Re: [PATCH v2 00/24] exec: Move unshare_files and guarantee files_struct.count is correct

[Al Viro]

On Fri, Nov 20, 2020 at 04:05:47PM -0800, Linus Torvalds wrote:
> On Fri, Nov 20, 2020 at 3:11 PM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote:
> >
> > This set of changes cleanups of the code in exec so hopefully this code
> > will not regress again.  Then it adds helpers and fixes the users of
> > files_struct so the reference count is only incremented if COPY_FILES is
> > passed to clone (or if io_uring takes a reference).  Then it removes
> > helpers (get_files_struct, __install_fd, __alloc_fd, __close_fd) that
> > are no longer needed and if used would encourage code that increments
> > the count of files_struct somewhere besides in clone when COPY_FILES is
> > passed.
> 
> I'm not seeing anything that triggered me going "that looks dodgy". It
> all looks like nice cleanups.
> 
> But that's just from reading the patches (and in some cases going and
> looking at the context), so I didn't actually _test_ any of it. It all
> looks sane to me, though, and the fact that it removes a fair number
> of lines of code is always a good sign.
> 
> It would be good for people to review and test (Al? Oleg? others?),
> but my gut feel is "this is good".

Will check (sorry, the last couple of weeks had been bloody awful -
off-net and very short on sleep); I'm digging through the piles of
email right now.