The patch titled
Subject: mempool: do not use ksize() for poisoning
has been added to the -mm mm-unstable branch. Its filename is
mempool-do-not-use-ksize-for-poisoning.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mempool-do-not-use-ksize-for-poisoning.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: mempool: do not use ksize() for poisoning
Date: Fri, 28 Oct 2022 08:53:01 -0700
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.
Link: https://lkml.kernel.org/r/20221028154823.you.615-kees@xxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Suggested-by: Vlastimil Babka <vbabka@xxxxxxx>
Link: https://lore.kernel.org/lkml/f4fc52c4-7c18-1d76-0c7a-4058ea2486b9@xxxxxxx/
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/mm/mempool.c~mempool-do-not-use-ksize-for-poisoning
+++ a/mm/mempool.c
@@ -58,7 +58,7 @@ static void check_element(mempool_t *poo
{
/* 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 *po
{
/* 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
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);
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
mempool-do-not-use-ksize-for-poisoning.patch
