Re: [GIT PULL] exit cleanups for v5.16

From: Eric W. Biederman
Date: Wed Nov 10 2021 - 13:14:53 EST


ebiederm@xxxxxxxxxxxx (Eric W. Biederman) writes:

> Linus,
>
> Please pull the exit-cleanups-for-v5.16 branch from the git tree:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git exit-cleanups-for-v5.16
>
> HEAD: f91140e4553408cacd326624cd50fc367725e04a Arnd Bergmann <arnd@xxxxxxxx>
>
>
> While looking at some issues related to the exit path in the kernel I
> found several instances where the code is not using the existing
> abstractions properly.
>
> This set of changes introduces force_fatal_sig a way of sending
> a signal and not allowing it to be caught, and corrects the
> misuse of the existing abstractions that I found.
>
> A lot of the misuse of the existing abstractions are silly things such
> as doing something after calling a no return function, rolling BUG by
> hand, doing more work than necessary to terminate a kernel thread, or
> calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL).
>
> In the review a deficiency in force_fatal_sig and force_sig_seccomp
> where ptrace or sigaction could prevent the delivery of the signal was
> found. I have added a change that adds SA_IMMUTABLE to change that
> makes it impossible to interrupt the delivery of those signals, and
> allows backporting to fix force_sig_seccomp.
>
> Arnd found an issue where a function passed to kthread_run had the wrong
> prototype, and after my cleanup was failing to build.

I forgot to mention there is a minor conflict with the staging tree.
One of the functions that I cleaned up was in a file that was completely
removed from staging. The result is that when you encounter the
conflict that file can simply be removed.

Eric