From 1d0ba9c9a0bdbdc22c17a141954911f432a74b39 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Wed, 8 Nov 2017 15:11:32 +0000 Subject: [PATCH] ima: require secure_boot rules in lockdown mode Require the "secure_boot" rules, whether or not it is specified on the boot command line, for both the builtin and custom policies in secure boot lockdown mode. Signed-off-by: Mimi Zohar Signed-off-by: David Howells Gbp-Pq: Topic features/all/lockdown Gbp-Pq: Name 0003-ima-require-secure_boot-rules-in-lockdown-mode.patch --- security/integrity/ima/ima_policy.c | 39 +++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 10 deletions(-) diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index f19f4841a97..61002d1cc00 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -427,14 +427,21 @@ void ima_update_policy_flag(void) */ void __init ima_init_policy(void) { - int i, measure_entries, appraise_entries, secure_boot_entries; + int i; + int measure_entries = 0; + int appraise_entries = 0; + int secure_boot_entries = 0; + bool kernel_locked_down = __kernel_is_locked_down(NULL, false); /* if !ima_policy set entries = 0 so we load NO default rules */ - measure_entries = ima_policy ? ARRAY_SIZE(dont_measure_rules) : 0; - appraise_entries = ima_use_appraise_tcb ? - ARRAY_SIZE(default_appraise_rules) : 0; - secure_boot_entries = ima_use_secure_boot ? - ARRAY_SIZE(secure_boot_rules) : 0; + if (ima_policy) + measure_entries = ARRAY_SIZE(dont_measure_rules); + + if (ima_use_appraise_tcb) + appraise_entries = ARRAY_SIZE(default_appraise_rules); + + if (ima_use_secure_boot || kernel_locked_down) + secure_boot_entries = ARRAY_SIZE(secure_boot_rules); for (i = 0; i < measure_entries; i++) list_add_tail(&dont_measure_rules[i].list, &ima_default_rules); @@ -455,11 +462,23 @@ void __init ima_init_policy(void) /* * Insert the appraise rules requiring file signatures, prior to - * any other appraise rules. + * any other appraise rules. In secure boot lock-down mode, also + * require these appraise rules for custom policies. */ - for (i = 0; i < secure_boot_entries; i++) - list_add_tail(&secure_boot_rules[i].list, - &ima_default_rules); + for (i = 0; i < secure_boot_entries; i++) { + struct ima_rule_entry *entry; + + /* Include for builtin policies */ + list_add_tail(&secure_boot_rules[i].list, &ima_default_rules); + + /* Include for custom policies */ + if (kernel_locked_down) { + entry = kmemdup(&secure_boot_rules[i], sizeof(*entry), + GFP_KERNEL); + if (entry) + list_add_tail(&entry->list, &ima_policy_rules); + } + } for (i = 0; i < appraise_entries; i++) { list_add_tail(&default_appraise_rules[i].list, -- 2.30.2