s390/kasan: replace some memory functions

Follow the common kasan approach:

    "KASan replaces memory functions with manually instrumented
    variants.  Original functions declared as weak symbols so strong
    definitions in mm/kasan/kasan.c could replace them. Original
    functions have aliases with '__' prefix in name, so we could call
    non-instrumented variant if needed."

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/arch/s390/include/asm/string.h b/arch/s390/include/asm/string.h
index 50f26fc9acb2..116cc15a4b8a 100644
--- a/arch/s390/include/asm/string.h
+++ b/arch/s390/include/asm/string.h
@@ -53,6 +53,27 @@ char *strstr(const char *s1, const char *s2);
 #undef __HAVE_ARCH_STRSEP
 #undef __HAVE_ARCH_STRSPN
 
+#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
+
+extern void *__memcpy(void *dest, const void *src, size_t n);
+extern void *__memset(void *s, int c, size_t n);
+extern void *__memmove(void *dest, const void *src, size_t n);
+
+/*
+ * For files that are not instrumented (e.g. mm/slub.c) we
+ * should use not instrumented version of mem* functions.
+ */
+
+#define memcpy(dst, src, len) __memcpy(dst, src, len)
+#define memmove(dst, src, len) __memmove(dst, src, len)
+#define memset(s, c, n) __memset(s, c, n)
+
+#ifndef __NO_FORTIFY
+#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
+#endif
+
+#endif /* defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) */
+
 void *__memset16(uint16_t *s, uint16_t v, size_t count);
 void *__memset32(uint32_t *s, uint32_t v, size_t count);
 void *__memset64(uint64_t *s, uint64_t v, size_t count);