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Date: Mon, 15 Apr 2024 18:38:33 +0900
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Subject: Re: [syzbot] [hardening?] [mm?] BUG: bad usercopy in fpa_set
To: Mark Rutland <mark.rutland@arm.com>,
        "Russell King (Oracle)" <linux@armlinux.org.uk>,
        Kees Cook <keescook@chromium.org>
Cc: Linux ARM <linux-arm-kernel@lists.infradead.org>,
        syzbot <syzbot+cb76c2983557a07cdb14@syzkaller.appspotmail.com>,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
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From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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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 ?