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Date: Fri, 12 May 2017 20:08:35 +0100
From: Russell King - ARM Linux <linux@armlinux.org.uk>
Message-ID: <20170512190835.GN22219@n2100.armlinux.org.uk>
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Sender: Russell King - ARM Linux <linux@armlinux.org.uk>
Subject: Re: [kernel-hardening] Re: [PATCH v9 1/4] syscalls: Verify address
 limit before returning to user-mode
List-Archive: <https://lore.kernel.org/kernel-hardening/>
List-Post: <mailto:kernel-hardening@lists.openwall.com>
To: Kees Cook <keescook@chromium.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>, Linus Torvalds <torvalds@linux-foundation.org>, Thomas Garnier <thgarnie@google.com>, Greg KH <greg@kroah.com>, Ingo Molnar <mingo@kernel.org>, Daniel Micay <danielmicay@gmail.com>, Heiko Carstens <heiko.carstens@de.ibm.com>, Dave Hansen <dave.hansen@intel.com>, Arnd Bergmann <arnd@arndb.de>, Thomas Gleixner <tglx@linutronix.de>, David Howells <dhowells@redhat.com>, =?iso-8859-1?Q?Ren=E9?= Nyffenegger <mail@renenyffenegger.ch>, Andrew Morton <akpm@linux-foundation.org>, "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>, "Eric W . Biederman" <ebiederm@xmission.com>, Oleg Nesterov <oleg@redhat.com>, Pavel Tikhomirov <ptikhomirov@virtuozzo.com>, Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>, Paolo Bonzini <pbonzini@redhat.com>, Rik van Riel <riel@redhat.com>, Josh Poimboeuf <jpoimboe@redhat.com>, Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Christian Borntraeger <borntraeger@de.ibm.com>, Will Deacon <will.deacon@arm.com>, Catalin Marinas <catalin.marinas@arm.com>, Mark Rutland <mark.rutland@arm.com>, James Morse <james.morse@arm.com>, linux-s390 <linux-s390@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>, Linux API <linux-api@vger.kernel.org>, the arch/x86 maintainers <x86@kernel.org>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, Kernel Hardening <kernel-hardening@lists.openwall.com>, Peter Zijlstra <a.p.zijlstra@chello.nl>, Al Viro <viro@zeniv.linux.org.uk>
List-ID: <linux-s390.vger.kernel.org>

On Fri, May 12, 2017 at 12:01:59PM -0700, Kees Cook wrote:
> Yeah, the risk for "corrupted addr_limit" is mainly a concern for
> archs with addr_limit on the kernel stack. If I'm reading things
> correctly, that means, from the archs I've been paying closer
> attention to, it's an issue for arm, mips, and powerpc:

I'd first want to uninline everything in uaccess.h first that makes
use of access_ok() - which I think is something that needs to happen
anyway.

-- 
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