Re: [PATCH v17 18/23] platform/x86: Intel SGX driver

[Dave Hansen]

On 12/17/18 10:01 AM, Jarkko Sakkinen wrote:
>>> +	encl->mm = current->mm;  <---------------------------------> +	encl->base = secs->base;
>>> +	encl->size = secs->size;
>>> +	encl->ssaframesize = secs->ssa_frame_size;
>>> +	encl->backing = backing;
>>> +
>>> +	return encl;
>>> +}
>> How is this OK without taking a reference on the mm?
>>
>> I have a feeling a bunch of your bugs with the mmu notifiers and so
>> forth are because the refcounting is wrong here.
>>
>> Sean's SGX_ENCL_MM_RELEASED would, I think be unnecessary if you just
>> take a refcount here and release it when the enclave is destroyed.
> Right, atomic_inc(encl->mm->count) here and once when releasing.
> 
> The we would not even need the whole mmu notifier in the first place.

Please use mmget()/mmput().