shmem: fix tmpfs to handle the huge= option properly

[cascardo/linux.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index 850737b..9adae58 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3629,6 +3629,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
  */
 static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
 {
+       LIST_HEAD(discard);
        struct page *page, *h;
 
        BUG_ON(irqs_disabled());
@@ -3636,13 +3637,16 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
        list_for_each_entry_safe(page, h, &n->partial, lru) {
                if (!page->inuse) {
                        remove_partial(n, page);
-                       discard_slab(s, page);
+                       list_add(&page->lru, &discard);
                } else {
                        list_slab_objects(s, page,
                        "Objects remaining in %s on __kmem_cache_shutdown()");
                }
        }
        spin_unlock_irq(&n->list_lock);
+
+       list_for_each_entry_safe(page, h, &discard, lru)
+               discard_slab(s, page);
 }
 
 /*
@@ -3764,6 +3768,46 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
 EXPORT_SYMBOL(__kmalloc_node);
 #endif
 
+#ifdef CONFIG_HARDENED_USERCOPY
+/*
+ * Rejects objects that are incorrectly sized.
+ *
+ * Returns NULL if check passes, otherwise const char * to name of cache
+ * to indicate an error.
+ */
+const char *__check_heap_object(const void *ptr, unsigned long n,
+                               struct page *page)
+{
+       struct kmem_cache *s;
+       unsigned long offset;
+       size_t object_size;
+
+       /* Find object and usable object size. */
+       s = page->slab_cache;
+       object_size = slab_ksize(s);
+
+       /* Reject impossible pointers. */
+       if (ptr < page_address(page))
+               return s->name;
+
+       /* Find offset within object. */
+       offset = (ptr - page_address(page)) % s->size;
+
+       /* Adjust for redzone and reject if within the redzone. */
+       if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) {
+               if (offset < s->red_left_pad)
+                       return s->name;
+               offset -= s->red_left_pad;
+       }
+
+       /* Allow address range falling entirely within object size. */
+       if (offset <= object_size && n <= object_size - offset)
+               return NULL;
+
+       return s->name;
+}
+#endif /* CONFIG_HARDENED_USERCOPY */
+
 static size_t __ksize(const void *object)
 {
        struct page *page;