linux-kernel - Re: [PATCH 1/3] x86: fix access_ok() and valid_user_address() using wrong USER_PTR

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Message-ID: <CAGudoHEmtT4qXGB_t4UwVrb51+47odgU3r2Rm10_j7quMT84+Q@mail.gmail.com>
Date: Fri, 31 Oct 2025 23:01:12 +0100
From: Mateusz Guzik <mjguzik@...il.com>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: brauner@...nel.org, viro@...iv.linux.org.uk, jack@...e.cz, 
	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org, 
	tglx@...utronix.de, pfalcato@...e.de
Subject: Re: [PATCH 1/3] x86: fix access_ok() and valid_user_address() using
 wrong USER_PTR_MAX in modules

On Fri, Oct 31, 2025 at 10:46 PM Linus Torvalds
<torvalds@...ux-foundation.org> wrote:
>
> On Fri, 31 Oct 2025 at 10:42, Mateusz Guzik <mjguzik@...il.com> wrote:
> >
> > -extern unsigned long USER_PTR_MAX;
> > +extern unsigned long user_ptr_max;
>
> Yeah, this doesn't work at all.
>
> We still use USER_PTR_MAX in other places, including the linker script
> and arch/x86/lib/getuser.S
>
> So you changed about half the places to the new name, breaking the others.
>

True, but note there is no sign-off on the patch as this is not a real
submission yet.

Changing this to lower case was a last minute adjustment and it really
does not matter in this context, interestingly enough the kernel still
built just fine, just threw the following:
ld: warning: orphan section `runtime_ptr_user_ptr_max' from
`vmlinux.o' being placed in section `runtime_ptr_user_ptr_max'

Anyway, the thing which does matter in this patchset is that a riscv
kernel now builds with fs.h including runtime-const-accessors.h and
this is the bit I'm fishing for comments on.