From patchwork Wed Nov 11 09:22:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 11897217 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A52F915E6 for ; Wed, 11 Nov 2020 09:24:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C9EB20809 for ; Wed, 11 Nov 2020 09:24:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727082AbgKKJY2 (ORCPT ); Wed, 11 Nov 2020 04:24:28 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:2083 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726134AbgKKJYC (ORCPT ); Wed, 11 Nov 2020 04:24:02 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4CWK583sbfz67JlR; Wed, 11 Nov 2020 17:22:36 +0800 (CST) Received: from roberto-HP-EliteDesk-800-G2-DM-65W.huawei.com (10.204.65.161) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Wed, 11 Nov 2020 10:23:59 +0100 From: Roberto Sassu To: , CC: , , , , , Roberto Sassu Subject: [PATCH v3 02/11] evm: Load EVM key in ima_load_x509() to avoid appraisal Date: Wed, 11 Nov 2020 10:22:53 +0100 Message-ID: <20201111092302.1589-3-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.27.GIT In-Reply-To: <20201111092302.1589-1-roberto.sassu@huawei.com> References: <20201111092302.1589-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.65.161] X-ClientProxiedBy: lhreml735-chm.china.huawei.com (10.201.108.86) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Public keys do not need to be appraised by IMA as the restriction on the IMA/EVM keyrings ensures that a key can be loaded only if it is signed with a key in the primary or secondary keyring. However, when evm_load_x509() is called, appraisal is already enabled and a valid IMA signature must be added to the EVM key to pass verification. Since the restriction is applied on both IMA and EVM keyrings, it is safe to disable appraisal also when the EVM key is loaded. This patch calls evm_load_x509() inside ima_load_x509() if CONFIG_IMA_LOAD_X509 is defined. Signed-off-by: Roberto Sassu Reviewed-by: Mimi Zohar --- security/integrity/iint.c | 2 ++ security/integrity/ima/ima_init.c | 4 ++++ 2 files changed, 6 insertions(+) diff --git a/security/integrity/iint.c b/security/integrity/iint.c index 1d20003243c3..7d08c31c612f 100644 --- a/security/integrity/iint.c +++ b/security/integrity/iint.c @@ -200,7 +200,9 @@ int integrity_kernel_read(struct file *file, loff_t offset, void __init integrity_load_keys(void) { ima_load_x509(); +#ifndef CONFIG_IMA_LOAD_X509 evm_load_x509(); +#endif } static int __init integrity_fs_init(void) diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 4902fe7bd570..9d29a1680da8 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -106,6 +106,10 @@ void __init ima_load_x509(void) ima_policy_flag &= ~unset_flags; integrity_load_x509(INTEGRITY_KEYRING_IMA, CONFIG_IMA_X509_PATH); + + /* load also EVM key to avoid appraisal */ + evm_load_x509(); + ima_policy_flag |= unset_flags; } #endif