X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=mm%2Fkmemleak.c;h=cbae846a52821ecc3a2faf59683b44f34d8bdf56;hp=f3b2a00fe9c1fa3b0d4d5bb0a419d439f00b6062;hb=9f249188a2927b7809ed790e4b568ea82039d919;hpb=3b971a7ceb2e39e0cab95c079c738b2052b3e02f

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index f3b2a00fe9c1..cbae846a5282 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -192,6 +192,8 @@ static struct kmem_cache *scan_area_cache;
 
 /* set if tracing memory operations is enabled */
 static atomic_t kmemleak_enabled = ATOMIC_INIT(0);
+/* same as above but only for the kmemleak_free() callback */
+static int kmemleak_free_enabled;
 /* set in the late_initcall if there were no errors */
 static atomic_t kmemleak_initialized = ATOMIC_INIT(0);
 /* enables or disables early logging of the memory operations */
@@ -744,7 +746,9 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
 	}
 
 	spin_lock_irqsave(&object->lock, flags);
-	if (ptr + size > object->pointer + object->size) {
+	if (size == SIZE_MAX) {
+		size = object->pointer + object->size - ptr;
+	} else if (ptr + size > object->pointer + object->size) {
 		kmemleak_warn("Scan area larger than object 0x%08lx\n", ptr);
 		dump_object_info(object);
 		kmem_cache_free(scan_area_cache, area);
@@ -883,7 +887,7 @@ void __ref kmemleak_free(const void *ptr)
 {
 	pr_debug("%s(0x%p)\n", __func__, ptr);
 
-	if (atomic_read(&kmemleak_enabled) && ptr && !IS_ERR(ptr))
+	if (kmemleak_free_enabled && ptr && !IS_ERR(ptr))
 		delete_object_full((unsigned long)ptr);
 	else if (atomic_read(&kmemleak_early_log))
 		log_early(KMEMLEAK_FREE, ptr, 0, 0);
@@ -1612,6 +1616,13 @@ static void kmemleak_do_cleanup(struct work_struct *work)
 	mutex_lock(&scan_mutex);
 	stop_scan_thread();
 
+	/*
+	 * Once the scan thread has stopped, it is safe to no longer track
+	 * object freeing. Ordering of the scan thread stopping and the memory
+	 * accesses below is guaranteed by the kthread_stop() function.
+	 */
+	kmemleak_free_enabled = 0;
+
 	rcu_read_lock();
 	list_for_each_entry_rcu(object, &object_list, object_list)
 		delete_object_full(object->pointer);
@@ -1638,6 +1649,8 @@ static void kmemleak_disable(void)
 	/* check whether it is too early for a kernel thread */
 	if (atomic_read(&kmemleak_initialized))
 		schedule_work(&cleanup_work);
+	else
+		kmemleak_free_enabled = 0;
 
 	pr_info("Kernel memory leak detector disabled\n");
 }
@@ -1686,6 +1699,7 @@ void __init kmemleak_init(void)
 	if (!atomic_read(&kmemleak_error)) {
 		atomic_set(&kmemleak_enabled, 1);
 		atomic_set(&kmemleak_early_log, 0);
+		kmemleak_free_enabled = 1;
 	}
 	local_irq_restore(flags);