From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from abb.hmeau.com (abb.hmeau.com [180.181.231.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79C0930C632 for ; Tue, 5 May 2026 08:51:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=180.181.231.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777971062; cv=none; b=NFKzpcS6KWqU5IJ1xkq0mHnLrUq3elfyIklMgFH5Re6JhOV4e8O4ZMTgMrEs7YjbwmxDle8bTg7OgnVrvDS5whDAHfInCuAMY4pOUbHXZY/DuikahNgGYezI4Ammm/Z+poRhgjJA2OHoM0fne/DH1cIFeTC9gDMecF+g6BvBZgA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777971062; c=relaxed/simple; bh=Oo0NjITjhNPiOzo4ibZQVD5LZPnyHviUBe6pR2/Vfec=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pAD5vMARQ5YCS1969dkOgj72aF9ESV09ClTniDVNT5zFlNP+TnppTEcg0oGtBmciL+ofv8/2rFBvm/IJd7Ngi6LyDjeI9J26q8cF7ycQfmAkWguPNwCF3Y9/bgwHFA88XhLI2c39WMZLRyBCHQS+Pa33t0gClBhBNYHYmi+Or3g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=gondor.apana.org.au; spf=pass smtp.mailfrom=gondor.apana.org.au; dkim=pass (2048-bit key) header.d=gondor.apana.org.au header.i=@gondor.apana.org.au header.b=jqlivJif; arc=none smtp.client-ip=180.181.231.80 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=gondor.apana.org.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gondor.apana.org.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gondor.apana.org.au header.i=@gondor.apana.org.au header.b="jqlivJif" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gondor.apana.org.au; s=h01; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:cc:to:subject:message-id:date: from:content-type:reply-to; bh=G7AlGtQ6kalc9B+qkfaX0+2gnGZmq/bYpL4SsN8H2S8=; b=jqlivJifwXsSpYRWvfzPZFM2EkAVIYdF41tthY4aXnMulYKeUlrl46c6E8ajLqnOAnkPGhHBGxo HR484gUzSbLFHsP/6ipYIGjPhneRCckRasRG1QPOhBpq87RWJH21qu4KFihbs3BUtMnDV3yn1Z8oi 1ICoZv7k0J1b72eBYV3v3T5FlMNe6GRHC/lWygj6vvw4LPViGZLUIa8+vAkqWj3BNYtz8PK8lahP4 Mb5TzSRXmCyzA/2vCNuZugoIhBkiIiRqjGxkHrsLP6uLIPx4oEYAVIxGZp4RVphxutmRrD0CkXvKn IfaUwsqyfvKj6iimu5UfqBaSIdRgnb2ruubw==; Received: from loth.rohan.me.apana.org.au ([192.168.167.2]) by formenos.hmeau.com with smtp (Exim 4.96 #2 (Debian)) id 1wKBUY-00BN9S-06; Tue, 05 May 2026 16:50:59 +0800 Received: by loth.rohan.me.apana.org.au (sSMTP sendmail emulation); Tue, 05 May 2026 16:50:58 +0800 Date: Tue, 5 May 2026 16:50:58 +0800 From: Herbert Xu To: Ard Biesheuvel Cc: linux-crypto@vger.kernel.org, ebiggers@kernel.org Subject: Re: [PATCH] crypto: Drop unused cipher_null crypto_alg Message-ID: References: <20260420094120.5167-1-ardb@kernel.org> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260420094120.5167-1-ardb@kernel.org> On Mon, Apr 20, 2026 at 11:41:20AM +0200, Ard Biesheuvel wrote: > The cipher_null crypto_alg cipher is never used in a meaningful way, > given that it is always wrapped in ecb(), which has its own dedicated > implementation. IOW, the cipher_null crypto_alg should never be used to > implement the ecb(cipher_null) skcipher, and using it for other things > is bogus. > > However, it is accessible from user space, and due to the nature of the > AF_ALG interface, it may be wrapped in arbitrary ways, exposing issues > in template code that wasn't written with block ciphers with a block > size of '1' in mind. > > So drop this code. > > Signed-off-by: Ard Biesheuvel > --- > crypto/crypto_null.c | 35 ++------------------ > 1 file changed, 2 insertions(+), 33 deletions(-) Patch applied. Thanks. -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt