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qemu/tests/qemu-iotests/284.out

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block: always fill entire LUKS header space with zeros When initializing the LUKS header the size with default encryption parameters will currently be 2068480 bytes. This is rounded up to a multiple of the cluster size, 2081792, with 64k sectors. If the end of the header is not the same as the end of the cluster we fill the extra space with zeros. This was forgetting that not even the space allocated for the header will be fully initialized, as we only write key material for the first key slot. The space left for the other 7 slots is never written to. An optimization to the ref count checking code: commit a5fff8d4b4d928311a5005efa12d0991fe3b66f9 (refs/bisect/bad) Author: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Date: Wed Feb 27 16:14:30 2019 +0300 qcow2-refcount: avoid eating RAM made the assumption that every cluster which was allocated would have at least some data written to it. This was violated by way the LUKS header is only partially written, with much space simply reserved for future use. Depending on the cluster size this problem was masked by the logic which wrote zeros between the end of the LUKS header and the end of the cluster. $ qemu-img create --object secret,id=cluster_encrypt0,data=123456 \ -f qcow2 -o cluster_size=2k,encrypt.iter-time=1,\ encrypt.format=luks,encrypt.key-secret=cluster_encrypt0 \ cluster_size_check.qcow2 100M Formatting 'cluster_size_check.qcow2', fmt=qcow2 size=104857600 encrypt.format=luks encrypt.key-secret=cluster_encrypt0 encrypt.iter-time=1 cluster_size=2048 lazy_refcounts=off refcount_bits=16 $ qemu-img check --object secret,id=cluster_encrypt0,data=redhat \ 'json:{"driver": "qcow2", "encrypt.format": "luks", \ "encrypt.key-secret": "cluster_encrypt0", \ "file.driver": "file", "file.filename": "cluster_size_check.qcow2"}' ERROR: counting reference for region exceeding the end of the file by one cluster or more: offset 0x2000 size 0x1f9000 Leaked cluster 4 refcount=1 reference=0 ...snip... Leaked cluster 130 refcount=1 reference=0 1 errors were found on the image. Data may be corrupted, or further writes to the image may corrupt it. 127 leaked clusters were found on the image. This means waste of disk space, but no harm to data. Image end offset: 268288 The problem only exists when the disk image is entirely empty. Writing data to the disk image payload will solve the problem by causing the end of the file to be extended further. The change fixes it by ensuring that the entire allocated LUKS header region is fully initialized with zeros. The qemu-img check will still fail for any pre-existing disk images created prior to this change, unless at least 1 byte of the payload is written to. Fully writing zeros to the entire LUKS header is a good idea regardless as it ensures that space has been allocated on the host filesystem (or whatever block storage backend is used). Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Message-Id: <20200207135520.2669430-1-berrange@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-02-07 16:55:20 +03:00
QA output created by 284
testing LUKS qcow2 encryption
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 encrypt.format=luks encrypt.key-secret=sec0 encrypt.iter-time=10
== cluster size 512
== checking image refcounts ==
No errors were found on the image.
== writing some data ==
wrote 1/1 bytes at offset 0
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
== writing some more data ==
wrote 1/1 bytes at offset 512
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 encrypt.format=luks encrypt.key-secret=sec0 encrypt.iter-time=10
== cluster size 2048
== checking image refcounts ==
No errors were found on the image.
== writing some data ==
wrote 1/1 bytes at offset 0
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
== writing some more data ==
wrote 1/1 bytes at offset 2048
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 encrypt.format=luks encrypt.key-secret=sec0 encrypt.iter-time=10
== cluster size 32768
== checking image refcounts ==
No errors were found on the image.
== writing some data ==
wrote 1/1 bytes at offset 0
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
== writing some more data ==
wrote 1/1 bytes at offset 32768
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== rechecking image refcounts ==
No errors were found on the image.
*** done
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