@@ -11,6 +11,7 @@
#include <linux/fs.h>
#include <linux/security.h>
#include <linux/kexec.h>
+#include <linux/user_namespace.h>
#include <crypto/hash_info.h>
struct linux_binprm;
@@ -1269,6 +1269,20 @@ config NET_NS
Allow user space to create what appear to be multiple instances
of the network stack.
+config IMA_NS
+ bool "IMA namespace"
+ depends on USER_NS
+ depends on IMA
+ select IMA_READ_POLICY
+ default n
+ help
+ Allow the creation of an IMA namespace for each user namespace.
+ Namespaced IMA enables having IMA features work separately
+ in each IMA namespace.
+ Currently, only the audit status flags are stored in the namespace,
+ which allows the same file to be audited each time it is accessed
+ in a new namespace.
+
endif # NAMESPACES
config CHECKPOINT_RESTORE
@@ -21,6 +21,7 @@
#include <linux/fs_struct.h>
#include <linux/bsearch.h>
#include <linux/sort.h>
+#include <linux/ima.h>
static struct kmem_cache *user_ns_cachep __read_mostly;
static DEFINE_MUTEX(userns_state_mutex);
@@ -213,6 +214,7 @@ static void free_user_ns(struct work_struct *work)
kfree(ns->projid_map.forward);
kfree(ns->projid_map.reverse);
}
+ free_ima_ns(ns);
retire_userns_sysctls(ns);
key_free_user_ns(ns);
ns_free_inum(&ns->ns);
@@ -341,10 +341,10 @@ int ima_match_policy(struct ima_namespace *ns,
int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
const char *func_data, unsigned int *allowed_algos);
-void ima_init_policy(struct ima_namespace *ns);
+void ima_init_policy(struct user_namespace *user_ns);
void ima_update_policy(struct ima_namespace *ns);
void ima_update_policy_flags(struct ima_namespace *ns);
-ssize_t ima_parse_add_rule(struct ima_namespace *ns, char *rule);
+ssize_t ima_parse_add_rule(struct user_namespace *user_ns, char *rule);
void ima_delete_rules(struct ima_namespace *ns);
int ima_check_policy(struct ima_namespace *ns);
void ima_free_policy_rules(struct ima_namespace *ns);
@@ -545,32 +545,72 @@ struct user_namespace *ima_user_ns_from_file(const struct file *filp)
return file_sb_user_ns(filp);
}
+#ifdef CONFIG_IMA_NS
+
static inline struct ima_namespace
*ima_ns_from_user_ns(struct user_namespace *user_ns)
{
- if (user_ns == &init_user_ns)
- return &init_ima_ns;
- return NULL;
+ /* Pairs with smp_store_releases() in user_ns_set_ima_ns(). */
+ return smp_load_acquire(&user_ns->ima_ns);
}
-#ifdef CONFIG_IMA_NS
+static inline void user_ns_set_ima_ns(struct user_namespace *user_ns,
+ struct ima_namespace *ns)
+{
+ /* Pairs with smp_load_acquire() in ima_ns_from_user_ns() */
+ smp_store_release(&user_ns->ima_ns, ns);
+}
+
+static inline struct ima_namespace *get_current_ns(void)
+{
+ return ima_ns_from_user_ns(current_user_ns());
+}
struct ima_namespace *create_ima_ns(void);
+void ima_free_ima_ns(struct ima_namespace *ns);
+
struct ns_status *ima_get_ns_status(struct ima_namespace *ns,
struct inode *inode,
struct integrity_iint_cache *iint);
void ima_free_ns_status_tree(struct ima_namespace *ns);
+static inline struct ima_namespace *ima_ns_from_file(const struct file *filp)
+{
+ struct user_namespace *user_ns = ima_user_ns_from_file(filp);
+
+ return ima_ns_from_user_ns(user_ns);
+}
+
#else
+static inline struct ima_namespace
+*ima_ns_from_user_ns(struct user_namespace *user_ns)
+{
+ if (user_ns == &init_user_ns)
+ return &init_ima_ns;
+ return NULL;
+}
+
+static inline void user_ns_set_ima_ns(struct user_namespace *user_ns,
+ struct ima_namespace *ns)
+{
+}
+
+static inline struct ima_namespace *get_current_ns(void)
+{
+ return &init_ima_ns;
+}
+
static inline struct ima_namespace *create_ima_ns(void)
{
WARN(1, "Cannot create an IMA namespace\n");
return ERR_PTR(-EFAULT);
}
+static inline void ima_free_ima_ns(struct ima_namespace *ns) {}
+
static inline struct ns_status *ima_get_ns_status
(struct ima_namespace *ns,
struct inode *inode,
@@ -586,6 +626,11 @@ static inline struct ns_status *ima_get_ns_status
return ns_status;
}
+static inline struct ima_namespace *ima_ns_from_file(const struct file *filp)
+{
+ return &init_ima_ns;
+}
+
#endif /* CONFIG_IMA_NS */
#endif /* __LINUX_IMA_H */
@@ -76,6 +76,9 @@ int ima_must_appraise(struct ima_namespace *ns,
{
u32 secid;
+ if (ns != &init_ima_ns)
+ return 0;
+
if (!ima_appraise)
return 0;
@@ -600,6 +603,8 @@ int ima_appraise_measurement(enum ima_hooks func,
/*
* ima_update_xattr - update 'security.ima' hash value
+ *
+ * Only a namespace with a hash policy would ever update the file.
*/
void ima_update_xattr(struct ima_namespace *ns,
struct integrity_iint_cache *iint, struct file *file)
@@ -607,6 +612,9 @@ void ima_update_xattr(struct ima_namespace *ns,
struct dentry *dentry = file_dentry(file);
int rc = 0;
+ if (!ns_is_active(ns) || !(ns->ima_policy_flag & IMA_HASH))
+ return;
+
/* do not collect and update hash for digital signatures */
if (test_bit(IMA_DIGSIG, &iint->atomic_flags))
return;
@@ -30,9 +30,13 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
const void *payload, size_t payload_len,
unsigned long flags, bool create)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
bool queued = false;
+ /* only handle key if related to init_ima_ns */
+ if (ns != &init_ima_ns)
+ return;
+
/* Only asymmetric keys are handled by this hook. */
if (key->type != &key_type_asymmetric)
return;
@@ -49,7 +49,10 @@ static ssize_t ima_show_htable_violations(struct file *filp,
char __user *buf,
size_t count, loff_t *ppos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(filp);
+
+ if (!ns_is_active(ns))
+ return -EACCES;
return ima_show_htable_value(buf, count, ppos,
&ns->ima_htable.violations);
@@ -64,7 +67,10 @@ static ssize_t ima_show_measurements_count(struct file *filp,
char __user *buf,
size_t count, loff_t *ppos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(filp);
+
+ if (!ns_is_active(ns))
+ return -EACCES;
return ima_show_htable_value(buf, count, ppos, &ns->ima_htable.len);
}
@@ -77,7 +83,7 @@ static const struct file_operations ima_measurements_count_ops = {
/* returns pointer to hlist_node */
static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(m->file);
loff_t l = *pos;
struct ima_queue_entry *qe;
@@ -95,7 +101,7 @@ static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(m->file);
struct ima_queue_entry *qe = v;
/* lock protects when reading beyond last element
@@ -198,6 +204,11 @@ static const struct seq_operations ima_measurments_seqops = {
static int ima_measurements_open(struct inode *inode, struct file *file)
{
+ struct ima_namespace *ns = ima_ns_from_file(file);
+
+ if (!ns_is_active(ns))
+ return -EACCES;
+
return seq_open(file, &ima_measurments_seqops);
}
@@ -264,6 +275,11 @@ static const struct seq_operations ima_ascii_measurements_seqops = {
static int ima_ascii_measurements_open(struct inode *inode, struct file *file)
{
+ struct ima_namespace *ns = ima_ns_from_file(file);
+
+ if (!ns_is_active(ns))
+ return -EACCES;
+
return seq_open(file, &ima_ascii_measurements_seqops);
}
@@ -274,7 +290,7 @@ static const struct file_operations ima_ascii_measurements_ops = {
.release = seq_release,
};
-static ssize_t ima_read_policy(struct ima_namespace *ns, char *path)
+static ssize_t ima_read_policy(struct user_namespace *user_ns, char *path)
{
void *data = NULL;
char *datap;
@@ -299,7 +315,7 @@ static ssize_t ima_read_policy(struct ima_namespace *ns, char *path)
datap = data;
while (size > 0 && (p = strsep(&datap, "\n"))) {
pr_debug("rule: %s\n", p);
- rc = ima_parse_add_rule(ns, p);
+ rc = ima_parse_add_rule(user_ns, p);
if (rc < 0)
break;
size -= rc;
@@ -317,10 +333,14 @@ static ssize_t ima_read_policy(struct ima_namespace *ns, char *path)
static ssize_t ima_write_policy(struct file *file, const char __user *buf,
size_t datalen, loff_t *ppos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct user_namespace *user_ns = ima_user_ns_from_file(file);
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
char *data;
ssize_t result;
+ if (!ns_is_active(ns))
+ return -EACCES;
+
if (datalen >= PAGE_SIZE)
datalen = PAGE_SIZE - 1;
@@ -340,15 +360,16 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf,
goto out_free;
if (data[0] == '/') {
- result = ima_read_policy(ns, data);
- } else if (ima_appraise & IMA_APPRAISE_POLICY) {
+ result = ima_read_policy(user_ns, data);
+ } else if (ns == &init_ima_ns &&
+ (ima_appraise & IMA_APPRAISE_POLICY)) {
pr_err("signed policy file (specified as an absolute pathname) required\n");
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
"policy_update", "signed policy required",
1, 0);
result = -EACCES;
} else {
- result = ima_parse_add_rule(ns, data);
+ result = ima_parse_add_rule(user_ns, data);
}
mutex_unlock(&ns->ima_write_mutex);
out_free:
@@ -381,7 +402,10 @@ static int ima_open_policy(struct inode *inode, struct file *filp)
#ifdef CONFIG_IMA_READ_POLICY
struct user_namespace *user_ns = ima_user_ns_from_file(filp);
#endif
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(filp);
+
+ if (!ns_is_active(ns))
+ return -EACCES;
if (!(filp->f_flags & O_WRONLY)) {
#ifndef CONFIG_IMA_READ_POLICY
@@ -408,7 +432,7 @@ static int ima_open_policy(struct inode *inode, struct file *filp)
*/
static int ima_release_policy(struct inode *inode, struct file *file)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(file);
const char *cause = ns->valid_policy ? "completed" : "failed";
if ((file->f_flags & O_ACCMODE) == O_RDONLY)
@@ -419,11 +443,12 @@ static int ima_release_policy(struct inode *inode, struct file *file)
ns->valid_policy = 0;
}
- pr_info("policy update %s\n", cause);
- if (ns == &init_ima_ns)
+ if (ns == &init_ima_ns) {
+ pr_info("policy update %s\n", cause);
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
"policy_update", cause, !ns->valid_policy,
0);
+ }
if (!ns->valid_policy) {
ima_delete_rules(ns);
@@ -457,7 +482,7 @@ static ssize_t ima_show_active(struct file *filp,
char __user *buf,
size_t count, loff_t *ppos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(filp);
char tmpbuf[2];
ssize_t len;
@@ -470,7 +495,7 @@ static ssize_t ima_write_active(struct file *filp,
const char __user *buf,
size_t count, loff_t *ppos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(filp);
unsigned int active;
char *kbuf;
int err;
@@ -494,7 +519,9 @@ static ssize_t ima_write_active(struct file *filp,
if (active != 1)
return -EINVAL;
- set_bit(IMA_NS_ACTIVE, &ns->ima_ns_flags);
+ err = ima_init_namespace(ns);
+ if (err)
+ return -EINVAL;
return count;
}
@@ -517,11 +544,28 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root)
struct dentry *active = NULL;
int ret;
+ /*
+ * While multiple superblocks can exist they are keyed by userns in
+ * s_fs_info for securityfs. The first time a userns mounts a
+ * securityfs instance we lazily allocate the ima_namespace for the
+ * userns since that's the only way a userns can meaningfully use ima.
+ * The vfs ensures we're the only one to call fill_super() and hence
+ * ima_fs_ns_init(), so we don't need any memory barriers here, i.e.
+ * user_ns->ima_ns can't change while we're in here.
+ */
+ if (!ns) {
+ ns = create_ima_ns();
+ if (IS_ERR(ns))
+ return PTR_ERR(ns);
+ }
+
/* FIXME: update when evm and integrity are namespaced */
if (user_ns != &init_user_ns) {
int_dir = securityfs_create_dir("integrity", root);
- if (IS_ERR(int_dir))
- return PTR_ERR(int_dir);
+ if (IS_ERR(int_dir)) {
+ ret = PTR_ERR(int_dir);
+ goto free_ns;
+ }
} else {
int_dir = integrity_dir;
}
@@ -596,6 +640,9 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root)
}
}
+ if (!ima_ns_from_user_ns(user_ns))
+ user_ns_set_ima_ns(user_ns, ns);
+
return 0;
out:
securityfs_remove(active);
@@ -609,6 +656,10 @@ int ima_fs_ns_init(struct user_namespace *user_ns, struct dentry *root)
if (user_ns != &init_user_ns)
securityfs_remove(int_dir);
+free_ns:
+ if (!ima_ns_from_user_ns(user_ns))
+ ima_free_ima_ns(ns);
+
return ret;
}
@@ -147,7 +147,7 @@ int __init ima_init(void)
if (rc != 0)
return rc;
- ima_init_policy(&init_ima_ns);
+ ima_init_policy(&init_user_ns);
rc = ima_fs_init();
if (rc != 0)
@@ -46,6 +46,8 @@ int ima_init_namespace(struct ima_namespace *ns)
goto err_destroy_cache;
}
+ set_bit(IMA_NS_ACTIVE, &ns->ima_ns_flags);
+
return 0;
err_destroy_cache:
@@ -211,11 +211,11 @@ static void ima_check_last_writer(struct ima_namespace *ns,
*/
void ima_file_free(struct file *file)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
struct inode *inode = file_inode(file);
struct integrity_iint_cache *iint;
- if (!ns->ima_policy_flag || !S_ISREG(inode->i_mode))
+ if (!S_ISREG(inode->i_mode))
return;
iint = integrity_iint_find(inode);
@@ -511,7 +511,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
*/
int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
struct ima_template_desc *template = NULL;
struct file *file;
char filename[NAME_MAX];
@@ -524,7 +524,8 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
int pcr;
/* Is mprotect making an mmap'ed file executable? */
- if (!(ns->ima_policy_flag & IMA_APPRAISE) || !vma->vm_file ||
+ if (!ns_is_active(ns) ||
+ !(ns->ima_policy_flag & IMA_APPRAISE) || !vma->vm_file ||
!(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))
return 0;
@@ -684,9 +685,9 @@ static int __ima_inode_hash(struct ima_namespace *ns, struct inode *inode,
*/
int ima_file_hash(struct file *file, char *buf, size_t buf_size)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
- if (!file)
+ if (!ns_is_active(ns) || !file)
return -EINVAL;
return __ima_inode_hash(ns, file_inode(file), file, buf, buf_size);
@@ -713,9 +714,9 @@ EXPORT_SYMBOL_GPL(ima_file_hash);
*/
int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
- if (!inode)
+ if (!ns_is_active(ns) || !inode)
return -EINVAL;
return __ima_inode_hash(ns, inode, NULL, buf, buf_size);
@@ -734,11 +735,12 @@ EXPORT_SYMBOL_GPL(ima_inode_hash);
void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
struct inode *inode)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
struct integrity_iint_cache *iint;
int must_appraise;
- if (!ns->ima_policy_flag || !S_ISREG(inode->i_mode))
+ if (!ns_is_active(ns) || !ns->ima_policy_flag ||
+ !S_ISREG(inode->i_mode))
return;
must_appraise = ima_must_appraise(ns, mnt_userns, inode, MAY_ACCESS,
@@ -767,12 +769,13 @@ void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
void ima_post_path_mknod(struct user_namespace *mnt_userns,
struct dentry *dentry)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
struct integrity_iint_cache *iint;
struct inode *inode = dentry->d_inode;
int must_appraise;
- if (!ns->ima_policy_flag || !S_ISREG(inode->i_mode))
+ if (!ns_is_active(ns) || !ns->ima_policy_flag ||
+ !S_ISREG(inode->i_mode))
return;
must_appraise = ima_must_appraise(ns, mnt_userns, inode, MAY_ACCESS,
@@ -891,8 +894,12 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
*/
int ima_load_data(enum kernel_load_data_id id, bool contents)
{
+ struct ima_namespace *ns = get_current_ns();
bool ima_enforce, sig_enforce;
+ if (ns != &init_ima_ns)
+ return 0;
+
ima_enforce =
(ima_appraise & IMA_APPRAISE_ENFORCE) == IMA_APPRAISE_ENFORCE;
@@ -1097,10 +1104,10 @@ int process_buffer_measurement(struct ima_namespace *ns,
*/
void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
struct fd f;
- if (!buf || !size)
+ if (!ns_is_active(ns) || !buf || !size)
return;
f = fdget(kernel_fd);
@@ -1138,7 +1145,10 @@ int ima_measure_critical_data(const char *event_label,
const void *buf, size_t buf_len,
bool hash, u8 *digest, size_t digest_len)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = get_current_ns();
+
+ if (!ns_is_active(ns))
+ return -EINVAL;
if (!event_name || !event_label || !buf || !buf_len)
return -ENOPARAM;
@@ -26,22 +26,29 @@ struct ima_namespace *create_ima_ns(void)
/* destroy_ima_ns() must only be called after ima_init_namespace() was called */
static void destroy_ima_ns(struct ima_namespace *ns)
{
+ clear_bit(IMA_NS_ACTIVE, &ns->ima_ns_flags);
unregister_blocking_lsm_notifier(&ns->ima_lsm_policy_notifier);
kfree(ns->arch_policy_entry);
ima_free_policy_rules(ns);
ima_free_ns_status_tree(ns);
}
-void free_ima_ns(struct user_namespace *user_ns)
+void ima_free_ima_ns(struct ima_namespace *ns)
{
- struct ima_namespace *ns = user_ns->ima_ns;
-
if (!ns || WARN_ON(ns == &init_ima_ns))
return;
- destroy_ima_ns(ns);
+ if (ns_is_active(ns))
+ destroy_ima_ns(ns);
kmem_cache_free(imans_cachep, ns);
+}
+
+void free_ima_ns(struct user_namespace *user_ns)
+{
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
+
+ ima_free_ima_ns(ns);
user_ns->ima_ns = NULL;
}
@@ -507,8 +507,8 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
return NOTIFY_DONE;
ns = container_of(nb, struct ima_namespace, ima_lsm_policy_notifier);
-
- set_bit(IMA_NS_LSM_UPDATE_RULES, &ns->ima_ns_flags);
+ if (ns_is_active(ns))
+ set_bit(IMA_NS_LSM_UPDATE_RULES, &ns->ima_ns_flags);
return NOTIFY_OK;
}
@@ -907,11 +907,12 @@ static void add_rules(struct ima_namespace *ns,
}
}
-static int ima_parse_rule(struct ima_namespace *ns,
+static int ima_parse_rule(struct user_namespace *user_ns,
char *rule, struct ima_rule_entry *entry);
-static int __init ima_init_arch_policy(struct ima_namespace *ns)
+static int __init ima_init_arch_policy(struct user_namespace *user_ns)
{
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
const char * const *arch_rules;
const char * const *rules;
int arch_entries = 0;
@@ -939,7 +940,8 @@ static int __init ima_init_arch_policy(struct ima_namespace *ns)
result = strscpy(rule, *rules, sizeof(rule));
INIT_LIST_HEAD(&ns->arch_policy_entry[i].list);
- result = ima_parse_rule(ns, rule, &ns->arch_policy_entry[i]);
+ result = ima_parse_rule(user_ns, rule,
+ &ns->arch_policy_entry[i]);
if (result) {
pr_warn("Skipping unknown architecture policy rule: %s\n",
rule);
@@ -954,11 +956,12 @@ static int __init ima_init_arch_policy(struct ima_namespace *ns)
/**
* ima_init_policy - initialize the default measure rules.
- * @ns: IMA namespace to which the policy belongs to
+ * @user_ns: User namespace pointig to IMA namespace to which the policy belongs
* ima_rules points to either the ima_default_rules or the new ima_policy_rules.
*/
-void __init ima_init_policy(struct ima_namespace *ns)
+void __init ima_init_policy(struct user_namespace *user_ns)
{
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
int build_appraise_entries, arch_entries;
/* if !ima_policy, we load NO default rules */
@@ -988,7 +991,7 @@ void __init ima_init_policy(struct ima_namespace *ns)
* and custom policies, prior to other appraise rules.
* (Highest priority)
*/
- arch_entries = ima_init_arch_policy(ns);
+ arch_entries = ima_init_arch_policy(user_ns);
if (!arch_entries)
pr_info("No architecture policies found\n");
else
@@ -1439,9 +1442,22 @@ static unsigned int ima_parse_appraise_algos(char *arg)
return res;
}
-static int ima_parse_rule(struct ima_namespace *ns,
+/*
+ * Either host root with CAP_AUDIT_WRITE in current user namespace or
+ * root with CAP_AUDIT_WRITE on the host entering a namespace may set
+ * audit rules inside a namespace.
+ */
+static bool may_set_audit_rule_in_ns(kuid_t uid, struct user_namespace *user_ns)
+{
+ return (uid_eq(uid, GLOBAL_ROOT_UID) &&
+ ns_capable(user_ns, CAP_AUDIT_WRITE)) ||
+ capable(CAP_AUDIT_WRITE);
+}
+
+static int ima_parse_rule(struct user_namespace *user_ns,
char *rule, struct ima_rule_entry *entry)
{
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
struct audit_buffer *ab = NULL;
char *from;
char *p;
@@ -1692,7 +1708,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
result = kstrtoul(args[0].from, 10, &lnum);
if (!result) {
- entry->uid = make_kuid(current_user_ns(),
+ entry->uid = make_kuid(user_ns,
(uid_t) lnum);
if (!uid_valid(entry->uid) ||
(uid_t)lnum != lnum)
@@ -1727,7 +1743,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
result = kstrtoul(args[0].from, 10, &lnum);
if (!result) {
- entry->gid = make_kgid(current_user_ns(),
+ entry->gid = make_kgid(user_ns,
(gid_t)lnum);
if (!gid_valid(entry->gid) ||
(((gid_t)lnum) != lnum))
@@ -1754,7 +1770,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
result = kstrtoul(args[0].from, 10, &lnum);
if (!result) {
- entry->fowner = make_kuid(current_user_ns(),
+ entry->fowner = make_kuid(user_ns,
(uid_t)lnum);
if (!uid_valid(entry->fowner) ||
(((uid_t)lnum) != lnum))
@@ -1780,7 +1796,7 @@ static int ima_parse_rule(struct ima_namespace *ns,
result = kstrtoul(args[0].from, 10, &lnum);
if (!result) {
- entry->fgroup = make_kgid(current_user_ns(),
+ entry->fgroup = make_kgid(user_ns,
(gid_t)lnum);
if (!gid_valid(entry->fgroup) ||
(((gid_t)lnum) != lnum))
@@ -1935,6 +1951,12 @@ static int ima_parse_rule(struct ima_namespace *ns,
case HASH:
result = -EINVAL;
goto err_audit;
+ case AUDIT:
+ if (!may_set_audit_rule_in_ns(current_uid(),
+ user_ns)) {
+ result = -EPERM;
+ goto err_audit;
+ }
}
}
}
@@ -1966,14 +1988,15 @@ static int ima_parse_rule(struct ima_namespace *ns,
/**
* ima_parse_add_rule - add a rule to ima_policy_rules
- * @ns: IMA namespace that has the policy
+ * @user_ns: User namespace referencing the IMA namespace that has the policy
* @rule - ima measurement policy rule
*
* Avoid locking by allowing just one writer at a time in ima_write_policy()
* Returns the length of the rule parsed, an error code on failure
*/
-ssize_t ima_parse_add_rule(struct ima_namespace *ns, char *rule)
+ssize_t ima_parse_add_rule(struct user_namespace *user_ns, char *rule)
{
+ struct ima_namespace *ns = ima_ns_from_user_ns(user_ns);
static const char op[] = "update_policy";
char *p;
struct ima_rule_entry *entry;
@@ -1998,7 +2021,7 @@ ssize_t ima_parse_add_rule(struct ima_namespace *ns, char *rule)
INIT_LIST_HEAD(&entry->list);
- result = ima_parse_rule(ns, p, entry);
+ result = ima_parse_rule(user_ns, p, entry);
if (result) {
ima_free_rule(entry);
if (ns == &init_ima_ns)
@@ -2024,7 +2047,9 @@ void ima_delete_rules(struct ima_namespace *ns)
{
struct ima_rule_entry *entry, *tmp;
- temp_ima_appraise = 0;
+ if (ns == &init_ima_ns)
+ temp_ima_appraise = 0;
+
list_for_each_entry_safe(entry, tmp, &ns->ima_temp_rules, list) {
list_del(&entry->list);
ima_free_rule(entry);
@@ -2065,7 +2090,7 @@ static const char *const mask_tokens[] = {
void *ima_policy_start(struct seq_file *m, loff_t *pos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(m->file);
loff_t l = *pos;
struct ima_rule_entry *entry;
struct list_head *ima_rules_tmp;
@@ -2086,7 +2111,7 @@ void *ima_policy_start(struct seq_file *m, loff_t *pos)
void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct ima_namespace *ns = &init_ima_ns;
+ struct ima_namespace *ns = ima_ns_from_file(m->file);
struct ima_rule_entry *entry = v;
rcu_read_lock();