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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 286A5C433FF for ; Mon, 29 Jul 2019 19:32:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E90372070B for ; Mon, 29 Jul 2019 19:32:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564428729; bh=/mMcL1qO+DoVheTOpWO+mEUa2orPdN6aPdPc7je13yA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OxUUk665DrzwpO988vRbv7kVdjLn55jqKE7bJPWlkvXJq/CWszmThSCPJ7FI5M5qJ DgR2JW8MeopA/Lhb+4Da1tzZ9V5WNorsq/S8p5BvZHH4ZzS3V0+52mtf5ioixpstuy ucVMJLTEOsKlrtTeo+hIritBAHYcAqKExYOtbZAw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730215AbfG2TcI (ORCPT ); Mon, 29 Jul 2019 15:32:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:45232 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729389AbfG2TcE (ORCPT ); Mon, 29 Jul 2019 15:32:04 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1AE022070B; Mon, 29 Jul 2019 19:32:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564428723; bh=/mMcL1qO+DoVheTOpWO+mEUa2orPdN6aPdPc7je13yA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qaHypbMm6/DkMSXM6PA+h/fv59H8bmXbVoq0B96N8+N69FMoN3Q6jsscaKB2oL9R3 +IyxmeT+dgkrnj2S4eD2Hd9MuhchQ5vjztutLvKfaw+cQcQZoY2lXGJ8zSRoZDuNfw QXZ293WAg8qb0m3Gdrf/3KKrNUOJZP+qihJEZ8LM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Horia Geanta , Iuliana Prodan , Sascha Hauer , Ard Biesheuvel , Herbert Xu Subject: [PATCH 4.14 166/293] crypto: caam - limit output IV to CBC to work around CTR mode DMA issue Date: Mon, 29 Jul 2019 21:20:57 +0200 Message-Id: <20190729190837.249555862@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190729190820.321094988@linuxfoundation.org> References: <20190729190820.321094988@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel commit ed527b13d800dd515a9e6c582f0a73eca65b2e1b upstream. The CAAM driver currently violates an undocumented and slightly controversial requirement imposed by the crypto stack that a buffer referred to by the request structure via its virtual address may not be modified while any scatterlists passed via the same request structure are mapped for inbound DMA. This may result in errors like alg: aead: decryption failed on test 1 for gcm_base(ctr-aes-caam,ghash-generic): ret=74 alg: aead: Failed to load transform for gcm(aes): -2 on non-cache coherent systems, due to the fact that the GCM driver passes an IV buffer by virtual address which shares a cacheline with the auth_tag buffer passed via a scatterlist, resulting in corruption of the auth_tag when the IV is updated while the DMA mapping is live. Since the IV that is returned to the caller is only valid for CBC mode, and given that the in-kernel users of CBC (such as CTS) don't trigger the same issue as the GCM driver, let's just disable the output IV generation for all modes except CBC for the time being. Fixes: 854b06f76879 ("crypto: caam - properly set IV after {en,de}crypt") Cc: Horia Geanta Cc: Iuliana Prodan Reported-by: Sascha Hauer Cc: Signed-off-by: Ard Biesheuvel Reviewed-by: Horia Geanta Signed-off-by: Herbert Xu [ Horia: backported to 4.14, 4.19 ] Signed-off-by: Horia Geantă Signed-off-by: Greg Kroah-Hartman --- drivers/crypto/caam/caamalg.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/crypto/caam/caamalg.c +++ b/drivers/crypto/caam/caamalg.c @@ -853,6 +853,7 @@ static void ablkcipher_encrypt_done(stru struct ablkcipher_request *req = context; struct ablkcipher_edesc *edesc; struct crypto_ablkcipher *ablkcipher = crypto_ablkcipher_reqtfm(req); + struct caam_ctx *ctx = crypto_ablkcipher_ctx(ablkcipher); int ivsize = crypto_ablkcipher_ivsize(ablkcipher); #ifdef DEBUG @@ -877,10 +878,11 @@ static void ablkcipher_encrypt_done(stru /* * The crypto API expects us to set the IV (req->info) to the last - * ciphertext block. This is used e.g. by the CTS mode. + * ciphertext block when running in CBC mode. */ - scatterwalk_map_and_copy(req->info, req->dst, req->nbytes - ivsize, - ivsize, 0); + if ((ctx->cdata.algtype & OP_ALG_AAI_MASK) == OP_ALG_AAI_CBC) + scatterwalk_map_and_copy(req->info, req->dst, req->nbytes - + ivsize, ivsize, 0); /* In case initial IV was generated, copy it in GIVCIPHER request */ if (edesc->iv_dir == DMA_FROM_DEVICE) { @@ -1609,10 +1611,11 @@ static int ablkcipher_decrypt(struct abl /* * The crypto API expects us to set the IV (req->info) to the last - * ciphertext block. + * ciphertext block when running in CBC mode. */ - scatterwalk_map_and_copy(req->info, req->src, req->nbytes - ivsize, - ivsize, 0); + if ((ctx->cdata.algtype & OP_ALG_AAI_MASK) == OP_ALG_AAI_CBC) + scatterwalk_map_and_copy(req->info, req->src, req->nbytes - + ivsize, ivsize, 0); /* Create and submit job descriptor*/ init_ablkcipher_job(ctx->sh_desc_dec, ctx->sh_desc_dec_dma, edesc, req);