The null-co driver doesn't zeroize buffer in its default config,
because it is designed for testing and tests want to run fast.
However this confuses security researchers (access to uninit
buffers).
A one-line patch supposed which became a painful one, because
there is so many different syntax to express the same usage:
opt = qdict_new();
qdict_put_str(opt, "read-zeroes", "off");
null_bs = bdrv_open("null-co://", NULL, opt, BDRV_O_RDWR | BDRV_O_PROTOCOL,
&error_abort);
vm.qmp('blockdev-add', driver='null-co', read_zeroes=False, ...)
vm.add_drive_raw("id=drive0,driver=null-co,read-zeroes=off,if=none")
blk0 = { 'node-name': 'src',
'driver': 'null-co',
'read-zeroes': 'off' }
'file': {
'driver': 'null-co',
'read-zeroes': False,
}
"file": {
"driver": "null-co",
"read-zeroes": "off"
}
{ "execute": "blockdev-add",
"arguments": {
"driver": "null-co",
"read-zeroes": false,
"node-name": "disk0"
}
}
opts = {'driver': 'null-co,read-zeroes=off', 'node-name': 'root', 'size': 1024}
qemu -drive driver=null-co,read-zeroes=off
qemu-io ... "json:{'driver': 'null-co', 'read-zeroes': false, 'size': 65536}"
qemu-img null-co://,read-zeroes=off
qemu-img ... -o
data_file="json:{'driver':'null-co',,'read-zeroes':false,,'size':'4294967296'}"
There are probably more.
Anyhow, the iotests I am not sure and should be audited are 056, 155
(I don't understand the syntax) and 162.
Please review,
Phil.
Philippe Mathieu-Daud=C3=A9 (2):
block: Explicit null-co uses 'read-zeroes=3Dfalse'
block/null: Enable 'read-zeroes' mode by default
docs/devel/testing.rst | 14 +++++++-------
tests/qtest/fuzz/generic_fuzz_configs.h | 11 ++++++-----
block/null.c | 2 +-
tests/test-bdrv-drain.c | 10 ++++++++--
tests/acceptance/virtio_check_params.py | 2 +-
tests/perf/block/qcow2/convert-blockstatus | 6 +++---
tests/qemu-iotests/040 | 2 +-
tests/qemu-iotests/041 | 12 ++++++++----
tests/qemu-iotests/051 | 2 +-
tests/qemu-iotests/051.out | 2 +-
tests/qemu-iotests/051.pc.out | 4 ++--
tests/qemu-iotests/087 | 6 ++++--
tests/qemu-iotests/118 | 2 +-
tests/qemu-iotests/133 | 2 +-
tests/qemu-iotests/153 | 8 ++++----
tests/qemu-iotests/184 | 2 ++
tests/qemu-iotests/184.out | 10 +++++-----
tests/qemu-iotests/218 | 3 +++
tests/qemu-iotests/224 | 3 ++-
tests/qemu-iotests/224.out | 8 ++++----
tests/qemu-iotests/225 | 2 +-
tests/qemu-iotests/227 | 4 ++--
tests/qemu-iotests/227.out | 4 ++--
tests/qemu-iotests/228 | 2 +-
tests/qemu-iotests/235 | 1 +
tests/qemu-iotests/245 | 2 +-
tests/qemu-iotests/270 | 2 +-
tests/qemu-iotests/283 | 3 ++-
tests/qemu-iotests/283.out | 4 ++--
tests/qemu-iotests/299 | 1 +
tests/qemu-iotests/299.out | 2 +-
tests/qemu-iotests/300 | 4 ++--
32 files changed, 82 insertions(+), 60 deletions(-)
--=20
2.26.2
