From 330d8df81f3673d6fb74550bbc9bb159d81b35f7 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Tue, 22 Oct 2024 18:07:06 +0200 Subject: [PATCH] kasan: remove vmalloc_percpu test Commit 1a2473f0cbc0 ("kasan: improve vmalloc tests") added the vmalloc_percpu KASAN test with the assumption that __alloc_percpu always uses vmalloc internally, which is tagged by KASAN. However, __alloc_percpu might allocate memory from the first per-CPU chunk, which is not allocated via vmalloc(). As a result, the test might fail. Remove the test until proper KASAN annotation for the per-CPU allocated are added; tracked in https://bugzilla.kernel.org/show_bug.cgi?id=215019. Link: https://lkml.kernel.org/r/20241022160706.38943-1-andrey.konovalov@linux.dev Fixes: 1a2473f0cbc0 ("kasan: improve vmalloc tests") Signed-off-by: Andrey Konovalov Reported-by: Samuel Holland Link: https://lore.kernel.org/all/4a245fff-cc46-44d1-a5f9-fd2f1c3764ae@sifive.com/ Reported-by: Sabyrzhan Tasbolatov Link: https://lore.kernel.org/all/CACzwLxiWzNqPBp4C1VkaXZ2wDwvY3yZeetCi1TLGFipKW77drA@mail.gmail.com/ Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Marco Elver Cc: Sabyrzhan Tasbolatov Cc: Signed-off-by: Andrew Morton --- mm/kasan/kasan_test_c.c | 27 --------------------------- 1 file changed, 27 deletions(-) diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c index a181e4780d9d..d8fb281e439d 100644 --- a/mm/kasan/kasan_test_c.c +++ b/mm/kasan/kasan_test_c.c @@ -1810,32 +1810,6 @@ static void vm_map_ram_tags(struct kunit *test) free_pages((unsigned long)p_ptr, 1); } -static void vmalloc_percpu(struct kunit *test) -{ - char __percpu *ptr; - int cpu; - - /* - * This test is specifically crafted for the software tag-based mode, - * the only tag-based mode that poisons percpu mappings. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); - - ptr = __alloc_percpu(PAGE_SIZE, PAGE_SIZE); - - for_each_possible_cpu(cpu) { - char *c_ptr = per_cpu_ptr(ptr, cpu); - - KUNIT_EXPECT_GE(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_KERNEL); - - /* Make sure that in-bounds accesses don't crash the kernel. */ - *c_ptr = 0; - } - - free_percpu(ptr); -} - /* * Check that the assigned pointer tag falls within the [KASAN_TAG_MIN, * KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based @@ -2023,7 +1997,6 @@ static struct kunit_case kasan_kunit_test_cases[] = { KUNIT_CASE(vmalloc_oob), KUNIT_CASE(vmap_tags), KUNIT_CASE(vm_map_ram_tags), - KUNIT_CASE(vmalloc_percpu), KUNIT_CASE(match_all_not_assigned), KUNIT_CASE(match_all_ptr_tag), KUNIT_CASE(match_all_mem_tag),