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-rw-r--r--security/tomoyo/realpath.c65
1 files changed, 20 insertions, 45 deletions
diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c
index 9105e5e29da..54226d5be49 100644
--- a/security/tomoyo/realpath.c
+++ b/security/tomoyo/realpath.c
@@ -212,57 +212,32 @@ static unsigned int tomoyo_allocated_memory_for_elements;
static unsigned int tomoyo_quota_for_elements;
/**
- * tomoyo_alloc_element - Allocate permanent memory for structures.
+ * tomoyo_memory_ok - Check memory quota.
*
- * @size: Size in bytes.
+ * @ptr: Pointer to allocated memory.
*
- * Returns pointer to allocated memory on success, NULL otherwise.
+ * Returns true on success, false otherwise.
*
- * Memory has to be zeroed.
- * The RAM is chunked, so NEVER try to kfree() the returned pointer.
+ * Caller holds tomoyo_policy_lock.
+ * Memory pointed by @ptr will be zeroed on success.
*/
-void *tomoyo_alloc_element(const unsigned int size)
+bool tomoyo_memory_ok(void *ptr)
{
- static char *buf;
- static DEFINE_MUTEX(lock);
- static unsigned int buf_used_len = PATH_MAX;
- char *ptr = NULL;
- /*Assumes sizeof(void *) >= sizeof(long) is true. */
- const unsigned int word_aligned_size
- = roundup(size, max(sizeof(void *), sizeof(long)));
- if (word_aligned_size > PATH_MAX)
- return NULL;
- mutex_lock(&lock);
- if (buf_used_len + word_aligned_size > PATH_MAX) {
- if (!tomoyo_quota_for_elements ||
- tomoyo_allocated_memory_for_elements
- + PATH_MAX <= tomoyo_quota_for_elements)
- ptr = kzalloc(PATH_MAX, GFP_KERNEL);
- if (!ptr) {
- printk(KERN_WARNING "ERROR: Out of memory "
- "for tomoyo_alloc_element().\n");
- if (!tomoyo_policy_loaded)
- panic("MAC Initialization failed.\n");
- } else {
- buf = ptr;
- tomoyo_allocated_memory_for_elements += PATH_MAX;
- buf_used_len = word_aligned_size;
- ptr = buf;
- }
- } else if (word_aligned_size) {
- int i;
- ptr = buf + buf_used_len;
- buf_used_len += word_aligned_size;
- for (i = 0; i < word_aligned_size; i++) {
- if (!ptr[i])
- continue;
- printk(KERN_ERR "WARNING: Reserved memory was tainted! "
- "The system might go wrong.\n");
- ptr[i] = '\0';
- }
+ int allocated_len = ptr ? ksize(ptr) : 0;
+ bool result = false;
+ if (!ptr || (tomoyo_quota_for_elements &&
+ tomoyo_allocated_memory_for_elements
+ + allocated_len > tomoyo_quota_for_elements)) {
+ printk(KERN_WARNING "ERROR: Out of memory "
+ "for tomoyo_alloc_element().\n");
+ if (!tomoyo_policy_loaded)
+ panic("MAC Initialization failed.\n");
+ } else {
+ result = true;
+ tomoyo_allocated_memory_for_elements += allocated_len;
+ memset(ptr, 0, allocated_len);
}
- mutex_unlock(&lock);
- return ptr;
+ return result;
}
/* Memory allocated for string data in bytes. */