From 58ff537109ac863d4ec83baf8413b17dcc10101c Mon Sep 17 00:00:00 2001 From: Samuel Holland <samuel.holland@sifive.com> Date: Wed, 31 Jul 2024 20:36:59 -0700 Subject: [PATCH] riscv: Omit optimized string routines when using KASAN The optimized string routines are implemented in assembly, so they are not instrumented for use with KASAN. Fall back to the C version of the routines in order to improve KASAN coverage. This fixes the kasan_strings() unit test. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240801033725.28816-2-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> --- arch/riscv/include/asm/string.h | 2 ++ arch/riscv/kernel/riscv_ksyms.c | 3 --- arch/riscv/lib/Makefile | 2 ++ arch/riscv/lib/strcmp.S | 1 + arch/riscv/lib/strlen.S | 1 + arch/riscv/lib/strncmp.S | 1 + arch/riscv/purgatory/Makefile | 2 ++ 7 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h index a96b1fea24fe..5ba77f60bf0b 100644 --- a/arch/riscv/include/asm/string.h +++ b/arch/riscv/include/asm/string.h @@ -19,6 +19,7 @@ extern asmlinkage void *__memcpy(void *, const void *, size_t); extern asmlinkage void *memmove(void *, const void *, size_t); extern asmlinkage void *__memmove(void *, const void *, size_t); +#if !(defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) #define __HAVE_ARCH_STRCMP extern asmlinkage int strcmp(const char *cs, const char *ct); @@ -27,6 +28,7 @@ extern asmlinkage __kernel_size_t strlen(const char *); #define __HAVE_ARCH_STRNCMP extern asmlinkage int strncmp(const char *cs, const char *ct, size_t count); +#endif /* For those files which don't want to check by kasan. */ #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) diff --git a/arch/riscv/kernel/riscv_ksyms.c b/arch/riscv/kernel/riscv_ksyms.c index a72879b4249a..5ab1c7e1a6ed 100644 --- a/arch/riscv/kernel/riscv_ksyms.c +++ b/arch/riscv/kernel/riscv_ksyms.c @@ -12,9 +12,6 @@ EXPORT_SYMBOL(memset); EXPORT_SYMBOL(memcpy); EXPORT_SYMBOL(memmove); -EXPORT_SYMBOL(strcmp); -EXPORT_SYMBOL(strlen); -EXPORT_SYMBOL(strncmp); EXPORT_SYMBOL(__memset); EXPORT_SYMBOL(__memcpy); EXPORT_SYMBOL(__memmove); diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index 2b369f51b0a5..8eec6b69a875 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -3,9 +3,11 @@ lib-y += delay.o lib-y += memcpy.o lib-y += memset.o lib-y += memmove.o +ifeq ($(CONFIG_KASAN_GENERIC)$(CONFIG_KASAN_SW_TAGS),) lib-y += strcmp.o lib-y += strlen.o lib-y += strncmp.o +endif lib-y += csum.o ifeq ($(CONFIG_MMU), y) lib-$(CONFIG_RISCV_ISA_V) += uaccess_vector.o diff --git a/arch/riscv/lib/strcmp.S b/arch/riscv/lib/strcmp.S index 687b2bea5c43..542301a67a2f 100644 --- a/arch/riscv/lib/strcmp.S +++ b/arch/riscv/lib/strcmp.S @@ -120,3 +120,4 @@ strcmp_zbb: .option pop #endif SYM_FUNC_END(strcmp) +EXPORT_SYMBOL(strcmp) diff --git a/arch/riscv/lib/strlen.S b/arch/riscv/lib/strlen.S index 8ae3064e45ff..962983b73251 100644 --- a/arch/riscv/lib/strlen.S +++ b/arch/riscv/lib/strlen.S @@ -131,3 +131,4 @@ strlen_zbb: #endif SYM_FUNC_END(strlen) SYM_FUNC_ALIAS(__pi_strlen, strlen) +EXPORT_SYMBOL(strlen) diff --git a/arch/riscv/lib/strncmp.S b/arch/riscv/lib/strncmp.S index aba5b3148621..0f359ea2f55b 100644 --- a/arch/riscv/lib/strncmp.S +++ b/arch/riscv/lib/strncmp.S @@ -136,3 +136,4 @@ strncmp_zbb: .option pop #endif SYM_FUNC_END(strncmp) +EXPORT_SYMBOL(strncmp) diff --git a/arch/riscv/purgatory/Makefile b/arch/riscv/purgatory/Makefile index f11945ee2490..fb9c917c9b45 100644 --- a/arch/riscv/purgatory/Makefile +++ b/arch/riscv/purgatory/Makefile @@ -1,7 +1,9 @@ # SPDX-License-Identifier: GPL-2.0 purgatory-y := purgatory.o sha256.o entry.o string.o ctype.o memcpy.o memset.o +ifeq ($(CONFIG_KASAN_GENERIC)$(CONFIG_KASAN_SW_TAGS),) purgatory-y += strcmp.o strlen.o strncmp.o +endif targets += $(purgatory-y) PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))