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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 9D3A4C43610 for ; Thu, 22 Nov 2018 10:01:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 617C420831 for ; Thu, 22 Nov 2018 10:01:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="pPsv0b2k" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 617C420831 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=163.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393651AbeKVUjx (ORCPT ); Thu, 22 Nov 2018 15:39:53 -0500 Received: from m12-14.163.com ([220.181.12.14]:49933 "EHLO m12-14.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390330AbeKVUjx (ORCPT ); Thu, 22 Nov 2018 15:39:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=AvYeQh1yeGK7rPhdeT ptzjlRCeoXDMojg/A8aa/hvys=; b=pPsv0b2k7CX8TIhSbUSi9pjsq5gl0Ypw1e rHbVEel5zzEgxeYI+Ueo29c/jDnNIeRoB3IMRIFY0u9p1/VCUcNp9wN7GAiOPnDE WlMbpoWzYXtNrDcX2lwrK3+qVElgaC/AAzIoliZBT2xth0FORrwmvSjRamiSDUII F9++VVZIM= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp10 (Coremail) with SMTP id DsCowAAnpdFWfvZbdqJJBQ--.64751S3; Thu, 22 Nov 2018 18:00:57 +0800 (CST) From: Pan Bian To: Herbert Xu , "David S. Miller" Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH] crypto: do not free algorithm before using Date: Thu, 22 Nov 2018 18:00:16 +0800 Message-Id: <1542880816-63838-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: DsCowAAnpdFWfvZbdqJJBQ--.64751S3 X-Coremail-Antispam: 1Uf129KBjvJXoWxAFyrCF4fXFW3Zw1kCrWUtwb_yoW5Zr1Dpr Z5KrWktFn5Jrs8urZ7GFs5XrykWrW09a43WrW8Kw4ayrs2qw18JrWIyry5AF4j9FWkJa43 GFWvkr1F9a1UJaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jDa9-UUUUU= X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBZxoHcletsFUyfQAAsY Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In multiple functions, the algorithm fields are read after its reference is dropped through crypto_mod_put. In this case, the algorithm memory may be freed, resulting in use-after-free bugs. This patch delays the put operation until the algorithm is never used. Signed-off-by: Pan Bian --- crypto/cbc.c | 6 ++++-- crypto/cfb.c | 6 ++++-- crypto/pcbc.c | 6 ++++-- 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/crypto/cbc.c b/crypto/cbc.c index b761b1f..dd5f332 100644 --- a/crypto/cbc.c +++ b/crypto/cbc.c @@ -140,9 +140,8 @@ static int crypto_cbc_create(struct crypto_template *tmpl, struct rtattr **tb) spawn = skcipher_instance_ctx(inst); err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst), CRYPTO_ALG_TYPE_MASK); - crypto_mod_put(alg); if (err) - goto err_free_inst; + goto err_put_alg; err = crypto_inst_setname(skcipher_crypto_instance(inst), "cbc", alg); if (err) @@ -174,12 +173,15 @@ static int crypto_cbc_create(struct crypto_template *tmpl, struct rtattr **tb) err = skcipher_register_instance(tmpl, inst); if (err) goto err_drop_spawn; + crypto_mod_put(alg); out: return err; err_drop_spawn: crypto_drop_spawn(spawn); +err_put_alg: + crypto_mod_put(alg); err_free_inst: kfree(inst); goto out; diff --git a/crypto/cfb.c b/crypto/cfb.c index a0d68c0..20987d0 100644 --- a/crypto/cfb.c +++ b/crypto/cfb.c @@ -286,9 +286,8 @@ static int crypto_cfb_create(struct crypto_template *tmpl, struct rtattr **tb) spawn = skcipher_instance_ctx(inst); err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst), CRYPTO_ALG_TYPE_MASK); - crypto_mod_put(alg); if (err) - goto err_free_inst; + goto err_put_alg; err = crypto_inst_setname(skcipher_crypto_instance(inst), "cfb", alg); if (err) @@ -317,12 +316,15 @@ static int crypto_cfb_create(struct crypto_template *tmpl, struct rtattr **tb) err = skcipher_register_instance(tmpl, inst); if (err) goto err_drop_spawn; + crypto_mod_put(alg); out: return err; err_drop_spawn: crypto_drop_spawn(spawn); +err_put_alg: + crypto_mod_put(alg); err_free_inst: kfree(inst); goto out; diff --git a/crypto/pcbc.c b/crypto/pcbc.c index ef802f6..8aa1014 100644 --- a/crypto/pcbc.c +++ b/crypto/pcbc.c @@ -244,9 +244,8 @@ static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb) spawn = skcipher_instance_ctx(inst); err = crypto_init_spawn(spawn, alg, skcipher_crypto_instance(inst), CRYPTO_ALG_TYPE_MASK); - crypto_mod_put(alg); if (err) - goto err_free_inst; + goto err_put_alg; err = crypto_inst_setname(skcipher_crypto_instance(inst), "pcbc", alg); if (err) @@ -275,12 +274,15 @@ static int crypto_pcbc_create(struct crypto_template *tmpl, struct rtattr **tb) err = skcipher_register_instance(tmpl, inst); if (err) goto err_drop_spawn; + crypto_mod_put(alg); out: return err; err_drop_spawn: crypto_drop_spawn(spawn); +err_put_alg: + crypto_mod_put(alg); err_free_inst: kfree(inst); goto out; -- 2.7.4