In most cases, _make_test_img does not need a _filter_imgfmt on top. It
does that by itself.
(The exception is when IMGFMT has been overwritten but TEST_IMG has not.
In such cases, we do need a _filter_imgfmt on top to filter the test's
original IMGFMT from TEST_IMG.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201027190600.192171-8-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
Just rm will not delete external data files. Use _rm_test_img every
time we delete a test image.
(In the process, clean up the indentation of every _cleanup() this patch
touches.)
((Also, use quotes consistently. I am happy to see unquoted instances
like "rm -rf $TEST_DIR/..." go.))
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20191107163708.833192-16-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Bash is not always installed as /bin/bash. In particular on OpenBSD,
the package installs it in /usr/local/bin.
Use the 'env' shebang to search bash in the $PATH.
Patch created mechanically by running:
$ git grep -lE '#! ?/bin/bash' -- tests/qemu-iotests \
| while read f; do \
sed -i 's|^#!.\?/bin/bash$|#!/usr/bin/env bash|' $f; \
done
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The previous patch fixed the inherits_from pointer after block-stream,
and this one does the same for block-commit.
When block-commit finishes and the 'top' node is not the topmost one
from the backing chain then all nodes above 'base' up to and including
'top' are removed from the chain.
The bdrv_drop_intermediate() call converts a chain like this one:
base <- intermediate <- top <- active
into this one:
base <- active
In a simple scenario each backing file from the first chain has the
inherits_from attribute pointing to its parent. This means that
reopening 'active' will recursively reopen all its children, whose
options can be changed in the process.
However after the 'block-commit' call base.inherits_from is NULL and
the chain is broken, so 'base' does not inherit from 'active' and will
not be reopened automatically:
$ qemu-img create -f qcow2 hd0.qcow2 1M
$ qemu-img create -f qcow2 -b hd0.qcow2 hd1.qcow2
$ qemu-img create -f qcow2 -b hd1.qcow2 hd2.qcow2
$ $QEMU -drive if=none,file=hd2.qcow2
{ 'execute': 'block-commit',
'arguments': {
'device': 'none0',
'top': 'hd1.qcow2' } }
{ 'execute': 'human-monitor-command',
'arguments': {
'command-line':
'qemu-io none0 "reopen -o backing.l2-cache-size=2M"' } }
{ "return": "Cannot change the option 'backing.l2-cache-size'\r\n"}
This patch updates base.inherits_from in this scenario, and adds a
test case.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When a BlockDriverState's child is opened (be it a backing file, the
protocol layer, or any other) inherits_from is set to point to the
parent node. Children opened separately and then attached to a parent
don't have this pointer set.
bdrv_reopen_queue_child() uses this to determine whether a node's
children must also be reopened inheriting the options from the parent
or not. If inherits_from points to the parent then the child is
reopened and its options can be changed, like in this example:
$ qemu-img create -f qcow2 hd0.qcow2 1M
$ qemu-img create -f qcow2 hd1.qcow2 1M
$ $QEMU -drive if=none,node-name=hd0,file=hd0.qcow2,\
backing.driver=qcow2,backing.file.filename=hd1.qcow2
(qemu) qemu-io hd0 "reopen -o backing.l2-cache-size=2M"
If the child does not inherit from the parent then it does not get
reopened and its options cannot be changed:
$ $QEMU -drive if=none,node-name=hd1,file=hd1.qcow2
-drive if=none,node-name=hd0,file=hd0.qcow2,backing=hd1
(qemu) qemu-io hd0 "reopen -o backing.l2-cache-size=2M"
Cannot change the option 'backing.l2-cache-size'
If a disk image has a chain of backing files then all of them are also
connected through their inherits_from pointers (i.e. it's possible to
walk the chain in reverse order from base to top).
However this is broken if the intermediate nodes are removed using
e.g. block-stream because the inherits_from pointer from the base node
becomes NULL:
$ qemu-img create -f qcow2 hd0.qcow2 1M
$ qemu-img create -f qcow2 -b hd0.qcow2 hd1.qcow2
$ qemu-img create -f qcow2 -b hd1.qcow2 hd2.qcow2
$ $QEMU -drive if=none,file=hd2.qcow2
(qemu) qemu-io none0 "reopen -o backing.l2-cache-size=2M"
(qemu) block_stream none0 0 hd0.qcow2
(qemu) qemu-io none0 "reopen -o backing.l2-cache-size=2M"
Cannot change the option 'backing.l2-cache-size'
This patch updates the inherits_from pointer if the intermediate nodes
of a backing chain are removed using bdrv_set_backing_hd(), and adds a
test case for this scenario.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>