Re: [PATCH 1/8] ucounts: Fix RLIMIT_NPROC regression

[Michal Koutný]

On Thu, Feb 10, 2022 at 08:13:17PM -0600, "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> wrote:
> This can be fixed either by fixing the test or by moving the increment
> to be before the test.  Fix it my moving copy_creds which contains
> the increment before is_ucounts_overlimit.

This is simpler than my approach and I find it correct too.

> Both the test in fork and the test in set_user were semantically
> changed when the code moved to ucounts.  The change of the test in
> fork was bad because it was before the increment.
>
> The test in set_user was wrong and the change to ucounts fixed it.  So
> this fix is only restore the old behavior in one lcatio not two.

Whom should be the task accounted to in the case of set*uid? (The change
to ucounts made the check against the pre-switch user's ucounts.)

> ---
>  kernel/fork.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

Reviewed-by: Michal Koutný <mkoutny@xxxxxxxx>