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From: Arnd Bergmann <arnd@arndb.de>
To: Kees Cook <keescook@chromium.org>
Cc: Paul Mackerras <paulus@samba.org>,
	"David S. Miller" <davem@davemloft.net>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Eric Biggers <ebiggers@google.com>,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>,
	linux-ppp@vger.kernel.org, Networking <netdev@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] ppp: mppe: Remove VLA usage
Date: Mon, 16 Jul 2018 13:01:34 +0200	[thread overview]
Message-ID: <CAK8P3a1tph9VPJnYYhBvH_1wZ79wXDvfnJt_CEruj3T-TBG1jg@mail.gmail.com> (raw)
In-Reply-To: <20180716040516.GA32783@beast>

On Mon, Jul 16, 2018 at 6:05 AM, Kees Cook <keescook@chromium.org> wrote:
> In the quest to remove all stack VLA usage from the kernel[1], this
> removes the discouraged use of AHASH_REQUEST_ON_STACK (and associated
> VLA) by switching to shash directly and keeping the associated descriptor
> allocated with the regular state on the heap.
>
> [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
>
> Signed-off-by: Kees Cook <keescook@chromium.org>

I had concerns at first that this approach might make it slower, but
upon reading through implementation of the shash_ahash_ implementation,
I concluded that it can only be better than before, improving both
performance and stack usage.

Acked-by: Arnd Bergmann <arnd@arndb.de>

  reply	other threads:[~2018-07-16 11:01 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-16  4:05 [PATCH] ppp: mppe: Remove VLA usage Kees Cook
2018-07-16 11:01 ` Arnd Bergmann [this message]
2018-08-02 23:27   ` Kees Cook
2018-08-03  3:13     ` Paul Mackerras
2018-07-16 17:36 ` Eric Biggers

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