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>
It is interesting to know whether the shutdown cause was 'quit' or
'reset', especially when using "--no-reboot". In that case, a management
layer can now determine if the guest wanted a reboot or shutdown, and
can act accordingly.
Changes the output of the reason in the iotests from 'host-qmp' to
'host-qmp-quit'. This does not break compatibility because
the field was introduced in the same version.
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Message-Id: <20181205110131.23049-4-d.csapak@proxmox.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This makes it possible to determine what the exact reason was for
a RESET or a SHUTDOWN. A management layer might need the specific reason
of those events to determine which cleanups or other actions it needs to do.
This patch also updates the iotests to the new expected output that includes
the reason.
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Message-Id: <20181205110131.23049-3-d.csapak@proxmox.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The contents of a qcow2 bitmap are rounded up to a size that
matches the number of bits available for the granularity, but
that granularity differs for 32-bit hosts (our default 64k
cluster allows for 2M bitmap coverage per 'long') and 64-bit
hosts (4M bitmap per 'long'). If the image is a multiple of
2M but not 4M, then the number of bytes occupied by the array
of longs in memory differs between architecture, thus
resulting in different SHA256 hashes.
Furthermore (but untested by me), if our computation of the
SHA256 hash is at all endian-dependent because of how we store
data in memory, that's another variable we'd have to account
for (ideally, we specified the bitmap stored in qcow2 as
fixed-endian on disk, because the same qcow2 file must be
usable across any architecture; but that says nothing about
how we represent things in memory). But we already have test
165 to validate that bitmaps are stored correctly on disk,
while this test is merely testing that the bitmap exists.
So for this test, the easiest solution is to filter out the
actual hash value. Broken in commit 4096974e.
Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20171117190422.23626-1-eblake@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If an image contains persistent bitmaps, we cannot use the
fast path of bdrv_make_empty() to clear the image during
qemu-img commit, because that will lose the clusters related
to the bitmaps.
Also leave a comment in qcow2_read_extensions to remind future
feature additions to think about fast-path removal, since we
just barely fixed the same bug for LUKS encryption.
It's a pain that qemu-img has not yet been taught to manipulate,
or even at a very minimum display, information about persistent
bitmaps; instead, we have to use QMP commands. It's also a
pain that only qeury-block and x-debug-block-dirty-bitmap-sha256
will allow bitmap introspection; but the former requires the
node to be hooked to a block device, and the latter is experimental.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tweak 097 and 176 to operate on an image that is not cluster-aligned,
to give further coverage of clearing out an entire image, including
the recent fix to eliminate the difference between fast path (97) and
slow (176) for qcow2. Also tested on qcow (97 only, since qcow lacks
snapshots).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331185356.2479-4-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The previous commit:
commit a3e1505dae
Author: Eric Blake <eblake@redhat.com>
Date: Mon Dec 5 09:49:34 2016 -0600
qcow2: Don't strand clusters near 2G intervals during commit
extended the 097 test case so that it did two passes, once
with an internal snapshot, once without.
qcow (v1) does not support internal snapshots, so this change
broke test 097 when run against qcow.
This splits 097 in two, creating a new 176 that tests the
internal snapshot codepath, effectively putting 097 back
to its content before the above commit.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20170221115512.21918-8-berrange@redhat.com>
[eblake: test collisions: s/173/176/g]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331185356.2479-2-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
