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-rw-r--r--security/integrity/ima/ima_main.c94
1 files changed, 64 insertions, 30 deletions
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 2a77b14fee27..5e3229c797fc 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -141,33 +141,62 @@ out:
/*
* Decrement ima counts
*/
-static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode,
- struct file *file)
+static void ima_dec_counts(struct inode *inode, struct file *file)
{
mode_t mode = file->f_mode;
- bool dump = false;
- BUG_ON(!mutex_is_locked(&iint->mutex));
assert_spin_locked(&inode->i_lock);
if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
- if (unlikely(inode->i_readcount == 0))
- dump = true;
+ if (unlikely(inode->i_readcount == 0)) {
+ if (!ima_limit_imbalance(file)) {
+ printk(KERN_INFO "%s: open/free imbalance (r:%u)\n",
+ __func__, inode->i_readcount);
+ dump_stack();
+ }
+ return;
+ }
inode->i_readcount--;
}
- if (mode & FMODE_WRITE) {
- if (atomic_read(&inode->i_writecount) <= 0)
- dump = true;
- if (atomic_read(&inode->i_writecount) == 1 &&
- iint->version != inode->i_version)
- iint->flags &= ~IMA_MEASURED;
- }
+}
- if (dump && !ima_limit_imbalance(file)) {
- printk(KERN_INFO "%s: open/free imbalance (r:%u)\n",
- __func__, inode->i_readcount);
- dump_stack();
- }
+static void ima_check_last_writer(struct ima_iint_cache *iint,
+ struct inode *inode,
+ struct file *file)
+{
+ mode_t mode = file->f_mode;
+
+ BUG_ON(!mutex_is_locked(&iint->mutex));
+ assert_spin_locked(&inode->i_lock);
+
+ if (mode & FMODE_WRITE &&
+ atomic_read(&inode->i_writecount) == 1 &&
+ iint->version != inode->i_version)
+ iint->flags &= ~IMA_MEASURED;
+}
+
+static void ima_file_free_iint(struct ima_iint_cache *iint, struct inode *inode,
+ struct file *file)
+{
+ mutex_lock(&iint->mutex);
+ spin_lock(&inode->i_lock);
+
+ ima_dec_counts(inode, file);
+ ima_check_last_writer(iint, inode, file);
+
+ spin_unlock(&inode->i_lock);
+ mutex_unlock(&iint->mutex);
+
+ kref_put(&iint->refcount, iint_free);
+}
+
+static void ima_file_free_noiint(struct inode *inode, struct file *file)
+{
+ spin_lock(&inode->i_lock);
+
+ ima_dec_counts(inode, file);
+
+ spin_unlock(&inode->i_lock);
}
/**
@@ -175,7 +204,7 @@ static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode,
* @file: pointer to file structure being freed
*
* Flag files that changed, based on i_version;
- * and decrement the iint readcount/writecount.
+ * and decrement the i_readcount.
*/
void ima_file_free(struct file *file)
{
@@ -185,17 +214,12 @@ void ima_file_free(struct file *file)
if (!iint_initialized || !S_ISREG(inode->i_mode))
return;
iint = ima_iint_find_get(inode);
- if (!iint)
- return;
- mutex_lock(&iint->mutex);
- spin_lock(&inode->i_lock);
-
- ima_dec_counts(iint, inode, file);
+ if (iint)
+ ima_file_free_iint(iint, inode, file);
+ else
+ ima_file_free_noiint(inode, file);
- spin_unlock(&inode->i_lock);
- mutex_unlock(&iint->mutex);
- kref_put(&iint->refcount, iint_free);
}
static int process_measurement(struct file *file, const unsigned char *filename,
@@ -207,11 +231,21 @@ static int process_measurement(struct file *file, const unsigned char *filename,
if (!ima_initialized || !S_ISREG(inode->i_mode))
return 0;
+
+ rc = ima_must_measure(NULL, inode, mask, function);
+ if (rc != 0)
+ return rc;
+retry:
iint = ima_iint_find_get(inode);
- if (!iint)
- return -ENOMEM;
+ if (!iint) {
+ rc = ima_inode_alloc(inode);
+ if (!rc || rc == -EEXIST)
+ goto retry;
+ return rc;
+ }
mutex_lock(&iint->mutex);
+
rc = ima_must_measure(iint, inode, mask, function);
if (rc != 0)
goto out;