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Date: Wed, 10 Jun 2026 13:33:25 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Samuel Moelius <sam.moelius@trailofbits.com>
Cc: David Hildenbrand <david@kernel.org>, Jason Gunthorpe <jgg@ziepe.ca>,
 John Hubbard <jhubbard@nvidia.com>, Peter Xu <peterx@redhat.com>,
 "open list:MEMORY MANAGEMENT - GUP (GET USER PAGES)" <linux-mm@kvack.org>,
 open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm/gup_test: reject wrapped user ranges
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References: <20260609004814.1240586.6294d614ac80.gup-test-range-end-wrap@trailofbits.com>
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On Wed, 10 Jun 2026 13:22:32 -0400 Samuel Moelius <sam.moelius@trailofbits.com> wrote:

> > >       start_time = ktime_get();
> > > -     for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) {
> > > +     for (addr = gup->addr; addr < end; addr = next) {
> > >               if (nr != gup->nr_pages_per_call)
> > >                       break;
> > >
> > >               next = addr + nr * PAGE_SIZE;
> >
> > Sashiko AI review identified a pre-existing possible overflow here on
> > 32-bit machines.
> >
> > https://sashiko.dev/#/patchset/20260609004814.1240586.6294d614ac80.gup-test-range-end-wrap@trailofbits.com
> 
> Does the __u64 or Sashiko AI point require action from me?

Not really.  The patch makes the code better, that's what counts!