There are many existing qcow2 images that specify a backing file but
no format. This has been the source of CVEs in the past, but has
become more prominent of a problem now that libvirt has switched to
-blockdev. With older -drive, at least the probing was always done by
qemu (so the only risk of a changed format between successive boots of
a guest was if qemu was upgraded and probed differently). But with
newer -blockdev, libvirt must specify a format; if libvirt guesses raw
where the image was formatted, this results in data corruption visible
to the guest; conversely, if libvirt guesses qcow2 where qemu was
using raw, this can result in potential security holes, so modern
libvirt instead refuses to use images without explicit backing format.
The change in libvirt to reject images without explicit backing format
has pointed out that a number of tools have been far too reliant on
probing in the past. It's time to set a better example in our own
iotests of properly setting this parameter.
iotest calls to create, rebase, and convert are all impacted to some
degree. It's a bit annoying that we are inconsistent on command line
- while all of those accept -o backing_file=...,backing_fmt=..., the
shortcuts are different: create and rebase have -b and -F, while
convert has -B but no -F. (amend has no shortcuts, but the previous
patch just deprecated the use of amend to change backing chains).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200706203954.341758-9-eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The only difference is that the json:{} filename of the image looks
different. We actually do not care about that filename in this test, we
are only interested in (1) that there is a json:{} filename, and (2)
whether the backing filename can be constructed.
So just filter out the json:{} data, thus making this test pass both
with and without data_file.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20191107163708.833192-19-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Disk sizes close to INT64_MAX cause overflow, for some pretty
ridiculous output:
$ ./nbdkit -U - memory size=$((2**63 - 512)) --run 'qemu-img info $nbd'
image: nbd+unix://?socket=/tmp/nbdkitHSAzNz/socket
file format: raw
virtual size: -8388607T (9223372036854775296 bytes)
disk size: unavailable
But there's no reason to have two separate implementations of integer
to human-readable abbreviation, where one has overflow and stops at
'T', while the other avoids overflow and goes all the way to 'E'. With
this patch, the output now claims 8EiB instead of -8388607T, which
really is the correct rounding of largest file size supported by qemu
(we could go 511 bytes larger if we used byte-accurate sizing instead
of rounding up to the next sector boundary, but that wouldn't change
the human-readable result).
Quite a few iotests need updates to expected output to match.
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Max Reitz <mreitz@redhat.com>
Instead of having every block driver which implements
bdrv_refresh_filename() copy all of the strong runtime options over to
bs->full_open_options, implement this process generically in
bdrv_refresh_filename().
This patch only adds this new generic implementation, it does not remove
the old functionality. This is done in a follow-up patch.
With this patch, some superfluous information (that should never have
been there) may be removed from some JSON filenames, as can be seen in
the change to iotests 110's and 228's reference outputs.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190201192935.18394-24-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Test 110 tests relative backing filenames for complex BDS trees. Now
that the originally supposedly failing test passes, let us add a new
failing test: Quorum can never work automatically (without detecting
whether all child nodes have the same base directory, but that would be
rather inconsistent behavior).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-21-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
bdrv_get_full_backing_filename_from_filename() breaks down when it comes
to JSON filenames. Using bdrv_dirname() as the basis is better because
since we have BDS, we can descend through the BDS tree to the protocol
layer, which gives us a greater probability of finding a non-JSON name;
also, bdrv_dirname() is more correct as it allows block drivers to
override the generation of that directory name in a protocol-specific
way.
We still need to keep bdrv_get_full_backing_filename_from_filename(),
though, because it has valid callers which need it during image creation
when no BDS is available yet.
This makes a test case in qemu-iotest 110, which was supposed to fail,
work. That is actually good, but we need to change the reference output
(and the comment in 110) accordingly.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-20-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
For more complex BDS trees that can be created under normal circumstances,
we lose the ability to issue query commands because of our inability to
re-construct the absolute filename.
Instead, omit this field when it is a problem and present as much information
as we can.
This will change the expected output in iotest 110, where we will now see a
json filename and the lack of an absolute filename instead of an error.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1450122916-4706-6-git-send-email-jsnow@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This will let us print options in a format that the user would actually
write it on the command line (foo=bar,baz=asd,etc=def), without
prepending a spurious comma at the beginning of the list, or quoting
values unnecessarily. This patch provides the following changes:
* write and id=, if the option has an id
* do not print separator before the first element
* do not quote string arguments
* properly escape commas (,) for QEMU
Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Sometimes, qemu does not have a filename to work with, so it does not
know which directory to use for a backing file specified by a relative
filename. Add a test which tests that qemu exits with an appropriate
error message.
Additionally, add a test for qemu-img create with a backing filename
relative to the backed image's base directory while omitting the image
size.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Eric Blake
Max Reitz
John Snow
Kővágó, Zoltán