Re: [RFC PATCH] audit: use current whenever possible
On Mon, Jul 23, 2018 at 3:40 PM Richard Guy Briggs <rgb(a)redhat.com> wrote:
On 2018-07-20 18:17, Paul Moore wrote:
> There are many places, notably audit_log_task_info() and
> audit_log_exit(), that take task_struct pointers but in reality they
> are always working on the current task. This patch eliminates the
> task_struct arguments and uses current directly which allows a number
> of cleanups as well.
I came across and removed a several in the audit task struct cleanup,
but it looks like you've rebased over those and caught a few more.
I just based this patch against audit/next to make life easier. Since
the earliest it would possibly go into the audit tree would be after
the next merge window it will likely get rebased/merged again. If
there is another patch that does some of this work and gets merged
first, awesome, if not, that's fine too.
I'm fine with delaying setting task's context to NULL for
__audit_free().
Yeah, it really shouldn't matter when it happens in __audit_free() as
we should be the only ones who are touching that task_struct at that
point in time.
Why was the context originally taken for __audit_syscall_exit() and
given back once the syscall event records have been issued? Is there a
possible race with something else?
That was a bit bizarre, wasn't it? There shouldn't be a race
condition as the audit_context is private to the individual task and
at the point in time where __audit_syscall_exit() is being called we
shouldn't have to worry about other things hitting the task_struct.
If anything, this patch should actually make things better by not
setting the current->context to NULL at the start of
__audit_syscall_exit() only to reset it back to the original value at
the end (the audit_take_context() function, and it's relationship with
audit_log_exit() was ... odd ... and that is me being kind).
I'm chalking this up to "audit being audit" :/
> Signed-off-by: Paul Moore <paul(a)paul-moore.com>
Otherwise, this cleanup looks like a good simplification.
Reviewed-by: Richard Guy Briggs <rgb(a)redhat.com>
Diffstats that remove more lines than they add always make me happy.
Thanks for taking a look. It boots and passes our tests but I still
haven't convinced myself all those changes are correct. I'll send a
note if/when it gets merged, but like I said that won't happen until
after the merge window closes as we are at -rc6 right now.
--
paul moore
www.paul-moore.com