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From: Pratyush Yadav <pratyush@kernel.org>
To: Yifei Chu <yifeichu24@gmail.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>,  Mike Rapoport
 <rppt@kernel.org>,  linux-kernel@vger.kernel.org,  Pratyush Yadav
 <pratyush@kernel.org>,  Andrew Morton <akpm@linux-foundation.org>,
  Alexander Graf <graf@amazon.com>,  linux-mm@kvack.org,
  kexec@lists.infradead.org
Subject: Re: [BUG] liveupdate: incoming/outgoing session ioctls accepted in
 wrong phase can panic
In-Reply-To: <CAPJnbgLtEUQ4Kv1ENM4ku0S0JFS8T49MEHFa4MpoT3WRuuVfFA@mail.gmail.com>
	(Yifei Chu's message of "Sun, 24 May 2026 10:44:31 -0400")
References: <CAPJnbgLtEUQ4Kv1ENM4ku0S0JFS8T49MEHFa4MpoT3WRuuVfFA@mail.gmail.com>
Date: Mon, 25 May 2026 17:26:51 +0200
Message-ID: <2vxzjysr7bno.fsf@kernel.org>
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On Sun, May 24 2026, Yifei Chu wrote:

> Hello,
>
> Short version: I found that liveupdate session ioctls can be accepted on the wrong kind of session. In my tests, that
> lets userspace drive memfd LUO into KHO restore paths for current-kernel preserved memory, which hits kho_restore_page()
> warnings and panics with panic_on_warn=1.

I already sent a fix for this:
https://lore.kernel.org/kexec/20260519122428.2378446-1-pratyush@kernel.org/

I need to do a refresh of this patch with some tests.

-- 
Regards,
Pratyush Yadav