From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fLo8r-0004uO-G3 for kexec@lists.infradead.org; Thu, 24 May 2018 11:10:54 +0000 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w4OB01se063899 for ; Thu, 24 May 2018 07:10:41 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2j5u6hb2ks-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 24 May 2018 07:10:41 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 24 May 2018 12:10:34 +0100 From: Mimi Zohar Subject: [PATCH v3 3/7] ima: based on policy require signed kexec kernel images Date: Thu, 24 May 2018 07:09:32 -0400 In-Reply-To: <1527160176-29269-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1527160176-29269-1-git-send-email-zohar@linux.vnet.ibm.com> Message-Id: <1527160176-29269-4-git-send-email-zohar@linux.vnet.ibm.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: linux-integrity@vger.kernel.org Cc: Andres Rodriguez , Kees Cook , Ard Biesheuvel , Greg Kroah-Hartman , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, David Howells , linux-security-module@vger.kernel.org, Eric Biederman , Mimi Zohar , "Luis R . Rodriguez" 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 Changelog v3: - use switch/case --- security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_main.c | 22 +++++++++++++++++----- security/integrity/ima/ima_policy.c | 2 ++ 3 files changed, 20 insertions(+), 5 deletions(-) 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 eeb7075868db..fbbcc02a1380 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -432,15 +432,27 @@ void ima_post_path_mknod(struct dentry *dentry) */ int ima_read_data(struct file *file, enum kernel_read_file_id read_id) { - bool sig_enforce = is_module_sig_enforced(); + bool sig_enforce; - if (!file && read_id == READING_MODULE) { - if (!sig_enforce && (ima_appraise & IMA_APPRAISE_MODULES) && - (ima_appraise & IMA_APPRAISE_ENFORCE)) { + if ((ima_appraise & IMA_APPRAISE_ENFORCE) != IMA_APPRAISE_ENFORCE) + return 0; + + switch (read_id) { + case READING_MODULE: + sig_enforce = is_module_sig_enforced(); /* appended sig */ + if (!file && !sig_enforce && + (ima_appraise & IMA_APPRAISE_MODULES)) { pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter might help\n"); return -EACCES; /* INTEGRITY_UNKNOWN */ } - return 0; /* We rely on module signature checking */ + break; + case READING_KEXEC_IMAGE: + if (!file && (ima_appraise & IMA_APPRAISE_KEXEC)) { + pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file syscall.\n"); + return -EACCES; /* INTEGRITY_UNKNOWN */ + } + default: + break; } 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; } -- 2.7.5 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec