Re: [syzbot] [hardening?] [mm?] BUG: bad usercopy in fpa_set

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Kees Cook <keescook@chromium.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	syzbot <syzbot+cb76c2983557a07cdb14@syzkaller.appspotmail.com>,
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [hardening?] [mm?] BUG: bad usercopy in fpa_set
Date: Mon, 15 Apr 2024 10:44:48 +0100	[thread overview]
Message-ID: <Zhz3EEsnGSOgnYWA@shell.armlinux.org.uk> (raw)
In-Reply-To: <c5a3598d-16dd-4aeb-904e-2084fafef9fe@I-love.SAKURA.ne.jp>

On Mon, Apr 15, 2024 at 06:38:33PM +0900, Tetsuo Handa wrote:
> On 2024/04/15 18:02, Mark Rutland wrote:
> >   08626a6056aad824 ("arm: Implement thread_struct whitelist for hardened usercopy")
> > 
> > That commit says that all accesses are bounce-buffered and bypass the check,
> > but AFAICT the fpa_set() code hasn't changed since then, so either that was
> > wrong or the user_regset_copyin() code has changed.
> 
> Then, can we go with https://lkml.kernel.org/r/0b49d91b-511f-449e-b7c3-93b2ccce6c49@I-love.SAKURA.ne.jp ?

Have you visited that URL? It doesn't point to an email containing a
patch, so sorry, I don't know what patch you're referring to.

-- 
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