From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B4ACC433EF for ; Wed, 20 Jul 2022 09:41:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231450AbiGTJlZ (ORCPT ); Wed, 20 Jul 2022 05:41:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236348AbiGTJlY (ORCPT ); Wed, 20 Jul 2022 05:41:24 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 519DE5A2D8 for ; Wed, 20 Jul 2022 02:41:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E4B4361B56 for ; Wed, 20 Jul 2022 09:41:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C183AC3411E; Wed, 20 Jul 2022 09:41:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658310082; bh=0Uh7HU+pZdlkv+nXlUEIbOCQe7d9i8cnyad1o6EdCak=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=REyJ8w41hzygC6bjYFOTuXSBcmkl3h85awz7i5ifAyKH422K/3kkUE6nmDG7d9pxY /FITzayhhmkiQf0rGMVdT0e+OJ4BOgCIkdJhqP7yCbqbNoP3iZ7/uD/mytl0yULWBs JE2h51gok/4AbR8MKJW2msOyR+l4oNKLPvy2mpBd1I5Pgh62t3MfuxRBbGjigfz2PE dcImcQzGe6T6bxFp9boDVFxHTK4kpXKwheR5nIW0ACkZVYQNztDcDYMsGMlU+9D9Th +gaMaXSsDK4jMzORkvzHFusfBJloi9e6KesxXhRZhTChjgHNd58s9gj+dBah8rnh1f AiJxM7wu4LfdQ== Date: Wed, 20 Jul 2022 10:41:16 +0100 From: Will Deacon To: GUO Zihua Cc: linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, herbert@gondor.apana.org.au, davem@davemloft.net, catalin.marinas@arm.com, ebiggers@kernel.org Subject: Re: [PATCH v2] arm64/crypto: poly1305 fix a read out-of-bound Message-ID: <20220720094116.GC15752@willie-the-truck> References: <20220712075031.29061-1-guozihua@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220712075031.29061-1-guozihua@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Tue, Jul 12, 2022 at 03:50:31PM +0800, GUO Zihua wrote: > A kasan error was reported during fuzzing: [...] > This patch fixes the issue by calling poly1305_init_arm64() instead of > poly1305_init_arch(). This is also the implementation for the same > algorithm on arm platform. > > Fixes: f569ca164751 ("crypto: arm64/poly1305 - incorporate OpenSSL/CRYPTOGAMS NEON implementation") > Cc: stable@vger.kernel.org > Signed-off-by: GUO Zihua > --- > arch/arm64/crypto/poly1305-glue.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) I'm not a crypto guy by any stretch of the imagination, but Ard is out at the moment and this looks like an important fix so I had a crack at reviewing it. > diff --git a/arch/arm64/crypto/poly1305-glue.c b/arch/arm64/crypto/poly1305-glue.c > index 9c3d86e397bf..1fae18ba11ed 100644 > --- a/arch/arm64/crypto/poly1305-glue.c > +++ b/arch/arm64/crypto/poly1305-glue.c > @@ -52,7 +52,7 @@ static void neon_poly1305_blocks(struct poly1305_desc_ctx *dctx, const u8 *src, > { > if (unlikely(!dctx->sset)) { > if (!dctx->rset) { > - poly1305_init_arch(dctx, src); > + poly1305_init_arm64(&dctx->h, src); > src += POLY1305_BLOCK_SIZE; > len -= POLY1305_BLOCK_SIZE; > dctx->rset = 1; With this change, we no longer initialise dctx->buflen to 0 as part of the initialisation. Looking at neon_poly1305_do_update(), I'm a bit worried that we could land in the 'if (likely(len >= POLY1305_BLOCK_SIZE))' block, end up with len == 0 and fail to set dctx->buflen. Is this a problem, or is my ignorance showing? Will