From patchwork Tue Mar 2 09:01:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 392872 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 4CB8DC433DB for ; Wed, 3 Mar 2021 01:42:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0645564E62 for ; Wed, 3 Mar 2021 01:42:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236363AbhCCB2Q (ORCPT ); Tue, 2 Mar 2021 20:28:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:40154 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378876AbhCBJFT (ORCPT ); Tue, 2 Mar 2021 04:05:19 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6129864DE4; Tue, 2 Mar 2021 09:02:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1614675738; bh=/9iGZlMSTBpH3pvYK2XMp6jTFluRmMTYaBwnJWdiW6M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JvdwB42Dh4PttZChpfMeQrxV9Kh6YQrGHN1qnIGTdznaDavl+WUI1TGzTQNvOiSoK PkR8b4PKCs8Q6nXjeD2gP+FGsSdjSGWhhRMBB5XZQMRY+APDE/LMumpf7WvrXyFQI6 xRReGhHxgoify9QeDpjd4X/aKQTe3bFj14Q22Ik9Z+MUzFHTOu1BicysbTdPVVco34 5mQ5HFUhyAPNpQK+y0rXPaiYI6aq1UlQzhVLrBDurg2VecZIlHOIPrdqYaKwqI2oR8 OFfmLT9H5hc4O3arH/iRkzfjMovkVqbs7+RKQjvcAqJ7rXH8Vilc8WphlJZjRv1it7 RqDGiLBep8amg== From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Dave Martin , Mark Brown , Herbert Xu , Eric Biggers , Will Deacon , Catalin Marinas , Thomas Gleixner , Peter Zijlstra , Sebastian Andrzej Siewior , Ingo Molnar , Andy Lutomirski Subject: [PATCH v2 5/9] crypto: skcipher - disallow en/decrypt for non-task or non-softirq context Date: Tue, 2 Mar 2021 10:01:14 +0100 Message-Id: <20210302090118.30666-6-ardb@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210302090118.30666-1-ardb@kernel.org> References: <20210302090118.30666-1-ardb@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org In order to ensure that kernel mode SIMD routines will not need a scalar fallback if they run with softirqs disabled, disallow any use of the skcipher encrypt and decrypt routines from outside of task or softirq context. Signed-off-by: Ard Biesheuvel --- crypto/skcipher.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/crypto/skcipher.c b/crypto/skcipher.c index a15376245416..d1a2ba6eacbe 100644 --- a/crypto/skcipher.c +++ b/crypto/skcipher.c @@ -623,6 +623,11 @@ int crypto_skcipher_encrypt(struct skcipher_request *req) unsigned int cryptlen = req->cryptlen; int ret; + if (!(alg->cra_flags & CRYPTO_ALG_ASYNC) && + WARN_ONCE(!in_task() && !in_serving_softirq(), + "synchronous call from invalid context\n")) + return -EBUSY; + crypto_stats_get(alg); if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY; @@ -640,6 +645,11 @@ int crypto_skcipher_decrypt(struct skcipher_request *req) unsigned int cryptlen = req->cryptlen; int ret; + if (!(alg->cra_flags & CRYPTO_ALG_ASYNC) && + WARN_ONCE(!in_task() && !in_serving_softirq(), + "synchronous call from invalid context\n")) + return -EBUSY; + crypto_stats_get(alg); if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) ret = -ENOKEY;