From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754658AbbIQJic (ORCPT ); Thu, 17 Sep 2015 05:38:32 -0400 Received: from mail-lb0-f181.google.com ([209.85.217.181]:34584 "EHLO mail-lb0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754583AbbIQJiZ (ORCPT ); Thu, 17 Sep 2015 05:38:25 -0400 From: Andrey Ryabinin To: Will Deacon , Catalin Marinas , linux-arm-kernel@lists.infradead.org Cc: Andrey Ryabinin , Matt Fleming , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-efi@vger.kernel.org, fengguang.wu@intel.com, Linus Walleij , Alexander Potapenko , Dmitry Vyukov , Arnd Bergmann , linux-kernel@vger.kernel.org, David Keitel , linux-mm@kvack.org, Alexey Klimov , Yury , Andrey Konovalov Subject: [PATCH v6 3/6] x86, efi, kasan: #undef memset/memcpy/memmove per arch. Date: Thu, 17 Sep 2015 12:38:09 +0300 Message-Id: <1442482692-6416-4-git-send-email-ryabinin.a.a@gmail.com> X-Mailer: git-send-email 2.4.6 In-Reply-To: <1442482692-6416-1-git-send-email-ryabinin.a.a@gmail.com> References: <1442482692-6416-1-git-send-email-ryabinin.a.a@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In not-instrumented code KASAN replaces instrumented memset/memcpy/memmove with not-instrumented analogues __memset/__memcpy/__memove. However, on x86 the EFI stub is not linked with the kernel. It uses not-instrumented mem*() functions from arch/x86/boot/compressed/string.c So we don't replace them with __mem*() variants in EFI stub. On ARM64 the EFI stub is linked with the kernel, so we should replace mem*() functions with __mem*(), because the EFI stub runs before KASAN sets up early shadow. So let's move these #undef mem* into arch's asm/efi.h which is also included by the EFI stub. Also, this will fix the warning in 32-bit build reported by kbuild test robot : efi-stub-helper.c:599:2: warning: implicit declaration of function 'memcpy' Signed-off-by: Andrey Ryabinin --- arch/x86/include/asm/efi.h | 12 ++++++++++++ drivers/firmware/efi/libstub/efistub.h | 4 ---- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index 155162e..6db2742 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -86,6 +86,18 @@ extern u64 asmlinkage efi_call(void *fp, ...); extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size, u32 type, u64 attribute); +/* + * CONFIG_KASAN may redefine memset to __memset. + * __memset function is present only in kernel binary. + * Since the EFI stub linked into a separate binary it + * doesn't have __memset(). So we should use standard + * memset from arch/x86/boot/compressed/string.c + * The same applies to memcpy and memmove. + */ +#undef memcpy +#undef memset +#undef memmove + #endif /* CONFIG_X86_32 */ extern struct efi_scratch efi_scratch; diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index e334a01..6b6548f 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -5,10 +5,6 @@ /* error code which can't be mistaken for valid address */ #define EFI_ERROR (~0UL) -#undef memcpy -#undef memset -#undef memmove - void efi_char16_printk(efi_system_table_t *, efi_char16_t *); efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image, -- 2.4.6