From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>,
Sashiko AI review <sashiko-bot@kernel.org>,
Lorenzo Stoakes <ljs@kernel.org>,
David Hildenbrand <david@kernel.org>,
Michal Hocko <mhocko@suse.com>, Mike Rapoport <rppt@kernel.org>,
Peter Xu <peterx@redhat.com>,
Suren Baghdasaryan <surenb@google.com>,
Vlastimil Babka <vbabka@kernel.org>,
Balbir Singh <balbirs@nvidia.com>,
Andrew Morton <akpm@linux-foundation.org>,
Kiryl Shutsemau <kas@kernel.org>
Subject: Re: [PATCH 5.10.y] userfaultfd: gate must_wait writability check on pte_present()
Date: Fri, 3 Jul 2026 22:05:18 -0400 [thread overview]
Message-ID: <2026070315-stable-reply-0024@kernel.org> (raw)
In-Reply-To: <20260702154859.975356-1-kas@kernel.org>
On Thu, Jul 02, 2026 at 16:48:59 +0100, Kiryl Shutsemau wrote:
> userfaultfd_must_wait() and userfaultfd_huge_must_wait() read the PTE
> without taking the page table lock and then apply pte_write() /
> huge_pte_write() to it. Those accessors decode bits from the present
> encoding only; on a swap or migration entry they read the offset bits that
> happen to share the same position and return an undefined result.
Queued for 5.10.y, thanks!
--
Thanks,
Sasha
prev parent reply other threads:[~2026-07-04 2:05 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-02 12:52 FAILED: patch "[PATCH] userfaultfd: gate must_wait writability check on" failed to apply to 5.10-stable tree gregkh
2026-07-02 15:48 ` [PATCH 5.10.y] userfaultfd: gate must_wait writability check on pte_present() Kiryl Shutsemau
2026-07-04 2:05 ` Sasha Levin [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2026070315-stable-reply-0024@kernel.org \
--to=sashal@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=balbirs@nvidia.com \
--cc=david@kernel.org \
--cc=kas@kernel.org \
--cc=ljs@kernel.org \
--cc=mhocko@suse.com \
--cc=peterx@redhat.com \
--cc=rppt@kernel.org \
--cc=sashiko-bot@kernel.org \
--cc=stable@vger.kernel.org \
--cc=surenb@google.com \
--cc=vbabka@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox