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 1f6kv4-0008Jf-U2 for kexec@lists.infradead.org; Thu, 12 Apr 2018 22:42:20 +0000 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w3CMdaYn129610 for ; Thu, 12 Apr 2018 18:42:10 -0400 Received: from e06smtp15.uk.ibm.com (e06smtp15.uk.ibm.com [195.75.94.111]) by mx0a-001b2d01.pphosted.com with ESMTP id 2had857m6b-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Thu, 12 Apr 2018 18:42:09 -0400 Received: from localhost by e06smtp15.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 12 Apr 2018 23:42:07 +0100 From: Mimi Zohar Subject: [PATCH 1/3] ima: based on the "secure_boot" policy limit syscalls Date: Thu, 12 Apr 2018 18:41:49 -0400 In-Reply-To: <1523572911-16363-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1523572911-16363-1-git-send-email-zohar@linux.vnet.ibm.com> Message-Id: <1523572911-16363-2-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: David Howells Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Matthew Garrett , linux-security-module@vger.kernel.org, Eric Biederman , linux-integrity@vger.kernel.org, Mimi Zohar The builtin "secure_boot" policy adds IMA appraisal rules requiring kernel modules (finit_module syscall), direct firmware load, kexec kernel image (kexec_file_load syscall), and the IMA policy to be signed, but did not prevent the other syscalls/methods from working. Loading an equivalent custom policy containing these same rules would have prevented the other syscalls/methods from working. This patch refactors the code to load custom policies, defining a new function named ima_appraise_flag(). The new function is called either when loading the builtin "secure_boot" or custom policies. Fixes: 503ceaef8e2e ("ima: define a set of appraisal rules requiring file signatures") Signed-off-by: Mimi Zohar --- security/integrity/ima/ima_policy.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index d89bebf85421..1bdb5bc57568 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -435,6 +435,17 @@ void ima_update_policy_flag(void) ima_policy_flag &= ~IMA_APPRAISE; } +static int ima_appraise_flag(enum ima_hooks func) +{ + if (func == MODULE_CHECK) + return IMA_APPRAISE_MODULES; + else if (func == FIRMWARE_CHECK) + return IMA_APPRAISE_FIRMWARE; + else if (func == POLICY_CHECK) + return IMA_APPRAISE_POLICY; + return 0; +} + /** * ima_init_policy - initialize the default measure rules. * @@ -473,9 +484,12 @@ void __init ima_init_policy(void) * Insert the appraise rules requiring file signatures, prior to * any other appraise rules. */ - for (i = 0; i < secure_boot_entries; i++) + for (i = 0; i < secure_boot_entries; i++) { list_add_tail(&secure_boot_rules[i].list, &ima_default_rules); + temp_ima_appraise |= + ima_appraise_flag(secure_boot_rules[i].func); + } for (i = 0; i < appraise_entries; i++) { list_add_tail(&default_appraise_rules[i].list, @@ -917,12 +931,9 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) } if (!result && (entry->action == UNKNOWN)) result = -EINVAL; - else if (entry->func == MODULE_CHECK) - temp_ima_appraise |= IMA_APPRAISE_MODULES; - else if (entry->func == FIRMWARE_CHECK) - temp_ima_appraise |= IMA_APPRAISE_FIRMWARE; - else if (entry->func == POLICY_CHECK) - temp_ima_appraise |= IMA_APPRAISE_POLICY; + else if (entry->action == APPRAISE) + temp_ima_appraise |= ima_appraise_flag(entry->func); + audit_log_format(ab, "res=%d", !result); audit_log_end(ab); return result; -- 2.7.5 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec