Re: [Qemu-devel] [PATCH v1 5/9] test-string-input-visitor: add more tests

[David Hildenbrand]

On 15.11.18 18:13, Eric Blake wrote:
> On 11/15/18 8:04 AM, David Hildenbrand wrote:
>> Test that very big/small values are not accepted and that ranges with
>> only one element work.
>>
>> Rename expect4 to expect5, as we will be moving that to a separate ulist
>> test after the rework.
>>
>> Signed-off-by: David Hildenbrand <address@hidden>
>> ---
>>   tests/test-string-input-visitor.c | 22 ++++++++++++++++++++--
>>   1 file changed, 20 insertions(+), 2 deletions(-)
>>
> 
> I don't see a test for a range that wraps around (such as UINT_MAX-0); 
> that's worth testing (whether it happens to work or is rejected as 
> invalid).  Do we require ranges to be ascending, or does 6-5 result in 
> the sequence 5, 6?  I also recall that our range code imposes a limit on 
> the maximum elements present in a single range, in order to prevent 
> denial-of-service attacks where a caller could request 0-INT_MAX to 
> exhaust resources enumerating everything in the range; does our 
> testsuite cover those limits?
>
Ranges have to be ascending and old code enforced that. New code still
enforces it. Wrapping ranges are AFAIC also not supported - not
ascending. I can add a test.

The limit is a good point. It is neither in the tests nor in the new
code. But now we finally have an explanation on the 65000-somewhat
thingy. I assume that we need such a limit?

-- 

Thanks,

David / dhildenb