Re: [PATCH 3/8] ucounts: Fix and simplify RLIMIT_NPROC handling during setuid()+execve

On Mon, Feb 14, 2022 at 09:10:49AM -0600, "Eric W. Biederman" ebiederm@xmission.com wrote:

I really like how cleanly this patch seems to be. Unfortunately it is wrong.

It seems [1] so:

setuid() // RLIMIT_NPROC is fine at this moment ... fork() ... ... fork() execve() // eh, oh

This "punishes" the exec'ing task although the cause is elsewhere.

Michal

[1] The decoupled setuid()+execve() check can be interpretted both ways. I understood historically the excess at the setuid() moment is relevant.