[PATCH 12/13] powerpc/string: Add KMSAN support
From: Nicholas Miehlbradt <hidden>
Date: 2023-12-14 05:57:08
Also in:
linux-mm, lkml
Subsystem:
kernel selftest framework, kmsan, linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Shuah Khan, Alexander Potapenko, Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
KMSAN expects functions __mem{set,cpy,move} so add aliases pointing to
the respective functions.
Disable use of architecture specific memset{16,32,64} to ensure that
metadata is correctly updated and strn{cpy,cmp} and mem{chr,cmp} which
are implemented in assembly and therefore cannot be instrumented to
propagate/check metadata.
Alias calls to mem{set,cpy,move} to __msan_mem{set,cpy,move} in
instrumented code to correctly propagate metadata.
Signed-off-by: Nicholas Miehlbradt <redacted>
---
arch/powerpc/include/asm/kmsan.h | 7 +++++++
arch/powerpc/include/asm/string.h | 18 ++++++++++++++++--
arch/powerpc/lib/Makefile | 2 ++
arch/powerpc/lib/mem_64.S | 5 ++++-
arch/powerpc/lib/memcpy_64.S | 2 ++
.../selftests/powerpc/copyloops/asm/kmsan.h | 0
.../selftests/powerpc/copyloops/linux/export.h | 1 +
7 files changed, 32 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/powerpc/copyloops/asm/kmsan.h
diff --git a/arch/powerpc/include/asm/kmsan.h b/arch/powerpc/include/asm/kmsan.h
index bc84f6ff2ee9..fc59dc24e170 100644
--- a/arch/powerpc/include/asm/kmsan.h
+++ b/arch/powerpc/include/asm/kmsan.h@@ -7,6 +7,13 @@ #ifndef _ASM_POWERPC_KMSAN_H #define _ASM_POWERPC_KMSAN_H +#ifdef CONFIG_KMSAN +#define EXPORT_SYMBOL_KMSAN(fn) SYM_FUNC_ALIAS(__##fn, fn) \ + EXPORT_SYMBOL(__##fn) +#else +#define EXPORT_SYMBOL_KMSAN(fn) +#endif + #ifndef __ASSEMBLY__ #ifndef MODULE
diff --git a/arch/powerpc/include/asm/string.h b/arch/powerpc/include/asm/string.h
index 60ba22770f51..412626ce619b 100644
--- a/arch/powerpc/include/asm/string.h
+++ b/arch/powerpc/include/asm/string.h@@ -4,7 +4,7 @@ #ifdef __KERNEL__ -#ifndef CONFIG_KASAN +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) #define __HAVE_ARCH_STRNCPY #define __HAVE_ARCH_STRNCMP #define __HAVE_ARCH_MEMCHR
@@ -56,8 +56,22 @@ void *__memmove(void *to, const void *from, __kernel_size_t n); #endif /* CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX */ #endif /* CONFIG_KASAN */ +#ifdef CONFIG_KMSAN + +void *__memset(void *s, int c, __kernel_size_t count); +void *__memcpy(void *to, const void *from, __kernel_size_t n); +void *__memmove(void *to, const void *from, __kernel_size_t n); + +#ifdef __SANITIZE_MEMORY__ +#include <linux/kmsan_string.h> +#define memset __msan_memset +#define memcpy __msan_memcpy +#define memmove __msan_memmove +#endif +#endif /* CONFIG_KMSAN */ + #ifdef CONFIG_PPC64 -#ifndef CONFIG_KASAN +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) #define __HAVE_ARCH_MEMSET32 #define __HAVE_ARCH_MEMSET64
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index 51ad0397c17a..fc3ea3eebbd6 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile@@ -32,9 +32,11 @@ obj-y += code-patching.o feature-fixups.o pmem.o obj-$(CONFIG_CODE_PATCHING_SELFTEST) += test-code-patching.o ifndef CONFIG_KASAN +ifndef CONFIG_KMSAN obj-y += string.o memcmp_$(BITS).o obj-$(CONFIG_PPC32) += strlen_32.o endif +endif obj-$(CONFIG_PPC32) += div64.o copy_32.o crtsavres.o
diff --git a/arch/powerpc/lib/mem_64.S b/arch/powerpc/lib/mem_64.S
index 6fd06cd20faa..a55f2fac49b3 100644
--- a/arch/powerpc/lib/mem_64.S
+++ b/arch/powerpc/lib/mem_64.S@@ -9,8 +9,9 @@ #include <asm/errno.h> #include <asm/ppc_asm.h> #include <asm/kasan.h> +#include <asm/kmsan.h> -#ifndef CONFIG_KASAN +#if !defined(CONFIG_KASAN) && !defined(CONFIG_KMSAN) _GLOBAL(__memset16) rlwimi r4,r4,16,0,15 /* fall through */
@@ -96,6 +97,7 @@ _GLOBAL_KASAN(memset) blr EXPORT_SYMBOL(memset) EXPORT_SYMBOL_KASAN(memset) +EXPORT_SYMBOL_KMSAN(memset) _GLOBAL_TOC_KASAN(memmove) cmplw 0,r3,r4
@@ -140,3 +142,4 @@ _GLOBAL(backwards_memcpy) b 1b EXPORT_SYMBOL(memmove) EXPORT_SYMBOL_KASAN(memmove) +EXPORT_SYMBOL_KMSAN(memmove)
diff --git a/arch/powerpc/lib/memcpy_64.S b/arch/powerpc/lib/memcpy_64.S
index b5a67e20143f..1657861618cc 100644
--- a/arch/powerpc/lib/memcpy_64.S
+++ b/arch/powerpc/lib/memcpy_64.S@@ -8,6 +8,7 @@ #include <asm/asm-compat.h> #include <asm/feature-fixups.h> #include <asm/kasan.h> +#include <asm/kmsan.h> #ifndef SELFTEST_CASE /* For big-endian, 0 == most CPUs, 1 == POWER6, 2 == Cell */
@@ -228,3 +229,4 @@ END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD) #endif EXPORT_SYMBOL(memcpy) EXPORT_SYMBOL_KASAN(memcpy) +EXPORT_SYMBOL_KMSAN(memcpy)
diff --git a/tools/testing/selftests/powerpc/copyloops/asm/kmsan.h b/tools/testing/selftests/powerpc/copyloops/asm/kmsan.h
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/tools/testing/selftests/powerpc/copyloops/linux/export.h b/tools/testing/selftests/powerpc/copyloops/linux/export.h
index e6b80d5fbd14..6379624bbf9b 100644
--- a/tools/testing/selftests/powerpc/copyloops/linux/export.h
+++ b/tools/testing/selftests/powerpc/copyloops/linux/export.h@@ -2,3 +2,4 @@ #define EXPORT_SYMBOL(x) #define EXPORT_SYMBOL_GPL(x) #define EXPORT_SYMBOL_KASAN(x) +#define EXPORT_SYMBOL_KMSAN(x)
--
2.40.1