A1=C5=A1=20Doktor?= Date: Thu, 29 Mar 2018 13:20:53 +0200 Subject: qemu-iotests: Use ppc64 qemu_arch on ppc64le host MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The qemu target does not always correspond to the host machine type. For example ppc64le machine target is ppc64. Let's introduce "qemu_arch" variable to store the matching qemu architecture related to the current architecture and use it when auto-detecting the default qemu binary. Signed-off-by: Lukáš Doktor Message-id: 20180329112053.5399-2-ldoktor@redhat.com Signed-off-by: Max Reitz --- tests/qemu-iotests/check | 4 ++-- tests/qemu-iotests/common.config | 1 + 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check index ec8033350d..aa94c6c7ea 100755 --- a/tests/qemu-iotests/check +++ b/tests/qemu-iotests/check @@ -538,8 +538,8 @@ if [ -z "$QEMU_PROG" ] then if [ -x "$build_iotests/qemu" ]; then export QEMU_PROG="$build_iotests/qemu" - elif [ -x "$build_root/$arch-softmmu/qemu-system-$arch" ]; then - export QEMU_PROG="$build_root/$arch-softmmu/qemu-system-$arch" + elif [ -x "$build_root/${qemu_arch}-softmmu/qemu-system-${qemu_arch}" ]; then + export QEMU_PROG="$build_root/${qemu_arch}-softmmu/qemu-system-${qemu_arch}" else pushd "$build_root" > /dev/null for binary in *-softmmu/qemu-system-* diff --git a/tests/qemu-iotests/common.config b/tests/qemu-iotests/common.config index cdcda54546..102aa6878a 100644 --- a/tests/qemu-iotests/common.config +++ b/tests/qemu-iotests/common.config @@ -23,6 +23,7 @@ PATH=".:$PATH" HOSTOS=`uname -s` arch=`uname -m` +[[ "$arch" =~ "ppc64" ]] && qemu_arch=ppc64 || qemu_arch="$arch" export PWD=`pwd` -- cgit v1.2.3 From abd3622cc03cf41ed542126a540385f30a4c0175 Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Thu, 29 Mar 2018 15:07:45 +0300 Subject: iotests: Test abnormally large size in compressed cluster descriptor L2 entries for compressed clusters have a field that indicates the number of sectors used to store the data in the image. That's however not the size of the compressed data itself, just the number of sectors where that data is located. The actual data size is usually not a multiple of the sector size, and therefore cannot be represented with this field. The way it works is that QEMU reads all the specified sectors and starts decompressing the data until there's enough to recover the original uncompressed cluster. If there are any bytes left that haven't been decompressed they are simply ignored. One consequence of this is that even if the size field is larger than it needs to be QEMU can handle it just fine: it will read more data from disk but it will ignore the extra bytes. This test creates an image with two compressed clusters that use 5 sectors (2.5 KB) each, increases the size field to the maximum (8192 sectors, or 4 MB) and verifies that the data can be read without problems. This test is important because while the decompressed data takes exactly one cluster, the maximum value allowed in the compressed size field is twice the cluster size. So although QEMU won't produce images with such large values we need to make sure that it can handle them. Another effect of increasing the size field is that it can make it include data from the following host cluster(s). In this case 'qemu-img check' will detect that the refcounts are not correct, and we'll need to rebuild them. Additionally, this patch also tests that decreasing the size corrupts the image since the original data can no longer be recovered. In this case QEMU returns an error when trying to read the compressed data, but 'qemu-img check' doesn't see anything wrong if the refcounts are consistent. One possible task for the future is to make 'qemu-img check' verify the sizes of the compressed clusters, by trying to decompress the data and checking that the size stored in the L2 entry is correct. Signed-off-by: Alberto Garcia Message-id: 20180329120745.11154-1-berto@igalia.com Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- tests/qemu-iotests/122 | 47 ++++++++++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/122.out | 33 ++++++++++++++++++++++++++++++++ 2 files changed, 80 insertions(+) diff --git a/tests/qemu-iotests/122 b/tests/qemu-iotests/122 index 45b359c2ba..6cf4fcb866 100755 --- a/tests/qemu-iotests/122 +++ b/tests/qemu-iotests/122 @@ -129,6 +129,53 @@ $QEMU_IO -c "read -P 0x44 1023k 1k" "$TEST_IMG" 2>&1 | _filter_qemu_io | _fil $QEMU_IO -c "read -P 0 1024k 1022k" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir +echo +echo "=== Corrupted size field in compressed cluster descriptor ===" +echo +# Create an empty image and fill half of it with compressed data. +# The L2 entries of the two compressed clusters are located at +# 0x800000 and 0x800008, their original values are 0x4008000000a00000 +# and 0x4008000000a00802 (5 sectors for compressed data each). +_make_test_img 8M -o cluster_size=2M +$QEMU_IO -c "write -c -P 0x11 0 2M" -c "write -c -P 0x11 2M 2M" "$TEST_IMG" \ + 2>&1 | _filter_qemu_io | _filter_testdir + +# Reduce size of compressed data to 4 sectors: this corrupts the image. +poke_file "$TEST_IMG" $((0x800000)) "\x40\x06" +$QEMU_IO -c "read -P 0x11 0 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir + +# 'qemu-img check' however doesn't see anything wrong because it +# doesn't try to decompress the data and the refcounts are consistent. +# TODO: update qemu-img so this can be detected. +_check_test_img + +# Increase size of compressed data to the maximum (8192 sectors). +# This makes QEMU read more data (8192 sectors instead of 5, host +# addresses [0xa00000, 0xdfffff]), but the decompression algorithm +# stops once we have enough to restore the uncompressed cluster, so +# the rest of the data is ignored. +poke_file "$TEST_IMG" $((0x800000)) "\x7f\xfe" +# Do it also for the second compressed cluster (L2 entry at 0x800008). +# In this case the compressed data would span 3 host clusters +# (host addresses: [0xa00802, 0xe00801]) +poke_file "$TEST_IMG" $((0x800008)) "\x7f\xfe" + +# Here the image is too small so we're asking QEMU to read beyond the +# end of the image. +$QEMU_IO -c "read -P 0x11 0 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir +# But if we grow the image we won't be reading beyond its end anymore. +$QEMU_IO -c "write -P 0x22 4M 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir +$QEMU_IO -c "read -P 0x11 0 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir + +# The refcount data is however wrong because due to the increased size +# of the compressed data it now reaches the following host clusters. +# This can be repaired by qemu-img check by increasing the refcount of +# those clusters. +# TODO: update qemu-img to correct the compressed cluster size instead. +_check_test_img -r all +$QEMU_IO -c "read -P 0x11 0 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir +$QEMU_IO -c "read -P 0x22 4M 4M" "$TEST_IMG" 2>&1 | _filter_qemu_io | _filter_testdir + echo echo "=== Full allocation with -S 0 ===" echo diff --git a/tests/qemu-iotests/122.out b/tests/qemu-iotests/122.out index 47d8656db8..a6b7fe007e 100644 --- a/tests/qemu-iotests/122.out +++ b/tests/qemu-iotests/122.out @@ -99,6 +99,39 @@ read 1024/1024 bytes at offset 1047552 read 1046528/1046528 bytes at offset 1048576 1022 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +=== Corrupted size field in compressed cluster descriptor === + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=8388608 +wrote 2097152/2097152 bytes at offset 0 +2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 2097152/2097152 bytes at offset 2097152 +2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read failed: Input/output error +No errors were found on the image. +read 4194304/4194304 bytes at offset 0 +4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 4194304/4194304 bytes at offset 4194304 +4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read 4194304/4194304 bytes at offset 0 +4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +ERROR cluster 6 refcount=1 reference=3 +ERROR cluster 7 refcount=1 reference=2 +Repairing cluster 6 refcount=1 reference=3 +Repairing cluster 7 refcount=1 reference=2 +Repairing OFLAG_COPIED data cluster: l2_entry=8000000000c00000 refcount=3 +Repairing OFLAG_COPIED data cluster: l2_entry=8000000000e00000 refcount=2 +The following inconsistencies were found and repaired: + + 0 leaked clusters + 4 corruptions + +Double checking the fixed image now... +No errors were found on the image. +read 4194304/4194304 bytes at offset 0 +4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read 4194304/4194304 bytes at offset 4194304 +4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + === Full allocation with -S 0 === Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 -- cgit v1.2.3