2020-12-02 17:43:52

by Borislav Petkov

Subject: Re: [PATCH] x86/sgx: Initialize "ret" in sgx_ioc_enclave_add_pages()

On Wed, Dec 02, 2020 at 06:22:00PM +0200, Jarkko Sakkinen wrote:
> Initialize "ret" to zero as otherwise a zero length address range will
> leave it uninitialized.

That length is:

* @length: length of the data (multiple of the page size)

I think we wanna fail this even earlier when it wants to add data of
length 0 because that sounds nonsensical to me. Or is there some use
case for zero-length data?

Btw, pls CC lkml on patch submissions.

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette

2020-12-03 18:28:33

by Jarkko Sakkinen

Subject: Re: [PATCH] x86/sgx: Initialize "ret" in sgx_ioc_enclave_add_pages()

On Wed, Dec 02, 2020 at 06:38:29PM +0100, Borislav Petkov wrote:
> On Wed, Dec 02, 2020 at 06:22:00PM +0200, Jarkko Sakkinen wrote:
> > Initialize "ret" to zero as otherwise a zero length address range will
> > leave it uninitialized.
>
> That length is:
>
> * @length: length of the data (multiple of the page size)
>
> I think we wanna fail this even earlier when it wants to add data of
> length 0 because that sounds nonsensical to me. Or is there some use
> case for zero-length data?
>
> Btw, pls CC lkml on patch submissions.

Yeah, makes sense to fail right after copying the parameter struct
with -EINVAL.

> Thx.
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette
>

/Jarkko