Re: [PATCH] exec: do_close_on_exec() before taking exec_update_lock

[Jann Horn]

On Fri, Sep 11, 2026 at 1:30 PM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote:
> It has always been a requirement that in exec_update_lock not be held
> for writing over any userspace accesses.  Which is why it is taken in
> right after exec_mmap is done updating userspace.
>
> In the original version I missed that do_close_on_exec calls flush
> which can block waiting on userspace (Is that just a fuse thing?).

It's particularly egregious in FUSE, but I think network filesystems
can also block on network I/O in there.

> Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>

Thanks for the review!