From: Daniel Axtens <dja@xxxxxxxxxx> Subject: kasan: add test for vmalloc Test kasan vmalloc support by adding a new test to the module. Link: http://lkml.kernel.org/r/20191031093909.9228-3-dja@xxxxxxxxxx Signed-off-by: Daniel Axtens <dja@xxxxxxxxxx> Reviewed-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/test_kasan.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) --- a/lib/test_kasan.c~kasan-add-test-for-vmalloc +++ a/lib/test_kasan.c @@ -19,6 +19,7 @@ #include <linux/string.h> #include <linux/uaccess.h> #include <linux/io.h> +#include <linux/vmalloc.h> #include <asm/page.h> @@ -748,6 +749,30 @@ static noinline void __init kmalloc_doub kzfree(ptr); } +#ifdef CONFIG_KASAN_VMALLOC +static noinline void __init vmalloc_oob(void) +{ + void *area; + + pr_info("vmalloc out-of-bounds\n"); + + /* + * We have to be careful not to hit the guard page. + * The MMU will catch that and crash us. + */ + area = vmalloc(3000); + if (!area) { + pr_err("Allocation failed\n"); + return; + } + + ((volatile char *)area)[3100]; + vfree(area); +} +#else +static void __init vmalloc_oob(void) {} +#endif + static int __init kmalloc_tests_init(void) { /* @@ -793,6 +818,7 @@ static int __init kmalloc_tests_init(voi kasan_strings(); kasan_bitops(); kmalloc_double_kzfree(); + vmalloc_oob(); kasan_restore_multi_shot(multishot); _
