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Date: Mon, 8 Jun 2015 08:50:03 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <bp@alien8.de>,
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        Kees Cook <keescook@chromium.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/asm/entry/32: Reinstate clearing of pt_regs->r8..r11
 on EFAULT path
Message-ID: <20150608065003.GA28899@gmail.com>
References: <1433701470-28800-1-git-send-email-dvlasenk@redhat.com>
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* Denys Vlasenko <dvlasenk@redhat.com> wrote:

> I broke this recently when I changed pt_regs->r8..r11 clearing logic
> in INT 80 code path.
> 
> There is a branch from SYSENTER/SYSCALL code to INT 80 code:
> if we fail to retrieve arg6, we return EFAULT. Before this patch,
> in this case we don't clear pt_regs->r8..r11.
> 
> This patch fixes this. The resulting code is smaller and simpler.

So how did you notice this bug - through actual info leak testing, or review?

Thanks,

	Ingo