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From:   Martijn Coenen <maco@android.com>
Date:   Fri, 22 Jun 2018 10:48:56 +0200
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Subject: Re: [PATCH 2/2 v2] staging: android: ashmem: Fix mmap size validation
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Daniel Colascione <dancol@google.com>,
        Alistair Strachan <astrachan@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        Todd Kjos <tkjos@android.com>,
        "open list:ANDROID DRIVERS" <devel@driverdev.osuosl.org>,
        kernel-team@android.com
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On Thu, Jun 21, 2018 at 1:29 AM, Joel Fernandes <joel@joelfernandes.org> wrote:
> Also if you look at the kernel sources, there are dozens of drivers that
> check for correct VMA size in mmap handler and fail if it isn't sized
> correctly.

If that's the case, we should definitely do it this way for ashmem as
well. Since its size is fixed after creation, preventing anyone from
mapping a larger size seems reasonable to me.

Reviewed-by: Martijn Coenen <maco@android.com>

>
> thanks!
>
>  - Joel
>