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Date: Sun, 4 May 2025 15:43:07 -0700
From: Kees Cook <kees@kernel.org>
To: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@kernel.org>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-tip-commits@vger.kernel.org,
	Andy Lutomirski <luto@kernel.org>, Brian Gerst <brgerst@gmail.com>,
	"Chang S. Bae" <chang.seok.bae@intel.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Linus Torvalds <torvalds@linux-foundation.org>, x86@kernel.org
Subject: Re: hardened_usercopy 32-bit (was: Re: [tip: x86/merge] x86/fpu:
 Make task_struct::thread constant size)
Message-ID: <202505041541.C3D97BE@keescook>
References: <20250503120712.GJaBYG8A-D77MllFZ3@fat_crate.local>
 <202505041418.F47130C4C8@keescook>
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In-Reply-To: <202505041418.F47130C4C8@keescook>

On Sun, May 04, 2025 at 03:30:38PM -0700, Kees Cook wrote:
> However, I can't test this patch -- I'm not able to reproduce the problem
> either, even with your .config. What hardware are you using?

Oh, wait, yes, I reproduced it. I just didn't actually log in or wait for
complex daemons to start. Without my patch I quickly see the crashes. With
my patch, everything is fine. So, I can confirm that fixes it.

-- 
Kees Cook