Re: [Qemu-devel] [for 3.1? PATCH] qcow2: Assert that refcount block offsets fit in the refcount table

[Alberto Garcia]

On Tue 13 Nov 2018 06:06:54 PM CET, Eric Blake <address@hidden> wrote:

>> Refcount table entries have a field to store the offset of the
>> refcount block. The rest of the bits of the entry are currently
>> reserved.
>> 
>> The offset is always taken from the entry using REFT_OFFSET_MASK to
>> ensure that we only use the bits that belong to that field.
>> 
>> While that mask is used every time we read from the refcount table, it
>> is never used when we write to it. Due to the other constraints of the
>> qcow2 format QEMU can never produce refcount block offsets that don't
>> fit in that field so any such offset when allocating a refcount block
>> would indicate a bug in QEMU.
>> ---
>>   block/qcow2-refcount.c | 3 +++
>>   1 file changed, 3 insertions(+)
>> 
>
> Reviewed-by: Eric Blake <address@hidden>

Yes, for 3.1, shall I resend it with the updated subject message?

Berto