Re: [PATCH v2 4/5] exec: Move exec_mmap right after de_thread in flush_old_exec

Bernd Edlinger
2020-03-09T19:35:04Z

On 3/8/20 10:38 PM, Eric W. Biederman wrote:
>
> I have read through the code in exec_mmap and I do not see anything
> that depends on sighand or the sighand lock, or on signals in anyway
> so this should be safe.
>
> This rearrangement of code has two siginficant benefits. It makes
^ typo: significant

> the determination of passing the point of no return by testing bprm->mm
> accurate. All failures prior to that point in flush_old_exec are
> either truly recoverable or they are fatal.
>
> Futher this consolidates all of the possible indefinite waits for ^ typo: Further

> userspace together at the top of flush_old_exec. The possible wait
> for a ptracer on PTRACE_EVENT_EXIT, the possible wait for a page fault
> to be resolved in clear_child_tid, and the possible wait for a page
> fault in exit_robust_list.
>
> This consolidation allows the creation of a mutex to replace
> cred_guard_mutex that is not held of possible indefinite userspace

can you also reword this "held of" thing here as well?

Thanks
Bernd.