Re: [PATCH] selftests: capabilities: namespace create varies for root and normal user

From: swarup <swarupkotikalapudi@gmail.com>
To: Shuah Khan <skhan@linuxfoundation.org>
Cc: shuah@kernel.org, linux-kselftest@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-kernel-mentees@lists.linuxfoundation.org
Subject: Re: [PATCH] selftests: capabilities: namespace create varies for root and normal user
Date: Sat, 11 Nov 2023 22:23:38 +0530	[thread overview]
Message-ID: <ZU+xkpH09xjzO5IS@swarup-virtual-machine> (raw)
In-Reply-To: <0f3a63ff-cbf9-4e06-8f4f-fd22bafa26fe@linuxfoundation.org>

On Tue, Nov 07, 2023 at 02:23:34PM -0700, Shuah Khan wrote:
> On 9/29/23 06:53, Swarup Laxman Kotiaklapudi wrote:
> > Change namespace creation for root and non-root
> > user differently in create_and_enter_ns() function
> > 
> 
> Sorry for the delay on reviewing this.
> 
> Can you tell me more about why this change is needed and
> include it in the change log.
> 
> thanks,
> -- Shuah

Hi Shuah,

This patchset was raised to fix below TODO:

"If we're already root, we could skip creating the userns."

Without this patchset, function create_and_enter_ns(),
at this path --> tools/testing/selftests/capabilities/test_execve.c
was as mentioned below:

static bool create_and_enter_ns(uid_t inner_uid)
{
   ....
   if (unshare(CLONE_NEWNS) == 0) {
       ....   
    } else if (unshare(CLONE_NEWUSER | CLONE_NEWNS) == 0) {
       ....
     } else {
                ksft_exit_skip("must be root or be able to create a userns\n");
     }

     ...
}

To fix the TODO, above mentioned if block is executed if root user,
for normal user it enters inside 'else if' block.

Thanks,
Swarup