Re: [PATCH][RFC] don't bother with path_get()/path_put() in unix_open_file()

[Al Viro <viro@zeniv.linux.org.uk>]

On Mon, Jul 14, 2025 at 10:24:11AM +0200, Christian Brauner wrote:
> On Sat, Jul 12, 2025 at 06:38:33AM +0000, Kuniyuki Iwashima wrote:
> > From: Al Viro <viro@zeniv.linux.org.uk>
> > Date: Sat, 12 Jul 2025 06:41:57 +0100
> > > Once unix_sock ->path is set, we are guaranteed that its ->path will remain
> > > unchanged (and pinned) until the socket is closed.  OTOH, dentry_open()
> > > does not modify the path passed to it.
> > > 
> > > IOW, there's no need to copy unix_sk(sk)->path in unix_open_file() - we
> > > can just pass it to dentry_open() and be done with that.
> > > 
> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> > 
> > Sounds good.  I confirmed vfs_open() copies the passed const path ptr.
> > 
> > Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
> 
> I can just throw that into the SCM_PIDFD branch?

Fine by me; the thing is, I don't have anything else in the area at the moment
(and won't until -rc1 - CLASS(get_unused_fd) series will stray there, but
it's not settled enough yet, so it's definitely the next cycle fodder).

So if you (or netdev folks) already have anything going on in the af_unix.c,
I've no problem with that thing going there.