[2/3] bpf: Remove dead variable

task is never used in bpf_get_current_uid_gid(), kill it.

Signed-off-by: Richard Weinberger <richard@nod.at>
---
 kernel/bpf/helpers.c | 1 -
 1 file changed, 1 deletion(-)

On 10/16/2017 08:18 PM, Richard Weinberger wrote:
> task is never used in bpf_get_current_uid_gid(), kill it.
>
> Signed-off-by: Richard Weinberger <richard@nod.at>
> ---
>   kernel/bpf/helpers.c | 1 -
>   1 file changed, 1 deletion(-)
>
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index e8845adcd15e..511c9d522cfc 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -131,7 +131,6 @@ const struct bpf_func_proto bpf_get_current_pid_tgid_proto = {
>
>   BPF_CALL_0(bpf_get_current_uid_gid)
>   {
> -	struct task_struct *task = current;
>   	kuid_t uid;
>   	kgid_t gid;
>
>

Needs to be squashed into patch 1/3?

Am Montag, 16. Oktober 2017, 20:54:36 CEST schrieb Daniel Borkmann:
> On 10/16/2017 08:18 PM, Richard Weinberger wrote:
> > task is never used in bpf_get_current_uid_gid(), kill it.
> > 
> > Signed-off-by: Richard Weinberger <richard@nod.at>
> > ---
> > 
> >   kernel/bpf/helpers.c | 1 -
> >   1 file changed, 1 deletion(-)
> > 
> > diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> > index e8845adcd15e..511c9d522cfc 100644
> > --- a/kernel/bpf/helpers.c
> > +++ b/kernel/bpf/helpers.c
> > @@ -131,7 +131,6 @@ const struct bpf_func_proto
> > bpf_get_current_pid_tgid_proto = {> 
> >   BPF_CALL_0(bpf_get_current_uid_gid)
> >   {
> > 
> > -	struct task_struct *task = current;
> > 
> >   	kuid_t uid;
> >   	kgid_t gid;
> 
> Needs to be squashed into patch 1/3?

I can squash it into 1/3, I kept it that way because
even without 1/3 this variable is unused.

Thanks,
//richard

On 10/16/2017 08:59 PM, Richard Weinberger wrote:
> Am Montag, 16. Oktober 2017, 20:54:36 CEST schrieb Daniel Borkmann:
>> On 10/16/2017 08:18 PM, Richard Weinberger wrote:
>>> task is never used in bpf_get_current_uid_gid(), kill it.
>>>
>>> Signed-off-by: Richard Weinberger <richard@nod.at>
>>> ---
>>>
>>>    kernel/bpf/helpers.c | 1 -
>>>    1 file changed, 1 deletion(-)
>>>
>>> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
>>> index e8845adcd15e..511c9d522cfc 100644
>>> --- a/kernel/bpf/helpers.c
>>> +++ b/kernel/bpf/helpers.c
>>> @@ -131,7 +131,6 @@ const struct bpf_func_proto
>>> bpf_get_current_pid_tgid_proto = {>
>>>    BPF_CALL_0(bpf_get_current_uid_gid)
>>>    {
>>>
>>> -	struct task_struct *task = current;
>>>
>>>    	kuid_t uid;
>>>    	kgid_t gid;
>>
>> Needs to be squashed into patch 1/3?
>
> I can squash it into 1/3, I kept it that way because
> even without 1/3 this variable is unused.

Hmm, the helper looks like the below. In patch 1/3 you removed
the 'if (unlikely(!task))' test where the variable was used before,
so 2/3 without the 1/3 would result in a compile error.

BPF_CALL_0(bpf_get_current_uid_gid)
{
	struct task_struct *task = current;
	kuid_t uid;
	kgid_t gid;

	if (unlikely(!task))
		return -EINVAL;

	current_uid_gid(&uid, &gid);
	return (u64) from_kgid(&init_user_ns, gid) << 32 |
		     from_kuid(&init_user_ns, uid);
}

Am Montag, 16. Oktober 2017, 21:11:47 CEST schrieb Daniel Borkmann: 
> > I can squash it into 1/3, I kept it that way because
> > even without 1/3 this variable is unused.
> 
> Hmm, the helper looks like the below. In patch 1/3 you removed
> the 'if (unlikely(!task))' test where the variable was used before,
> so 2/3 without the 1/3 would result in a compile error.

Why a compile error? It emits a warning.

> BPF_CALL_0(bpf_get_current_uid_gid)
> {
> 	struct task_struct *task = current;
> 	kuid_t uid;
> 	kgid_t gid;
> 
> 	if (unlikely(!task))
> 		return -EINVAL;

Well, this is the only "user". Okay.

> 	current_uid_gid(&uid, &gid);

Here we use current. So, task was always in vain.

So, I can happily squash 2/3 into 1/3 and resent.
The series just represented the way I've worked on the code... 

Thanks,
//richard

On 10/16/2017 09:22 PM, Richard Weinberger wrote:
[...]
> So, I can happily squash 2/3 into 1/3 and resent.

Yeah, please just squash them.

Thanks,
Daniel