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Date:   Wed, 9 Nov 2022 17:44:56 +0000
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     linux-kernel@vger.kernel.org, Albert Ou <aou@eecs.berkeley.edu>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
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Subject: Re: [PATCH v1 2/2] stackprotector: actually use get_random_canary()
Message-ID: <Y2vnGFuj5N9/o/Ia@arm.com>
References: <20221023203208.118919-1-Jason@zx2c4.com>
 <20221023203208.118919-3-Jason@zx2c4.com>
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On Sun, Oct 23, 2022 at 10:32:08PM +0200, Jason A. Donenfeld wrote:
> The RNG always mixes in the Linux version extremely early in boot. It
> also always includes a cycle counter, not only during early boot, but
> each and every time it is invoked prior to being fully initialized.
> Together, this means that the use of additional xors inside of the
> various stackprotector.h files is superfluous and over-complicated.
> Instead, we can get exactly the same thing, but better, by just calling
> `get_random_canary()`.
> 
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> ---
>  arch/arm/include/asm/stackprotector.h     |  9 +--------
>  arch/arm64/include/asm/stackprotector.h   |  9 +--------

For arm64:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>