From mboxrd@z Thu Jan  1 00:00:00 1970
From: laura@labbott.name (Laura Abbott)
Date: Tue, 16 Feb 2016 10:48:31 -0800
Subject: [PATCH] arm64: mm: Mark .rodata as RO
In-Reply-To: <CAGXu5jLpj=ue49_N+LOYvtZcU3rpFR5=WTG15ySDOWprvRzFUA@mail.gmail.com>
References: <1455293599-6974-1-git-send-email-jeremy.linton@arm.com>
 <20160212182527.GG20262@leverpostej>
 <CAGXu5jLpj=ue49_N+LOYvtZcU3rpFR5=WTG15ySDOWprvRzFUA@mail.gmail.com>
Message-ID: <56C36EFF.9060900@labbott.name>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 2/16/16 10:10 AM, Kees Cook wrote:
> On Fri, Feb 12, 2016 at 10:25 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> On Fri, Feb 12, 2016 at 10:13:19AM -0600, Jeremy Linton wrote:
>>> Currently the .rodata section is actually still executable when DEBUG_RODATA
>>> is enabled. This changes that so the .rodata is actually read only, no execute.
>>>
>>> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
>
> Yikes, good catch. Is anyone running the lkdtm tests that check these things?
>

I don't think the current lkdtm test would have caught this since the exec
test is using rw data and not ro data. That test could be expanded though
to include a rodata buffer as well.
  
Thanks,
Laura

From mboxrd@z Thu Jan  1 00:00:00 1970
Reply-To: kernel-hardening@lists.openwall.com
References: <1455293599-6974-1-git-send-email-jeremy.linton@arm.com>
 <20160212182527.GG20262@leverpostej>
 <CAGXu5jLpj=ue49_N+LOYvtZcU3rpFR5=WTG15ySDOWprvRzFUA@mail.gmail.com>
From: Laura Abbott <laura@labbott.name>
Message-ID: <56C36EFF.9060900@labbott.name>
Date: Tue, 16 Feb 2016 10:48:31 -0800
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Subject: [kernel-hardening] Re: [PATCH] arm64: mm: Mark .rodata as RO
To: Kees Cook <keescook@chromium.org>, Mark Rutland <mark.rutland@arm.com>
Cc: Jeremy Linton <jeremy.linton@arm.com>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, "Suzuki K. Poulose" <suzuki.poulose@arm.com>, Will Deacon <will.deacon@arm.com>, Catalin Marinas <catalin.marinas@arm.com>, "kernel-hardening@lists.openwall.com" <kernel-hardening@lists.openwall.com>
List-ID: <kernel-hardening.lists.openwall.com>

On 2/16/16 10:10 AM, Kees Cook wrote:
> On Fri, Feb 12, 2016 at 10:25 AM, Mark Rutland <mark.rutland@arm.com> wrote:
>> On Fri, Feb 12, 2016 at 10:13:19AM -0600, Jeremy Linton wrote:
>>> Currently the .rodata section is actually still executable when DEBUG_RODATA
>>> is enabled. This changes that so the .rodata is actually read only, no execute.
>>>
>>> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
>
> Yikes, good catch. Is anyone running the lkdtm tests that check these things?
>

I don't think the current lkdtm test would have caught this since the exec
test is using rw data and not ro data. That test could be expanded though
to include a rodata buffer as well.
  
Thanks,
Laura