Nothing appears to be using ksize() within the kmalloc-backed mempools except the mempool poisoning logic. Use the actual pool size instead of the ksize() to avoid needing any special handling of the memory as needed by KASAN, UBSAN_BOUNDS, nor FORTIFY_SOURCE. Suggested-by: Vlastimil Babka <vbabka@xxxxxxx> Link: https://lore.kernel.org/lkml/f4fc52c4-7c18-1d76-0c7a-4058ea2486b9@xxxxxxx/ Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- This replaces mempool-use-kmalloc_size_roundup-to-match-ksize-usage.patch v4: add review/ack tags, explicitly call out subject change v3: https://lore.kernel.org/lkml/20221025233421.you.825-kees@xxxxxxxxxx/ v2: https://lore.kernel.org/lkml/20221018090323.never.897-kees@xxxxxxxxxx/ v1: https://lore.kernel.org/lkml/20220923202822.2667581-14-keescook@xxxxxxxxxxxx/ --- mm/mempool.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/mm/mempool.c b/mm/mempool.c index 96488b13a1ef..54204065037d 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -58,7 +58,7 @@ static void check_element(mempool_t *pool, void *element) { /* Mempools backed by slab allocator */ if (pool->free == mempool_free_slab || pool->free == mempool_kfree) { - __check_element(pool, element, ksize(element)); + __check_element(pool, element, (size_t)pool->pool_data); } else if (pool->free == mempool_free_pages) { /* Mempools backed by page allocator */ int order = (int)(long)pool->pool_data; @@ -81,7 +81,7 @@ static void poison_element(mempool_t *pool, void *element) { /* Mempools backed by slab allocator */ if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) { - __poison_element(element, ksize(element)); + __poison_element(element, (size_t)pool->pool_data); } else if (pool->alloc == mempool_alloc_pages) { /* Mempools backed by page allocator */ int order = (int)(long)pool->pool_data; @@ -112,7 +112,7 @@ static __always_inline void kasan_poison_element(mempool_t *pool, void *element) static void kasan_unpoison_element(mempool_t *pool, void *element) { if (pool->alloc == mempool_alloc_slab || pool->alloc == mempool_kmalloc) - kasan_unpoison_range(element, __ksize(element)); + kasan_unpoison_range(element, (size_t)pool->pool_data); else if (pool->alloc == mempool_alloc_pages) kasan_unpoison_pages(element, (unsigned long)pool->pool_data, false); -- 2.34.1