From patchwork Thu May 17 14:48:46 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mimi Zohar X-Patchwork-Id: 10406919 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DBFE960353 for ; Thu, 17 May 2018 14:51:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CB13528653 for ; Thu, 17 May 2018 14:51:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C8758286F5; Thu, 17 May 2018 14:51:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6AAE228843 for ; Thu, 17 May 2018 14:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751644AbeEQOvC (ORCPT ); Thu, 17 May 2018 10:51:02 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:36772 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752514AbeEQOts (ORCPT ); Thu, 17 May 2018 10:49:48 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w4HEjUNF145711 for ; Thu, 17 May 2018 10:49:48 -0400 Received: from e06smtp13.uk.ibm.com (e06smtp13.uk.ibm.com [195.75.94.109]) by mx0b-001b2d01.pphosted.com with ESMTP id 2j199r832v-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 17 May 2018 10:49:47 -0400 Received: from localhost by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 17 May 2018 15:49:41 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w4HEnf9Z10682684; Thu, 17 May 2018 14:49:41 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B16984C04E; Thu, 17 May 2018 15:41:29 +0100 (BST) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 188384C044; Thu, 17 May 2018 15:41:28 +0100 (BST) Received: from localhost.ibm.com (unknown [9.80.108.64]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 17 May 2018 15:41:27 +0100 (BST) From: Mimi Zohar To: linux-integrity@vger.kernel.org Cc: Mimi Zohar , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, David Howells , "Luis R . Rodriguez" , Eric Biederman , kexec@lists.infradead.org, Andres Rodriguez , Greg Kroah-Hartman , Ard Biesheuvel , Kees Cook Subject: [PATCH v2 5/9] ima: based on policy require signed kexec kernel images Date: Thu, 17 May 2018 10:48:46 -0400 X-Mailer: git-send-email 2.7.5 In-Reply-To: <1526568530-9144-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1526568530-9144-1-git-send-email-zohar@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18051714-0012-0000-0000-000005D7A702 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18051714-0013-0000-0000-00001954D35A Message-Id: <1526568530-9144-6-git-send-email-zohar@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-05-17_08:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1805170137 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The original kexec_load syscall can not verify file signatures. This patch differentiates between the kexec_load and kexec_file_load syscalls. Signed-off-by: Mimi Zohar Cc: Eric Biederman Cc: Luis R. Rodriguez Cc: Kees Cook Cc: David Howells --- security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_main.c | 9 +++++++++ security/integrity/ima/ima_policy.c | 2 ++ 3 files changed, 12 insertions(+) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 354bb5716ce3..78c15264b17b 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -232,6 +232,7 @@ int ima_policy_show(struct seq_file *m, void *v); #define IMA_APPRAISE_MODULES 0x08 #define IMA_APPRAISE_FIRMWARE 0x10 #define IMA_APPRAISE_POLICY 0x20 +#define IMA_APPRAISE_KEXEC 0x40 #ifdef CONFIG_IMA_APPRAISE int ima_appraise_measurement(enum ima_hooks func, diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 83f84928ad76..7e1a127f18fe 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -442,6 +442,15 @@ int ima_read_file(struct file *file, enum kernel_read_file_id read_id) } return 0; /* We rely on module signature checking */ } + + if (!file && read_id == READING_KEXEC_IMAGE) { + if ((ima_appraise & IMA_APPRAISE_KEXEC) && + (ima_appraise & IMA_APPRAISE_ENFORCE)) { + pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file syscall.\n"); + return -EACCES; /* INTEGRITY_UNKNOWN */ + } + return 0; + } return 0; } diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 8bbc18eb07eb..c27f6993b07a 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -448,6 +448,8 @@ static int ima_appraise_flag(enum ima_hooks func) return IMA_APPRAISE_FIRMWARE; else if (func == POLICY_CHECK) return IMA_APPRAISE_POLICY; + else if (func == KEXEC_KERNEL_CHECK) + return IMA_APPRAISE_KEXEC; return 0; }