On 11.10.2016 14:09, Vladimir Sementsov-Ogievskiy wrote:
> On 01.10.2016 17:46, Max Reitz wrote:
>> On 30.09.2016 12:53, Vladimir Sementsov-Ogievskiy wrote:
>>> Add dirty bitmap extension as specified in docs/specs/qcow2.txt.
>>> For now, just mirror extension header into Qcow2 state and check
>>> constraints.
>>>
>>> For now, disable image resize if it has bitmaps. It will be fixed later.
>>>
>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>>> ---
>>>   block/qcow2.c | 83
>>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>   block/qcow2.h |  4 +++
>>>   2 files changed, 87 insertions(+)
>>>
>>> diff --git a/block/qcow2.c b/block/qcow2.c
>>> index c079aa8..08c4ef9 100644
>>> --- a/block/qcow2.c
>>> +++ b/block/qcow2.c
>> [...]
>>
>>> @@ -162,6 +164,62 @@ static int
>>> qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
>>>               }
>>>               break;
>>>   +        case QCOW2_EXT_MAGIC_DIRTY_BITMAPS:
>>> +            ret = bdrv_pread(bs->file, offset, &bitmaps_ext, ext.len);
>> Overflows with ext.len > sizeof(bitmaps_ext).
>>
>> (ext.len < sizeof(bitmaps_ext) is also wrong, but less dramatically so.)
>>
>>> +            if (ret < 0) {
>>> +                error_setg_errno(errp, -ret, "ERROR: bitmaps_ext: "
>>> +                                 "Could not read ext header");
>>> +                return ret;
>>> +            }
>>> +
>>> +            if (bitmaps_ext.reserved32 != 0) {
>>> +                error_setg_errno(errp, -ret, "ERROR: bitmaps_ext: "
>>> +                                 "Reserved field is not zero.");
>> Please drop the full stop at the end.
> 
> what do you mean? goto to fail: here? or not stop at all, just print error?

The "." at the end of the message. :-)

(https://en.wikipedia.org/wiki/Full_stop)

Max