Re: [PATCH 32/32] selftests/namespaces: add file handle selftests

On Thu, Sep 11, 2025 at 11:15 AM Christian Brauner [off-list ref] wrote:

On Wed, Sep 10, 2025 at 07:30:03PM +0200, Amir Goldstein wrote:

quoted

On Wed, Sep 10, 2025 at 4:40 PM Christian Brauner [off-list ref] wrote:

quoted

Add a bunch of selftests for namespace file handles.

Signed-off-by: Christian Brauner <brauner@kernel.org>

Obviously, I did not go over every single line, but for the general
test template and test coverage you may add:

Reviewed-by: Amir Goldstein <amir73il@gmail.com>

However, see my comment on file handle support patch.
The test matrix is incomplete.

I mean, I'll just drop to non-root in the non-cross ns tests:

/* Drop to unprivileged uid/gid */
ASSERT_EQ(setresgid(65534, 65534, 65534), 0); /* nogroup */
ASSERT_EQ(setresuid(65534, 65534, 65534), 0); /* nobody */

That would be good I think.

quoted

Maybe it would be complete if test is run as root and then
as non root, but then I think the test needs some changes
for running as root and opening non-self ns.

I am not sure what the standard is wrt running the selftests
as root /non-root.

I see that the userns isolation tests do:
/* Map current uid/gid to root in the new namespace */

Are you assuming that non root is running this test
or am I missing something?

No, I'm not assuming that. I just need a new user namespace and become
root in it to assume privilege over it so I can test that decoding
doesn't work from an ancestor userns owned namespace.

With dropping to unprivileged uid/gid in parent, I understand it should work.
I guess I wasn't sure if dropping to unprivileged uid/gid was required for the
test to pass when the test is run as root user, but with the addition of
dropping to unprivileged uid/gid - feel free to add:

Reviewed-by: Amir Goldstein <amir73il@gmail.com>


Thanks,
Amir.