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Date: Mon, 4 May 2026 02:24:42 -0700
From: Eric Biggers <ebiggers@kernel.org>
To: linux-crypto@vger.kernel.org, Herbert Xu <herbert@gondor.apana.org.au>
Cc: linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org,
	Taeyang Lee <0wn@theori.io>, Brian Pak <bpak@theori.io>,
	Juno Im <juno@theori.io>, Jungwon Lim <setuid0@theori.io>,
	Tim Becker <tjbecker@theori.io>,
	Demi Marie Obenour <demiobenour@gmail.com>,
	Feng Ning <feng@innora.ai>, stable@vger.kernel.org
Subject: Re: [PATCH v2] crypto: af_alg - Remove zero-copy support from AF_ALG
Message-ID: <20260504092442.GA2486@quark>
References: <20260504070724.GC112568@sol>
 <20260504071025.180058-1-ebiggers@kernel.org>
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In-Reply-To: <20260504071025.180058-1-ebiggers@kernel.org>

On Mon, May 04, 2026 at 12:10:25AM -0700, Eric Biggers wrote:
> Thus, the risks of the zero-copy support in AF_ALG vastly outweigh its
> benefits.  Just remove it.

I realized that the "hash" algorithm type still does zero-copy even
after this patch.  I.e. this patch affects only "skcipher" and "aead".
Those are the more important ones, but we should do "hash" too.

The diff is still fine, but I'll adjust the patch description to clarify
the scope, and send a separate patch to handle "hash".

- Eric