slub: ksize() abuse checks

Add a WARN_ON for pages that don't have PageSlab nor PageCompound set to catch the worst abusers of ksize() in the kernel. Acked-by: Christoph Lameter <clameter@sgi.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
git-mirror · May 22, 2008 · 7699441 · 7699441
1 parent 239f49c
commit 7699441
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/mm/slub.c b/mm/slub.c
@@ -2726,9 +2726,10 @@ size_t ksize(const void *object)
 
 	page = virt_to_head_page(object);
 
-	if (unlikely(!PageSlab(page)))
+	if (unlikely(!PageSlab(page))) {
+		WARN_ON(!PageCompound(page));
 		return PAGE_SIZE << compound_order(page);
-
+	}
 	s = page->slab;
 
 #ifdef CONFIG_SLUB_DEBUG