Re: [PULL v2 05/13] accel/tcg: Relax va restrictions on 64-bit guests

[Richard Henderson]

On 6/5/20 10:46 AM, Alex Bennée wrote:
> 
> Richard Henderson <rth@twiddle.net> writes:
> 
>> On 6/5/20 7:11 AM, Alex Bennée wrote:
>>> @@ -467,7 +467,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, 
>>> int prot,
>>>           * It can fail only on 64-bit host with 32-bit target.
>>>           * On any other target/host host mmap() handles this error 
>>> correctly.
>>>           */
>>> -        if (!guest_range_valid(start, len)) {
>>> +        if (end < start || !guest_range_valid(start, len)) {
>>>              errno = ENOMEM;
>>>              goto fail;
>>>          }
>>
>> Interesting.  I was adjusting guest_range_valid tagged pointers yesterday, 
>> and
>> thought that it looked buggy.
> 
> Should be picking this up in guest_range_valid?

I think so.  How can a range really be considered valid if it wraps?


r~