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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 11 Jan 2024 09:37:41 -0800
Message-ID: <CAHk-=wg15ph=mEo2SqcN+6V1GYPq9U+_nCaNaDPbiPisKOj=ug@mail.gmail.com>
Subject: Re: [GIT PULL] execve updates for v6.8-rc1
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Josh Triplett <josh@joshtriplett.org>, Kees Cook <kees@kernel.org>, 
	Kees Cook <keescook@chromium.org>, linux-kernel@vger.kernel.org, 
	Alexey Dobriyan <adobriyan@gmail.com>
Content-Type: text/plain; charset="UTF-8"

On Thu, 11 Jan 2024 at 01:47, Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Two things, both related to ->atomic_open():

Yeah, I was staring at the atomic_open() cases, and just thought that
we could allocate the filp early for that.

It wouldn't matter for normal filesystems, so from a performance
standpoint it would be ok.

My handwavy thinking was that we'd remove 'filp' from the arguments we
pass around, and instead make it be a member of 'struct nameidata',
and then the different codepaths could decide that "now I need the
filp, so I'll instantiate it".

But then I looked more at the code, and it seemed to get quite messy,
quite fast.

               Linus