From: Sabyrzhan Tasbolatov Date: Thu, 9 Oct 2025 15:54:03 +0000 (+0500) Subject: kasan: cleanup of kasan_enabled() checks X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a8cb648cab380a912ac7519117b73925c0c05191;p=users%2Fjedix%2Flinux-maple.git kasan: cleanup of kasan_enabled() checks Deduplication of kasan_enabled() checks which are already used by callers. * Altered functions: check_page_allocation Delete the check because callers have it already in __wrappers in include/linux/kasan.h: __kasan_kfree_large __kasan_mempool_poison_pages __kasan_mempool_poison_object kasan_populate_vmalloc, kasan_release_vmalloc Add __wrappers in include/linux/kasan.h. They are called externally in mm/vmalloc.c. __kasan_unpoison_vmalloc, __kasan_poison_vmalloc Delete checks because there're already kasan_enabled() checks in respective __wrappers in include/linux/kasan.h. release_free_meta -- Delete the check because the higher caller path has it already. See the stack trace: __kasan_slab_free -- has the check already __kasan_mempool_poison_object -- has the check already poison_slab_object kasan_save_free_info release_free_meta kasan_enabled() -- Delete here Link: https://lkml.kernel.org/r/20251009155403.1379150-3-snovitoll@gmail.com Signed-off-by: Sabyrzhan Tasbolatov Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Baoquan He Cc: Christophe Leroy Cc: Dmitriy Vyukov Cc: "Ritesh Harjani (IBM)" Cc: Vincenzo Frascino Signed-off-by: Andrew Morton --- diff --git a/include/linux/kasan.h b/include/linux/kasan.h index d12e1a5f5a9a..f335c1d7b61d 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -571,11 +571,27 @@ static inline void kasan_init_hw_tags(void) { } #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) void kasan_populate_early_vm_area_shadow(void *start, unsigned long size); -int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask); -void kasan_release_vmalloc(unsigned long start, unsigned long end, +int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask); +static inline int kasan_populate_vmalloc(unsigned long addr, + unsigned long size, gfp_t gfp_mask) +{ + if (kasan_enabled()) + return __kasan_populate_vmalloc(addr, size, gfp_mask); + return 0; +} +void __kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long free_region_start, unsigned long free_region_end, unsigned long flags); +static inline void kasan_release_vmalloc(unsigned long start, unsigned long end, + unsigned long free_region_start, + unsigned long free_region_end, + unsigned long flags) +{ + if (kasan_enabled()) + return __kasan_release_vmalloc(start, end, free_region_start, + free_region_end, flags); +} #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ diff --git a/mm/kasan/common.c b/mm/kasan/common.c index d4c14359feaf..22e5d67ff064 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -305,9 +305,6 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, bool init, static inline bool check_page_allocation(void *ptr, unsigned long ip) { - if (!kasan_enabled()) - return false; - if (ptr != page_address(virt_to_head_page(ptr))) { kasan_report_invalid_free(ptr, ip, KASAN_REPORT_INVALID_FREE); return true; diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c index 516b49accc4f..2b8e73f5f6a7 100644 --- a/mm/kasan/generic.c +++ b/mm/kasan/generic.c @@ -506,9 +506,6 @@ static void release_alloc_meta(struct kasan_alloc_meta *meta) static void release_free_meta(const void *object, struct kasan_free_meta *meta) { - if (!kasan_enabled()) - return; - /* Check if free meta is valid. */ if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREE_META) return; diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c index a30d84bfdd52..29a751a8a08d 100644 --- a/mm/kasan/shadow.c +++ b/mm/kasan/shadow.c @@ -354,7 +354,7 @@ static int ___alloc_pages_bulk(struct page **pages, int nr_pages, gfp_t gfp_mask return 0; } -static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_t gfp_mask) +static int __kasan_populate_vmalloc_do(unsigned long start, unsigned long end, gfp_t gfp_mask) { unsigned long nr_pages, nr_total = PFN_UP(end - start); struct vmalloc_populate_data data; @@ -395,14 +395,11 @@ static int __kasan_populate_vmalloc(unsigned long start, unsigned long end, gfp_ return ret; } -int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask) +int __kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mask) { unsigned long shadow_start, shadow_end; int ret; - if (!kasan_enabled()) - return 0; - if (!is_vmalloc_or_module_addr((void *)addr)) return 0; @@ -424,7 +421,7 @@ int kasan_populate_vmalloc(unsigned long addr, unsigned long size, gfp_t gfp_mas shadow_start = PAGE_ALIGN_DOWN(shadow_start); shadow_end = PAGE_ALIGN(shadow_end); - ret = __kasan_populate_vmalloc(shadow_start, shadow_end, gfp_mask); + ret = __kasan_populate_vmalloc_do(shadow_start, shadow_end, gfp_mask); if (ret) return ret; @@ -566,7 +563,7 @@ static int kasan_depopulate_vmalloc_pte(pte_t *ptep, unsigned long addr, * pages entirely covered by the free region, we will not run in to any * trouble - any simultaneous allocations will be for disjoint regions. */ -void kasan_release_vmalloc(unsigned long start, unsigned long end, +void __kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long free_region_start, unsigned long free_region_end, unsigned long flags) @@ -575,9 +572,6 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long region_start, region_end; unsigned long size; - if (!kasan_enabled()) - return; - region_start = ALIGN(start, KASAN_MEMORY_PER_SHADOW_PAGE); region_end = ALIGN_DOWN(end, KASAN_MEMORY_PER_SHADOW_PAGE); @@ -626,9 +620,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size, * with setting memory tags, so the KASAN_VMALLOC_INIT flag is ignored. */ - if (!kasan_enabled()) - return (void *)start; - if (!is_vmalloc_or_module_addr(start)) return (void *)start; @@ -651,9 +642,6 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size, */ void __kasan_poison_vmalloc(const void *start, unsigned long size) { - if (!kasan_enabled()) - return; - if (!is_vmalloc_or_module_addr(start)) return;