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-rw-r--r--security/integrity/ima/ima.h3
-rw-r--r--security/integrity/ima/ima_iint.c79
-rw-r--r--security/integrity/ima/ima_main.c184
3 files changed, 115 insertions, 151 deletions
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 165eb5397ea5..c41afe6639a0 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -97,7 +97,6 @@ static inline unsigned long ima_hash_key(u8 *digest)
/* iint cache flags */
#define IMA_MEASURED 1
-#define IMA_IINT_DUMP_STACK 512
/* integrity data associated with an inode */
struct ima_iint_cache {
@@ -128,8 +127,6 @@ void ima_template_show(struct seq_file *m, void *e,
*/
struct ima_iint_cache *ima_iint_insert(struct inode *inode);
struct ima_iint_cache *ima_iint_find_get(struct inode *inode);
-struct ima_iint_cache *ima_iint_find_insert_get(struct inode *inode);
-void ima_iint_delete(struct inode *inode);
void iint_free(struct kref *kref);
void iint_rcu_free(struct rcu_head *rcu);
diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c
index a4e2b1dac943..fa592ff1ac1c 100644
--- a/security/integrity/ima/ima_iint.c
+++ b/security/integrity/ima/ima_iint.c
@@ -19,8 +19,6 @@
#include <linux/radix-tree.h>
#include "ima.h"
-#define ima_iint_delete ima_inode_free
-
RADIX_TREE(ima_iint_store, GFP_ATOMIC);
DEFINE_SPINLOCK(ima_iint_lock);
@@ -45,22 +43,21 @@ out:
return iint;
}
-/* Allocate memory for the iint associated with the inode
- * from the iint_cache slab, initialize the iint, and
- * insert it into the radix tree.
- *
- * On success return a pointer to the iint; on failure return NULL.
+/**
+ * ima_inode_alloc - allocate an iint associated with an inode
+ * @inode: pointer to the inode
*/
-struct ima_iint_cache *ima_iint_insert(struct inode *inode)
+int ima_inode_alloc(struct inode *inode)
{
struct ima_iint_cache *iint = NULL;
int rc = 0;
if (!ima_initialized)
- return iint;
+ return 0;
+
iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
if (!iint)
- return iint;
+ return -ENOMEM;
rc = radix_tree_preload(GFP_NOFS);
if (rc < 0)
@@ -70,65 +67,13 @@ struct ima_iint_cache *ima_iint_insert(struct inode *inode)
rc = radix_tree_insert(&ima_iint_store, (unsigned long)inode, iint);
spin_unlock(&ima_iint_lock);
out:
- if (rc < 0) {
+ if (rc < 0)
kmem_cache_free(iint_cache, iint);
- if (rc == -EEXIST) {
- spin_lock(&ima_iint_lock);
- iint = radix_tree_lookup(&ima_iint_store,
- (unsigned long)inode);
- spin_unlock(&ima_iint_lock);
- } else
- iint = NULL;
- }
- radix_tree_preload_end();
- return iint;
-}
-
-/**
- * ima_inode_alloc - allocate an iint associated with an inode
- * @inode: pointer to the inode
- *
- * Return 0 on success, 1 on failure.
- */
-int ima_inode_alloc(struct inode *inode)
-{
- struct ima_iint_cache *iint;
-
- if (!ima_initialized)
- return 0;
-
- iint = ima_iint_insert(inode);
- if (!iint)
- return 1;
- return 0;
-}
-
-/* ima_iint_find_insert_get - get the iint associated with an inode
- *
- * Most insertions are done at inode_alloc, except those allocated
- * before late_initcall. When the iint does not exist, allocate it,
- * initialize and insert it, and increment the iint refcount.
- *
- * (Can't initialize at security_initcall before any inodes are
- * allocated, got to wait at least until proc_init.)
- *
- * Return the iint.
- */
-struct ima_iint_cache *ima_iint_find_insert_get(struct inode *inode)
-{
- struct ima_iint_cache *iint = NULL;
- iint = ima_iint_find_get(inode);
- if (iint)
- return iint;
-
- iint = ima_iint_insert(inode);
- if (iint)
- kref_get(&iint->refcount);
+ radix_tree_preload_end();
- return iint;
+ return rc;
}
-EXPORT_SYMBOL_GPL(ima_iint_find_insert_get);
/* iint_free - called when the iint refcount goes to zero */
void iint_free(struct kref *kref)
@@ -164,12 +109,12 @@ void iint_rcu_free(struct rcu_head *rcu_head)
}
/**
- * ima_iint_delete - called on integrity_inode_free
+ * ima_inode_free - called on security_inode_free
* @inode: pointer to the inode
*
* Free the integrity information(iint) associated with an inode.
*/
-void ima_iint_delete(struct inode *inode)
+void ima_inode_free(struct inode *inode)
{
struct ima_iint_cache *iint;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index b85e61bcf246..a89f44d5e030 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -13,8 +13,8 @@
* License.
*
* File: ima_main.c
- * implements the IMA hooks: ima_bprm_check, ima_file_mmap,
- * and ima_path_check.
+ * implements the IMA hooks: ima_bprm_check, ima_file_mmap,
+ * and ima_path_check.
*/
#include <linux/module.h>
#include <linux/file.h>
@@ -35,6 +35,100 @@ static int __init hash_setup(char *str)
}
__setup("ima_hash=", hash_setup);
+struct ima_imbalance {
+ struct hlist_node node;
+ unsigned long fsmagic;
+};
+
+/*
+ * ima_limit_imbalance - emit one imbalance message per filesystem type
+ *
+ * Maintain list of filesystem types that do not measure files properly.
+ * Return false if unknown, true if known.
+ */
+static bool ima_limit_imbalance(struct file *file)
+{
+ static DEFINE_SPINLOCK(ima_imbalance_lock);
+ static HLIST_HEAD(ima_imbalance_list);
+
+ struct super_block *sb = file->f_dentry->d_sb;
+ struct ima_imbalance *entry;
+ struct hlist_node *node;
+ bool found = false;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(entry, node, &ima_imbalance_list, node) {
+ if (entry->fsmagic == sb->s_magic) {
+ found = true;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ if (found)
+ goto out;
+
+ entry = kmalloc(sizeof(*entry), GFP_NOFS);
+ if (!entry)
+ goto out;
+ entry->fsmagic = sb->s_magic;
+ spin_lock(&ima_imbalance_lock);
+ /*
+ * we could have raced and something else might have added this fs
+ * to the list, but we don't really care
+ */
+ hlist_add_head_rcu(&entry->node, &ima_imbalance_list);
+ spin_unlock(&ima_imbalance_lock);
+ printk(KERN_INFO "IMA: unmeasured files on fsmagic: %lX\n",
+ entry->fsmagic);
+out:
+ return found;
+}
+
+/*
+ * Update the counts given an fmode_t
+ */
+static void ima_inc_counts(struct ima_iint_cache *iint, fmode_t mode)
+{
+ BUG_ON(!mutex_is_locked(&iint->mutex));
+
+ iint->opencount++;
+ if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
+ iint->readcount++;
+ if (mode & FMODE_WRITE)
+ iint->writecount++;
+}
+
+/*
+ * Decrement ima counts
+ */
+static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode,
+ struct file *file)
+{
+ mode_t mode = file->f_mode;
+ BUG_ON(!mutex_is_locked(&iint->mutex));
+
+ iint->opencount--;
+ if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
+ iint->readcount--;
+ if (mode & FMODE_WRITE) {
+ iint->writecount--;
+ if (iint->writecount == 0) {
+ if (iint->version != inode->i_version)
+ iint->flags &= ~IMA_MEASURED;
+ }
+ }
+
+ if (((iint->opencount < 0) ||
+ (iint->readcount < 0) ||
+ (iint->writecount < 0)) &&
+ !ima_limit_imbalance(file)) {
+ printk(KERN_INFO "%s: open/free imbalance (r:%ld w:%ld o:%ld)\n",
+ __FUNCTION__, iint->readcount, iint->writecount,
+ iint->opencount);
+ dump_stack();
+ }
+}
+
/**
* ima_file_free - called on __fput()
* @file: pointer to file structure being freed
@@ -54,29 +148,7 @@ void ima_file_free(struct file *file)
return;
mutex_lock(&iint->mutex);
- if (iint->opencount <= 0) {
- printk(KERN_INFO
- "%s: %s open/free imbalance (r:%ld w:%ld o:%ld f:%ld)\n",
- __FUNCTION__, file->f_dentry->d_name.name,
- iint->readcount, iint->writecount,
- iint->opencount, atomic_long_read(&file->f_count));
- if (!(iint->flags & IMA_IINT_DUMP_STACK)) {
- dump_stack();
- iint->flags |= IMA_IINT_DUMP_STACK;
- }
- }
- iint->opencount--;
-
- if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
- iint->readcount--;
-
- if (file->f_mode & FMODE_WRITE) {
- iint->writecount--;
- if (iint->writecount == 0) {
- if (iint->version != inode->i_version)
- iint->flags &= ~IMA_MEASURED;
- }
- }
+ ima_dec_counts(iint, inode, file);
mutex_unlock(&iint->mutex);
kref_put(&iint->refcount, iint_free);
}
@@ -116,8 +188,7 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file,
{
int rc = 0;
- iint->opencount++;
- iint->readcount++;
+ ima_inc_counts(iint, file->f_mode);
rc = ima_collect_measurement(iint, file);
if (!rc)
@@ -125,15 +196,6 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file,
return rc;
}
-static void ima_update_counts(struct ima_iint_cache *iint, int mask)
-{
- iint->opencount++;
- if ((mask & MAY_WRITE) || (mask == 0))
- iint->writecount++;
- else if (mask & (MAY_READ | MAY_EXEC))
- iint->readcount++;
-}
-
/**
* ima_path_check - based on policy, collect/store measurement.
* @path: contains a pointer to the path to be measured
@@ -152,7 +214,7 @@ static void ima_update_counts(struct ima_iint_cache *iint, int mask)
* Always return 0 and audit dentry_open failures.
* (Return code will be based upon measurement appraisal.)
*/
-int ima_path_check(struct path *path, int mask, int update_counts)
+int ima_path_check(struct path *path, int mask)
{
struct inode *inode = path->dentry->d_inode;
struct ima_iint_cache *iint;
@@ -161,13 +223,11 @@ int ima_path_check(struct path *path, int mask, int update_counts)
if (!ima_initialized || !S_ISREG(inode->i_mode))
return 0;
- iint = ima_iint_find_insert_get(inode);
+ iint = ima_iint_find_get(inode);
if (!iint)
return 0;
mutex_lock(&iint->mutex);
- if (update_counts)
- ima_update_counts(iint, mask);
rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK);
if (rc < 0)
@@ -219,7 +279,7 @@ static int process_measurement(struct file *file, const unsigned char *filename,
if (!ima_initialized || !S_ISREG(inode->i_mode))
return 0;
- iint = ima_iint_find_insert_get(inode);
+ iint = ima_iint_find_get(inode);
if (!iint)
return -ENOMEM;
@@ -238,39 +298,6 @@ out:
}
/*
- * ima_counts_put - decrement file counts
- *
- * File counts are incremented in ima_path_check. On file open
- * error, such as ETXTBSY, decrement the counts to prevent
- * unnecessary imbalance messages.
- */
-void ima_counts_put(struct path *path, int mask)
-{
- struct inode *inode = path->dentry->d_inode;
- struct ima_iint_cache *iint;
-
- /* The inode may already have been freed, freeing the iint
- * with it. Verify the inode is not NULL before dereferencing
- * it.
- */
- if (!ima_initialized || !inode || !S_ISREG(inode->i_mode))
- return;
- iint = ima_iint_find_insert_get(inode);
- if (!iint)
- return;
-
- mutex_lock(&iint->mutex);
- iint->opencount--;
- if ((mask & MAY_WRITE) || (mask == 0))
- iint->writecount--;
- else if (mask & (MAY_READ | MAY_EXEC))
- iint->readcount--;
- mutex_unlock(&iint->mutex);
-
- kref_put(&iint->refcount, iint_free);
-}
-
-/*
* ima_counts_get - increment file counts
*
* - for IPC shm and shmat file.
@@ -286,16 +313,11 @@ void ima_counts_get(struct file *file)
if (!ima_initialized || !S_ISREG(inode->i_mode))
return;
- iint = ima_iint_find_insert_get(inode);
+ iint = ima_iint_find_get(inode);
if (!iint)
return;
mutex_lock(&iint->mutex);
- iint->opencount++;
- if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
- iint->readcount++;
-
- if (file->f_mode & FMODE_WRITE)
- iint->writecount++;
+ ima_inc_counts(iint, file->f_mode);
mutex_unlock(&iint->mutex);
kref_put(&iint->refcount, iint_free);