mirror of
https://github.com/edk2-porting/linux-next.git
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08de59eb14
This reverts commit 4c2c392763
.
Everything in the initramfs should be measured and appraised,
but until the initramfs has extended attribute support, at
least measured.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Cc: Stable Kernel <stable@kernel.org>
711 lines
18 KiB
C
711 lines
18 KiB
C
/*
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* Copyright (C) 2008 IBM Corporation
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* Author: Mimi Zohar <zohar@us.ibm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, version 2 of the License.
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*
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* ima_policy.c
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* - initialize default measure policy rules
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*
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*/
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#include <linux/module.h>
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#include <linux/list.h>
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#include <linux/security.h>
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#include <linux/magic.h>
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#include <linux/parser.h>
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#include <linux/slab.h>
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#include <linux/genhd.h>
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#include "ima.h"
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/* flags definitions */
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#define IMA_FUNC 0x0001
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#define IMA_MASK 0x0002
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#define IMA_FSMAGIC 0x0004
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#define IMA_UID 0x0008
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#define IMA_FOWNER 0x0010
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#define IMA_FSUUID 0x0020
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#define UNKNOWN 0
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#define MEASURE 0x0001 /* same as IMA_MEASURE */
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#define DONT_MEASURE 0x0002
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#define APPRAISE 0x0004 /* same as IMA_APPRAISE */
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#define DONT_APPRAISE 0x0008
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#define AUDIT 0x0040
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#define MAX_LSM_RULES 6
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enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
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LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
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};
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struct ima_rule_entry {
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struct list_head list;
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int action;
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unsigned int flags;
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enum ima_hooks func;
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int mask;
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unsigned long fsmagic;
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u8 fsuuid[16];
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kuid_t uid;
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kuid_t fowner;
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struct {
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void *rule; /* LSM file metadata specific */
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void *args_p; /* audit value */
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int type; /* audit type */
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} lsm[MAX_LSM_RULES];
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};
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/*
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* Without LSM specific knowledge, the default policy can only be
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* written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner
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*/
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/*
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* The minimum rule set to allow for full TCB coverage. Measures all files
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* opened or mmap for exec and everything read by root. Dangerous because
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* normal users can easily run the machine out of memory simply building
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* and running executables.
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*/
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static struct ima_rule_entry default_rules[] = {
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{.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = DEVPTS_SUPER_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = BINFMTFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC},
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{.action = MEASURE,.func = MMAP_CHECK,.mask = MAY_EXEC,
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.flags = IMA_FUNC | IMA_MASK},
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{.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC,
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.flags = IMA_FUNC | IMA_MASK},
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{.action = MEASURE,.func = FILE_CHECK,.mask = MAY_READ,.uid = GLOBAL_ROOT_UID,
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.flags = IMA_FUNC | IMA_MASK | IMA_UID},
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{.action = MEASURE,.func = MODULE_CHECK, .flags = IMA_FUNC},
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};
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static struct ima_rule_entry default_appraise_rules[] = {
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{.action = DONT_APPRAISE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = RAMFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = DEVPTS_SUPER_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = BINFMTFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC},
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{.action = DONT_APPRAISE,.fsmagic = CGROUP_SUPER_MAGIC,.flags = IMA_FSMAGIC},
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{.action = APPRAISE,.fowner = GLOBAL_ROOT_UID,.flags = IMA_FOWNER},
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};
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static LIST_HEAD(ima_default_rules);
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static LIST_HEAD(ima_policy_rules);
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static struct list_head *ima_rules;
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static DEFINE_MUTEX(ima_rules_mutex);
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static bool ima_use_tcb __initdata;
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static int __init default_measure_policy_setup(char *str)
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{
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ima_use_tcb = 1;
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return 1;
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}
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__setup("ima_tcb", default_measure_policy_setup);
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static bool ima_use_appraise_tcb __initdata;
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static int __init default_appraise_policy_setup(char *str)
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{
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ima_use_appraise_tcb = 1;
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return 1;
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}
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__setup("ima_appraise_tcb", default_appraise_policy_setup);
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/*
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* Although the IMA policy does not change, the LSM policy can be
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* reloaded, leaving the IMA LSM based rules referring to the old,
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* stale LSM policy.
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*
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* Update the IMA LSM based rules to reflect the reloaded LSM policy.
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* We assume the rules still exist; and BUG_ON() if they don't.
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*/
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static void ima_lsm_update_rules(void)
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{
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struct ima_rule_entry *entry, *tmp;
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int result;
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int i;
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mutex_lock(&ima_rules_mutex);
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list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
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for (i = 0; i < MAX_LSM_RULES; i++) {
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if (!entry->lsm[i].rule)
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continue;
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result = security_filter_rule_init(entry->lsm[i].type,
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Audit_equal,
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entry->lsm[i].args_p,
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&entry->lsm[i].rule);
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BUG_ON(!entry->lsm[i].rule);
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}
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}
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mutex_unlock(&ima_rules_mutex);
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}
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/**
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* ima_match_rules - determine whether an inode matches the measure rule.
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* @rule: a pointer to a rule
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* @inode: a pointer to an inode
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* @func: LIM hook identifier
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* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
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*
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* Returns true on rule match, false on failure.
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*/
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static bool ima_match_rules(struct ima_rule_entry *rule,
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struct inode *inode, enum ima_hooks func, int mask)
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{
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struct task_struct *tsk = current;
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const struct cred *cred = current_cred();
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int i;
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if ((rule->flags & IMA_FUNC) && rule->func != func)
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return false;
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if ((rule->flags & IMA_MASK) && rule->mask != mask)
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return false;
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if ((rule->flags & IMA_FSMAGIC)
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&& rule->fsmagic != inode->i_sb->s_magic)
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return false;
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if ((rule->flags & IMA_FSUUID) &&
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memcmp(rule->fsuuid, inode->i_sb->s_uuid, sizeof(rule->fsuuid)))
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return false;
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if ((rule->flags & IMA_UID) && !uid_eq(rule->uid, cred->uid))
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return false;
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if ((rule->flags & IMA_FOWNER) && !uid_eq(rule->fowner, inode->i_uid))
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return false;
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for (i = 0; i < MAX_LSM_RULES; i++) {
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int rc = 0;
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u32 osid, sid;
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int retried = 0;
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if (!rule->lsm[i].rule)
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continue;
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retry:
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switch (i) {
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case LSM_OBJ_USER:
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case LSM_OBJ_ROLE:
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case LSM_OBJ_TYPE:
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security_inode_getsecid(inode, &osid);
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rc = security_filter_rule_match(osid,
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rule->lsm[i].type,
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Audit_equal,
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rule->lsm[i].rule,
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NULL);
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break;
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case LSM_SUBJ_USER:
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case LSM_SUBJ_ROLE:
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case LSM_SUBJ_TYPE:
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security_task_getsecid(tsk, &sid);
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rc = security_filter_rule_match(sid,
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rule->lsm[i].type,
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Audit_equal,
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rule->lsm[i].rule,
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NULL);
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default:
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break;
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}
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if ((rc < 0) && (!retried)) {
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retried = 1;
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ima_lsm_update_rules();
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goto retry;
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}
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if (!rc)
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return false;
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}
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return true;
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}
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/*
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* In addition to knowing that we need to appraise the file in general,
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* we need to differentiate between calling hooks, for hook specific rules.
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*/
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static int get_subaction(struct ima_rule_entry *rule, int func)
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{
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if (!(rule->flags & IMA_FUNC))
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return IMA_FILE_APPRAISE;
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switch(func) {
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case MMAP_CHECK:
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return IMA_MMAP_APPRAISE;
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case BPRM_CHECK:
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return IMA_BPRM_APPRAISE;
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case MODULE_CHECK:
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return IMA_MODULE_APPRAISE;
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case FILE_CHECK:
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default:
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return IMA_FILE_APPRAISE;
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}
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}
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/**
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* ima_match_policy - decision based on LSM and other conditions
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* @inode: pointer to an inode for which the policy decision is being made
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* @func: IMA hook identifier
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* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
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*
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* Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
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* conditions.
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*
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* (There is no need for locking when walking the policy list,
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* as elements in the list are never deleted, nor does the list
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* change.)
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*/
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int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
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int flags)
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{
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struct ima_rule_entry *entry;
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int action = 0, actmask = flags | (flags << 1);
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list_for_each_entry(entry, ima_rules, list) {
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if (!(entry->action & actmask))
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continue;
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if (!ima_match_rules(entry, inode, func, mask))
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continue;
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action |= entry->flags & IMA_ACTION_FLAGS;
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action |= entry->action & IMA_DO_MASK;
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if (entry->action & IMA_APPRAISE)
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action |= get_subaction(entry, func);
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if (entry->action & IMA_DO_MASK)
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actmask &= ~(entry->action | entry->action << 1);
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else
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actmask &= ~(entry->action | entry->action >> 1);
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if (!actmask)
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break;
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}
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return action;
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}
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/**
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* ima_init_policy - initialize the default measure rules.
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*
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* ima_rules points to either the ima_default_rules or the
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* the new ima_policy_rules.
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*/
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void __init ima_init_policy(void)
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{
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int i, measure_entries, appraise_entries;
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/* if !ima_use_tcb set entries = 0 so we load NO default rules */
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measure_entries = ima_use_tcb ? ARRAY_SIZE(default_rules) : 0;
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appraise_entries = ima_use_appraise_tcb ?
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ARRAY_SIZE(default_appraise_rules) : 0;
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for (i = 0; i < measure_entries + appraise_entries; i++) {
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if (i < measure_entries)
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list_add_tail(&default_rules[i].list,
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&ima_default_rules);
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else {
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int j = i - measure_entries;
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list_add_tail(&default_appraise_rules[j].list,
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&ima_default_rules);
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}
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}
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ima_rules = &ima_default_rules;
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}
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/**
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* ima_update_policy - update default_rules with new measure rules
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*
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* Called on file .release to update the default rules with a complete new
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* policy. Once updated, the policy is locked, no additional rules can be
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* added to the policy.
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*/
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void ima_update_policy(void)
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{
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const char *op = "policy_update";
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const char *cause = "already exists";
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int result = 1;
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int audit_info = 0;
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if (ima_rules == &ima_default_rules) {
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ima_rules = &ima_policy_rules;
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cause = "complete";
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result = 0;
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}
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integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
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NULL, op, cause, result, audit_info);
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}
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enum {
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Opt_err = -1,
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Opt_measure = 1, Opt_dont_measure,
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Opt_appraise, Opt_dont_appraise,
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Opt_audit,
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Opt_obj_user, Opt_obj_role, Opt_obj_type,
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Opt_subj_user, Opt_subj_role, Opt_subj_type,
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Opt_func, Opt_mask, Opt_fsmagic, Opt_uid, Opt_fowner,
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Opt_appraise_type, Opt_fsuuid
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};
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static match_table_t policy_tokens = {
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{Opt_measure, "measure"},
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{Opt_dont_measure, "dont_measure"},
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{Opt_appraise, "appraise"},
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{Opt_dont_appraise, "dont_appraise"},
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{Opt_audit, "audit"},
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{Opt_obj_user, "obj_user=%s"},
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{Opt_obj_role, "obj_role=%s"},
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{Opt_obj_type, "obj_type=%s"},
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{Opt_subj_user, "subj_user=%s"},
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{Opt_subj_role, "subj_role=%s"},
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{Opt_subj_type, "subj_type=%s"},
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{Opt_func, "func=%s"},
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{Opt_mask, "mask=%s"},
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{Opt_fsmagic, "fsmagic=%s"},
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{Opt_fsuuid, "fsuuid=%s"},
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{Opt_uid, "uid=%s"},
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{Opt_fowner, "fowner=%s"},
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{Opt_appraise_type, "appraise_type=%s"},
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{Opt_err, NULL}
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};
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static int ima_lsm_rule_init(struct ima_rule_entry *entry,
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substring_t *args, int lsm_rule, int audit_type)
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{
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int result;
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if (entry->lsm[lsm_rule].rule)
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return -EINVAL;
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entry->lsm[lsm_rule].args_p = match_strdup(args);
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if (!entry->lsm[lsm_rule].args_p)
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return -ENOMEM;
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entry->lsm[lsm_rule].type = audit_type;
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result = security_filter_rule_init(entry->lsm[lsm_rule].type,
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Audit_equal,
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entry->lsm[lsm_rule].args_p,
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&entry->lsm[lsm_rule].rule);
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if (!entry->lsm[lsm_rule].rule) {
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kfree(entry->lsm[lsm_rule].args_p);
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return -EINVAL;
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}
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return result;
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}
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static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
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{
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audit_log_format(ab, "%s=", key);
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audit_log_untrustedstring(ab, value);
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audit_log_format(ab, " ");
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}
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static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
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{
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struct audit_buffer *ab;
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char *p;
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int result = 0;
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ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
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entry->uid = INVALID_UID;
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entry->fowner = INVALID_UID;
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entry->action = UNKNOWN;
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while ((p = strsep(&rule, " \t")) != NULL) {
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substring_t args[MAX_OPT_ARGS];
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int token;
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unsigned long lnum;
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if (result < 0)
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break;
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if ((*p == '\0') || (*p == ' ') || (*p == '\t'))
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continue;
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token = match_token(p, policy_tokens, args);
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switch (token) {
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case Opt_measure:
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ima_log_string(ab, "action", "measure");
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if (entry->action != UNKNOWN)
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result = -EINVAL;
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entry->action = MEASURE;
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break;
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case Opt_dont_measure:
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ima_log_string(ab, "action", "dont_measure");
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if (entry->action != UNKNOWN)
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result = -EINVAL;
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entry->action = DONT_MEASURE;
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break;
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case Opt_appraise:
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ima_log_string(ab, "action", "appraise");
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if (entry->action != UNKNOWN)
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result = -EINVAL;
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entry->action = APPRAISE;
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break;
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case Opt_dont_appraise:
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ima_log_string(ab, "action", "dont_appraise");
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if (entry->action != UNKNOWN)
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result = -EINVAL;
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entry->action = DONT_APPRAISE;
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break;
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case Opt_audit:
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ima_log_string(ab, "action", "audit");
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if (entry->action != UNKNOWN)
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result = -EINVAL;
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entry->action = AUDIT;
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break;
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case Opt_func:
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ima_log_string(ab, "func", args[0].from);
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|
|
if (entry->func)
|
|
result = -EINVAL;
|
|
|
|
if (strcmp(args[0].from, "FILE_CHECK") == 0)
|
|
entry->func = FILE_CHECK;
|
|
/* PATH_CHECK is for backwards compat */
|
|
else if (strcmp(args[0].from, "PATH_CHECK") == 0)
|
|
entry->func = FILE_CHECK;
|
|
else if (strcmp(args[0].from, "MODULE_CHECK") == 0)
|
|
entry->func = MODULE_CHECK;
|
|
else if ((strcmp(args[0].from, "FILE_MMAP") == 0)
|
|
|| (strcmp(args[0].from, "MMAP_CHECK") == 0))
|
|
entry->func = MMAP_CHECK;
|
|
else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
|
|
entry->func = BPRM_CHECK;
|
|
else
|
|
result = -EINVAL;
|
|
if (!result)
|
|
entry->flags |= IMA_FUNC;
|
|
break;
|
|
case Opt_mask:
|
|
ima_log_string(ab, "mask", args[0].from);
|
|
|
|
if (entry->mask)
|
|
result = -EINVAL;
|
|
|
|
if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
|
|
entry->mask = MAY_EXEC;
|
|
else if (strcmp(args[0].from, "MAY_WRITE") == 0)
|
|
entry->mask = MAY_WRITE;
|
|
else if (strcmp(args[0].from, "MAY_READ") == 0)
|
|
entry->mask = MAY_READ;
|
|
else if (strcmp(args[0].from, "MAY_APPEND") == 0)
|
|
entry->mask = MAY_APPEND;
|
|
else
|
|
result = -EINVAL;
|
|
if (!result)
|
|
entry->flags |= IMA_MASK;
|
|
break;
|
|
case Opt_fsmagic:
|
|
ima_log_string(ab, "fsmagic", args[0].from);
|
|
|
|
if (entry->fsmagic) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(args[0].from, 16,
|
|
&entry->fsmagic);
|
|
if (!result)
|
|
entry->flags |= IMA_FSMAGIC;
|
|
break;
|
|
case Opt_fsuuid:
|
|
ima_log_string(ab, "fsuuid", args[0].from);
|
|
|
|
if (memchr_inv(entry->fsuuid, 0x00,
|
|
sizeof(entry->fsuuid))) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = blk_part_pack_uuid(args[0].from,
|
|
entry->fsuuid);
|
|
if (!result)
|
|
entry->flags |= IMA_FSUUID;
|
|
break;
|
|
case Opt_uid:
|
|
ima_log_string(ab, "uid", args[0].from);
|
|
|
|
if (uid_valid(entry->uid)) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(args[0].from, 10, &lnum);
|
|
if (!result) {
|
|
entry->uid = make_kuid(current_user_ns(), (uid_t)lnum);
|
|
if (!uid_valid(entry->uid) || (((uid_t)lnum) != lnum))
|
|
result = -EINVAL;
|
|
else
|
|
entry->flags |= IMA_UID;
|
|
}
|
|
break;
|
|
case Opt_fowner:
|
|
ima_log_string(ab, "fowner", args[0].from);
|
|
|
|
if (uid_valid(entry->fowner)) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
result = strict_strtoul(args[0].from, 10, &lnum);
|
|
if (!result) {
|
|
entry->fowner = make_kuid(current_user_ns(), (uid_t)lnum);
|
|
if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum))
|
|
result = -EINVAL;
|
|
else
|
|
entry->flags |= IMA_FOWNER;
|
|
}
|
|
break;
|
|
case Opt_obj_user:
|
|
ima_log_string(ab, "obj_user", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_OBJ_USER,
|
|
AUDIT_OBJ_USER);
|
|
break;
|
|
case Opt_obj_role:
|
|
ima_log_string(ab, "obj_role", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_OBJ_ROLE,
|
|
AUDIT_OBJ_ROLE);
|
|
break;
|
|
case Opt_obj_type:
|
|
ima_log_string(ab, "obj_type", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_OBJ_TYPE,
|
|
AUDIT_OBJ_TYPE);
|
|
break;
|
|
case Opt_subj_user:
|
|
ima_log_string(ab, "subj_user", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_SUBJ_USER,
|
|
AUDIT_SUBJ_USER);
|
|
break;
|
|
case Opt_subj_role:
|
|
ima_log_string(ab, "subj_role", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_SUBJ_ROLE,
|
|
AUDIT_SUBJ_ROLE);
|
|
break;
|
|
case Opt_subj_type:
|
|
ima_log_string(ab, "subj_type", args[0].from);
|
|
result = ima_lsm_rule_init(entry, args,
|
|
LSM_SUBJ_TYPE,
|
|
AUDIT_SUBJ_TYPE);
|
|
break;
|
|
case Opt_appraise_type:
|
|
if (entry->action != APPRAISE) {
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
ima_log_string(ab, "appraise_type", args[0].from);
|
|
if ((strcmp(args[0].from, "imasig")) == 0)
|
|
entry->flags |= IMA_DIGSIG_REQUIRED;
|
|
else
|
|
result = -EINVAL;
|
|
break;
|
|
case Opt_err:
|
|
ima_log_string(ab, "UNKNOWN", p);
|
|
result = -EINVAL;
|
|
break;
|
|
}
|
|
}
|
|
if (!result && (entry->action == UNKNOWN))
|
|
result = -EINVAL;
|
|
else if (entry->func == MODULE_CHECK)
|
|
ima_appraise |= IMA_APPRAISE_MODULES;
|
|
audit_log_format(ab, "res=%d", !result);
|
|
audit_log_end(ab);
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* ima_parse_add_rule - add a rule to ima_policy_rules
|
|
* @rule - ima measurement policy rule
|
|
*
|
|
* Uses a mutex to protect the policy list from multiple concurrent writers.
|
|
* Returns the length of the rule parsed, an error code on failure
|
|
*/
|
|
ssize_t ima_parse_add_rule(char *rule)
|
|
{
|
|
const char *op = "update_policy";
|
|
char *p;
|
|
struct ima_rule_entry *entry;
|
|
ssize_t result, len;
|
|
int audit_info = 0;
|
|
|
|
/* Prevent installed policy from changing */
|
|
if (ima_rules != &ima_default_rules) {
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
|
|
NULL, op, "already exists",
|
|
-EACCES, audit_info);
|
|
return -EACCES;
|
|
}
|
|
|
|
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
|
|
if (!entry) {
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
|
|
NULL, op, "-ENOMEM", -ENOMEM, audit_info);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
INIT_LIST_HEAD(&entry->list);
|
|
|
|
p = strsep(&rule, "\n");
|
|
len = strlen(p) + 1;
|
|
|
|
if (*p == '#') {
|
|
kfree(entry);
|
|
return len;
|
|
}
|
|
|
|
result = ima_parse_rule(p, entry);
|
|
if (result) {
|
|
kfree(entry);
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
|
|
NULL, op, "invalid policy", result,
|
|
audit_info);
|
|
return result;
|
|
}
|
|
|
|
mutex_lock(&ima_rules_mutex);
|
|
list_add_tail(&entry->list, &ima_policy_rules);
|
|
mutex_unlock(&ima_rules_mutex);
|
|
|
|
return len;
|
|
}
|
|
|
|
/* ima_delete_rules called to cleanup invalid policy */
|
|
void ima_delete_rules(void)
|
|
{
|
|
struct ima_rule_entry *entry, *tmp;
|
|
int i;
|
|
|
|
mutex_lock(&ima_rules_mutex);
|
|
list_for_each_entry_safe(entry, tmp, &ima_policy_rules, list) {
|
|
for (i = 0; i < MAX_LSM_RULES; i++)
|
|
kfree(entry->lsm[i].args_p);
|
|
|
|
list_del(&entry->list);
|
|
kfree(entry);
|
|
}
|
|
mutex_unlock(&ima_rules_mutex);
|
|
}
|