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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 DA746C43381 for ; Fri, 22 Mar 2019 11:42:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F54F204FD for ; Fri, 22 Mar 2019 11:42:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553254969; bh=MvlmVx8z8eYHtP5KcQmKIwrr7yMb1kx6YngYt8hykJA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=u09lITGYKajWJ6HxXi8ZOdsbn5vsXnVSC7h/DFUVNPSbyobDNo5we4rk3eL5V9oCL Z4wHdaOpWwHmbo8ZdiAhL3/dOzDhoMJAnQrFSojUu1KTFPxP4Wjxiqf8jV0r8yLwOR kMimSGohBhD+G9fDGoPW8aTs2jM2LkOUg3WnyIEM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730809AbfCVLms (ORCPT ); Fri, 22 Mar 2019 07:42:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:45294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731574AbfCVLmp (ORCPT ); Fri, 22 Mar 2019 07:42:45 -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 62761204FD; Fri, 22 Mar 2019 11:42:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553254963; bh=MvlmVx8z8eYHtP5KcQmKIwrr7yMb1kx6YngYt8hykJA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DI7zbC3UZjlCDjsUSWcH+GmttS+tRWi+7QyUGkF7ITT1X814eHmI9Hdq+lSWOyw69 W60Y2hAO0CCaRPJ7/JAqEOkrcD+Bd+n8dlsZ3szKHJrimeZHk9hy4QtMUP8Rgsftil jpejtUyMPNKyZ8BruxeEWTL85j0RMixFj+xkLE9M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , Herbert Xu Subject: [PATCH 4.9 046/118] crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails Date: Fri, 22 Mar 2019 12:15:18 +0100 Message-Id: <20190322111219.592345442@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111215.873964544@linuxfoundation.org> References: <20190322111215.873964544@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers commit ba7d7433a0e998c902132bd47330e355a1eaa894 upstream. Some algorithms have a ->setkey() method that is not atomic, in the sense that setting a key can fail after changes were already made to the tfm context. In this case, if a key was already set the tfm can end up in a state that corresponds to neither the old key nor the new key. It's not feasible to make all ->setkey() methods atomic, especially ones that have to key multiple sub-tfms. Therefore, make the crypto API set CRYPTO_TFM_NEED_KEY if ->setkey() fails and the algorithm requires a key, to prevent the tfm from being used until a new key is set. Note: we can't set CRYPTO_TFM_NEED_KEY for OPTIONAL_KEY algorithms, so ->setkey() for those must nevertheless be atomic. That's fine for now since only the crc32 and crc32c algorithms set OPTIONAL_KEY, and it's not intended that OPTIONAL_KEY be used much. [Cc stable mainly because when introducing the NEED_KEY flag I changed AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG previously didn't have this problem. So these "incompletely keyed" states became theoretically accessible via AF_ALG -- though, the opportunities for causing real mischief seem pretty limited.] Fixes: 9fa68f620041 ("crypto: hash - prevent using keyed hashes without setting key") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/ahash.c | 28 +++++++++++++++++++--------- crypto/shash.c | 18 +++++++++++++----- 2 files changed, 32 insertions(+), 14 deletions(-) --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -189,6 +189,21 @@ static int ahash_setkey_unaligned(struct return ret; } +static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key, + unsigned int keylen) +{ + return -ENOSYS; +} + +static void ahash_set_needkey(struct crypto_ahash *tfm) +{ + const struct hash_alg_common *alg = crypto_hash_alg_common(tfm); + + if (tfm->setkey != ahash_nosetkey && + !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY)) + crypto_ahash_set_flags(tfm, CRYPTO_TFM_NEED_KEY); +} + int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, unsigned int keylen) { @@ -200,20 +215,16 @@ int crypto_ahash_setkey(struct crypto_ah else err = tfm->setkey(tfm, key, keylen); - if (err) + if (unlikely(err)) { + ahash_set_needkey(tfm); return err; + } crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); return 0; } EXPORT_SYMBOL_GPL(crypto_ahash_setkey); -static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key, - unsigned int keylen) -{ - return -ENOSYS; -} - static inline unsigned int ahash_align_buffer_size(unsigned len, unsigned long mask) { @@ -482,8 +493,7 @@ static int crypto_ahash_init_tfm(struct if (alg->setkey) { hash->setkey = alg->setkey; - if (!(alg->halg.base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY)) - crypto_ahash_set_flags(hash, CRYPTO_TFM_NEED_KEY); + ahash_set_needkey(hash); } if (alg->export) hash->export = alg->export; --- a/crypto/shash.c +++ b/crypto/shash.c @@ -52,6 +52,13 @@ static int shash_setkey_unaligned(struct return err; } +static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg) +{ + if (crypto_shash_alg_has_setkey(alg) && + !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY)) + crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY); +} + int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, unsigned int keylen) { @@ -64,8 +71,10 @@ int crypto_shash_setkey(struct crypto_sh else err = shash->setkey(tfm, key, keylen); - if (err) + if (unlikely(err)) { + shash_set_needkey(tfm, shash); return err; + } crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); return 0; @@ -367,7 +376,8 @@ int crypto_init_shash_ops_async(struct c crt->final = shash_async_final; crt->finup = shash_async_finup; crt->digest = shash_async_digest; - crt->setkey = shash_async_setkey; + if (crypto_shash_alg_has_setkey(alg)) + crt->setkey = shash_async_setkey; crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) & CRYPTO_TFM_NEED_KEY); @@ -389,9 +399,7 @@ static int crypto_shash_init_tfm(struct hash->descsize = alg->descsize; - if (crypto_shash_alg_has_setkey(alg) && - !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY)) - crypto_shash_set_flags(hash, CRYPTO_TFM_NEED_KEY); + shash_set_needkey(hash, alg); return 0; }