diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slab.c | 32 | ||||
| -rw-r--r-- | mm/slob.c | 5 | ||||
| -rw-r--r-- | mm/slub.c | 40 | ||||
| -rw-r--r-- | mm/util.c | 21 |
4 files changed, 1 insertions, 97 deletions
@@ -2781,7 +2781,7 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, /* * Map pages beginning at addr to the given cache and slab. This is required * for the slab allocator to be able to lookup the cache and slab of a - * virtual address for kfree, ksize, kmem_ptr_validate, and slab debugging. + * virtual address for kfree, ksize, and slab debugging. */ static void slab_map_pages(struct kmem_cache *cache, struct slab *slab, void *addr) @@ -3660,36 +3660,6 @@ void *kmem_cache_alloc_notrace(struct kmem_cache *cachep, gfp_t flags) EXPORT_SYMBOL(kmem_cache_alloc_notrace); #endif -/** - * kmem_ptr_validate - check if an untrusted pointer might be a slab entry. - * @cachep: the cache we're checking against - * @ptr: pointer to validate - * - * This verifies that the untrusted pointer looks sane; - * it is _not_ a guarantee that the pointer is actually - * part of the slab cache in question, but it at least - * validates that the pointer can be dereferenced and - * looks half-way sane. - * - * Currently only used for dentry validation. - */ -int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr) -{ - unsigned long size = cachep->buffer_size; - struct page *page; - - if (unlikely(!kern_ptr_validate(ptr, size))) - goto out; - page = virt_to_page(ptr); - if (unlikely(!PageSlab(page))) - goto out; - if (unlikely(page_get_cache(page) != cachep)) - goto out; - return 1; -out: - return 0; -} - #ifdef CONFIG_NUMA void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) { @@ -678,11 +678,6 @@ int kmem_cache_shrink(struct kmem_cache *d) } EXPORT_SYMBOL(kmem_cache_shrink); -int kmem_ptr_validate(struct kmem_cache *a, const void *b) -{ - return 0; -} - static unsigned int slob_ready __read_mostly; int slab_is_available(void) @@ -1917,17 +1917,6 @@ void kmem_cache_free(struct kmem_cache *s, void *x) } EXPORT_SYMBOL(kmem_cache_free); -/* Figure out on which slab page the object resides */ -static struct page *get_object_page(const void *x) -{ - struct page *page = virt_to_head_page(x); - - if (!PageSlab(page)) - return NULL; - - return page; -} - /* * Object placement in a slab is made very easy because we always start at * offset 0. If we tune the size of the object to the alignment then we can @@ -2386,35 +2375,6 @@ error: } /* - * Check if a given pointer is valid - */ -int kmem_ptr_validate(struct kmem_cache *s, const void *object) -{ - struct page *page; - - if (!kern_ptr_validate(object, s->size)) - return 0; - - page = get_object_page(object); - - if (!page || s != page->slab) - /* No slab or wrong slab */ - return 0; - - if (!check_valid_pointer(s, page, object)) - return 0; - - /* - * We could also check if the object is on the slabs freelist. - * But this would be too expensive and it seems that the main - * purpose of kmem_ptr_valid() is to check if the object belongs - * to a certain slab. - */ - return 1; -} -EXPORT_SYMBOL(kmem_ptr_validate); - -/* * Determine the size of a slab object */ unsigned int kmem_cache_size(struct kmem_cache *s) @@ -186,27 +186,6 @@ void kzfree(const void *p) } EXPORT_SYMBOL(kzfree); -int kern_ptr_validate(const void *ptr, unsigned long size) -{ - unsigned long addr = (unsigned long)ptr; - unsigned long min_addr = PAGE_OFFSET; - unsigned long align_mask = sizeof(void *) - 1; - - if (unlikely(addr < min_addr)) - goto out; - if (unlikely(addr > (unsigned long)high_memory - size)) - goto out; - if (unlikely(addr & align_mask)) - goto out; - if (unlikely(!kern_addr_valid(addr))) - goto out; - if (unlikely(!kern_addr_valid(addr + size - 1))) - goto out; - return 1; -out: - return 0; -} - /* * strndup_user - duplicate an existing string from user space * @s: The string to duplicate |
