Re: [PATCH v4 3/3] binder: use euid from cred instead of using task

On Fri, Oct 8, 2021 at 5:25 PM Casey Schaufler [off-list ref] wrote:

On 10/8/2021 2:12 PM, Paul Moore wrote:

quoted

On Wed, Oct 6, 2021 at 8:46 PM Todd Kjos [off-list ref] wrote:

quoted

Set a transaction's sender_euid from the 'struct cred'
saved at binder_open() instead of looking up the euid
from the binder proc's 'struct task'. This ensures
the euid is associated with the security context that
of the task that opened binder.

Fixes: 457b9a6f09f0 ("Staging: android: add binder driver")
Signed-off-by: Todd Kjos <redacted>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Cc: stable@vger.kernel.org # 4.4+
---
v3: added this patch to series

 drivers/android/binder.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

This is an interesting ordering of the patches.  Unless I'm missing
something I would have expected patch 3/3 to come first, followed by
2/3, with patch 1/3 at the end; basically the reverse of what was
posted here.

My reading of the previous thread was that Casey has made his peace
with these changes

Yes. I will address the stacking concerns more directly.
I am still somewhat baffled by the intent of the hook, the data
passed to it, and the SELinux policy enforcement decisions, but
that's beyond my scope.

Okay, I just wanted to make sure there were no objections.

-- 
paul moore
www.paul-moore.com