Unverified Commit 58ff5371 authored by Samuel Holland's avatar Samuel Holland Committed by Palmer Dabbelt
Browse files

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: default avatarSamuel Holland <samuel.holland@sifive.com>
Reviewed-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240801033725.28816-2-samuel.holland@sifive.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 8400291e

arch/riscv/include/asm/string.h

+2 −0
Original line number Diff line number Diff line
@@ -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__)

arch/riscv/kernel/riscv_ksyms.c

+0 −3
Original line number Diff line number Diff line
@@ -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);

arch/riscv/lib/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -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

arch/riscv/lib/strcmp.S

+1 −0
Original line number Diff line number Diff line
@@ -120,3 +120,4 @@ strcmp_zbb: 
.option pop

#endif

SYM_FUNC_END(strcmp)

EXPORT_SYMBOL(strcmp)

arch/riscv/lib/strlen.S

+1 −0
Original line number Diff line number Diff line
@@ -131,3 +131,4 @@ strlen_zbb: 
#endif

SYM_FUNC_END(strlen)

SYM_FUNC_ALIAS(__pi_strlen, strlen)

EXPORT_SYMBOL(strlen)