Re: [PATCH v2] KEYS: Protect pkey method checks against type removal

[Yuansheng Yang]

On Thu, Nov 05, 2026 at 01:59:19AM +0200, Jarkko Sakkinen wrote:
> Please respond to any questions *before* sending a follow-up patch by
> properly using email client and quoting etc.

Sorry. I'll answer the review before sending another revision.

> > +	if (!params->key->type->asym_query) {
> 		ret -EOPNOTSUPP;

I'll move the assignment inside the if block, here and in the other
method checks.

> There should be an empty line prepending the label.

Will fix throughout.

> >  	if (copy_to_user(_res, &res, sizeof(res)) == 0 &&
> >  	    clear_user(_res->__spare, sizeof(_res->__spare)) == 0)
> >  		ret = 0;
>
> Why up_read is not here?

To avoid holding key->sem across user memory faults. After asym_query(),
res is a local copy. Copying it out no longer needs the lock.

> Please figure this part out it does not do a great job minimizing the diff.
>
> There were similar repeating issues that I did not specifically point
> out.

Agreed. I'll keep the switch, allocations and error handling in place.
I'll move the method checks next to the callbacks under key->sem and use
shared unlock points. I'll check the other paths for the same issues.

Thanks,
Yuansheng Yang