The patch titled Subject: kasan: simplify assign_tag and set_tag calls has been added to the -mm tree. Its filename is kasan-simplify-assign_tag-and-set_tag-calls.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/kasan-simplify-assign_tag-and-set_tag-calls.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/kasan-simplify-assign_tag-and-set_tag-calls.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: kasan: simplify assign_tag and set_tag calls set_tag() already ignores the tag for the generic mode, so just call it as is. Add a check for the generic mode to assign_tag(), and simplify its call in ____kasan_kmalloc(). Link: https://lkml.kernel.org/r/eae2f21f9e412b508783f72c687cb0b76c151440.1605046662.git.andreyknvl@xxxxxxxxxx Link: https://linux-review.googlesource.com/id/I18905ca78fb4a3d60e1a34a4ca00247272480438 Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx> Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/kasan/common.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/mm/kasan/common.c~kasan-simplify-assign_tag-and-set_tag-calls +++ a/mm/kasan/common.c @@ -239,6 +239,9 @@ void __kasan_poison_object_data(struct k static u8 assign_tag(struct kmem_cache *cache, const void *object, bool init, bool keep_tag) { + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + return 0xff; + /* * 1. When an object is kmalloc()'ed, two hooks are called: * kasan_slab_alloc() and kasan_kmalloc(). We assign the @@ -281,8 +284,8 @@ void * __must_check __kasan_init_slab_ob __memset(alloc_meta, 0, sizeof(*alloc_meta)); } - if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) || IS_ENABLED(CONFIG_KASAN_HW_TAGS)) - object = set_tag(object, assign_tag(cache, object, true, false)); + /* Tag is ignored in set_tag() without CONFIG_KASAN_SW/HW_TAGS */ + object = set_tag(object, assign_tag(cache, object, true, false)); return (void *)object; } @@ -369,9 +372,7 @@ static void *____kasan_kmalloc(struct km KASAN_GRANULE_SIZE); redzone_end = round_up((unsigned long)object + cache->object_size, KASAN_GRANULE_SIZE); - - if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) || IS_ENABLED(CONFIG_KASAN_HW_TAGS)) - tag = assign_tag(cache, object, false, keep_tag); + tag = assign_tag(cache, object, false, keep_tag); /* Tag is ignored in set_tag without CONFIG_KASAN_SW/HW_TAGS */ kasan_unpoison_memory(set_tag(object, tag), size); _ Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are kasan-drop-unnecessary-gpl-text-from-comment-headers.patch kasan-kasan_vmalloc-depends-on-kasan_generic.patch kasan-group-vmalloc-code.patch s390-kasan-include-asm-pageh-from-asm-kasanh.patch kasan-shadow-declarations-only-for-software-modes.patch kasan-rename-unpoison_shadow-to-unpoison_memory.patch kasan-rename-kasan_shadow_-to-kasan_granule_.patch kasan-only-build-initc-for-software-modes.patch kasan-split-out-shadowc-from-commonc.patch kasan-define-kasan_granule_page.patch kasan-rename-report-and-tags-files.patch kasan-dont-duplicate-config-dependencies.patch kasan-hide-invalid-free-check-implementation.patch kasan-decode-stack-frame-only-with-kasan_stack_enable.patch kasan-arm64-only-init-shadow-for-software-modes.patch kasan-arm64-only-use-kasan_depth-for-software-modes.patch kasan-arm64-move-initialization-message.patch kasan-arm64-rename-kasan_init_tags-and-mark-as-__init.patch kasan-rename-addr_has_shadow-to-addr_has_metadata.patch kasan-rename-print_shadow_for_address-to-print_memory_metadata.patch kasan-kasan_non_canonical_hook-only-for-software-modes.patch kasan-rename-shadow-layout-macros-to-meta.patch kasan-separate-metadata_fetch_row-for-each-mode.patch kasan-arm64-dont-allow-sw_tags-with-arm64_mte.patch kasan-introduce-config_kasan_hw_tags.patch arm64-kasan-align-allocations-for-hw_tags.patch arm64-kasan-add-arch-layer-for-memory-tagging-helpers.patch kasan-define-kasan_granule_size-for-hw_tags.patch kasan-x86-s390-update-undef-config_kasan.patch kasan-arm64-expand-config_kasan-checks.patch kasan-arm64-implement-hw_tags-runtime.patch kasan-arm64-print-report-from-tag-fault-handler.patch kasan-mm-reset-tags-when-accessing-metadata.patch kasan-arm64-enable-config_kasan_hw_tags.patch kasan-add-documentation-for-hardware-tag-based-mode.patch kasan-simplify-quarantine_put-call-site.patch kasan-rename-get_alloc-free_info.patch kasan-introduce-set_alloc_info.patch kasan-arm64-unpoison-stack-only-with-config_kasan_stack.patch kasan-allow-vmap_stack-for-hw_tags-mode.patch kasan-remove-__kasan_unpoison_stack.patch kasan-inline-kasan_reset_tag-for-tag-based-modes.patch kasan-inline-random_tag-for-hw_tags.patch kasan-inline-kasan_poison_memory-and-check_invalid_free.patch kasan-inline-and-rename-kasan_unpoison_memory.patch kasan-add-and-integrate-kasan-boot-parameters.patch kasan-mm-check-kasan_enabled-in-annotations.patch kasan-simplify-kasan_poison_kfree.patch kasan-mm-rename-kasan_poison_kfree.patch kasan-dont-round_up-too-much.patch kasan-simplify-assign_tag-and-set_tag-calls.patch kasan-clarify-comment-in-__kasan_kfree_large.patch kasan-clean-up-metadata-allocation-and-usage.patch kasan-mm-allow-cache-merging-with-no-metadata.patch kasan-update-documentation.patch