Changeset 2f7d77c6 in mainline for kernel

Timestamp:

2018-06-14T19:02:26Z (7 years ago)

Author:

Jiří Zárevúcky <jiri.zarevucky@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

587478b

Parents:

abf8bd8

git-author:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-06-14 17:48:39)

git-committer:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-06-14 19:02:26)

Message:

Add rudimentary support for undefined behavior sanitizer.

Location:

kernel

Files:

• Makefile (modified) (2 diffs)
• generic/include/lib/memfnc.h (modified) (1 diff)
• generic/include/mem.h (modified) (1 diff)
• generic/src/lib/memfnc.c (modified) (1 diff)
• generic/src/lib/ubsan.c (added)

kernel/Makefile

@@ -106 +106 @@
 ifeq ($(CONFIG_DEBUG),y)
         COMMON_CFLAGS += -Werror
+endif
+
+ifeq ($(CONFIG_UBSAN_KERNEL),y)
+        COMMON_CFLAGS += -fsanitize=undefined
 endif
 
@@ -209 +213 @@
         generic/src/lib/ra.c \
         generic/src/lib/rd.c \
+        generic/src/lib/ubsan.c \
         generic/src/printf/printf_core.c \
         generic/src/printf/printf.c \

kernel/generic/include/lib/memfnc.h

@@ -51 +51 @@
     __attribute__((nonnull(1, 2)))
     ATTRIBUTE_OPTIMIZE("-fno-tree-loop-distribute-patterns") DO_NOT_DISCARD;
+extern int memcmp(const void *, const void *, size_t len)
+    __attribute__((nonnull(1, 2)))
+    ATTRIBUTE_OPTIMIZE("-fno-tree-loop-distribute-patterns") DO_NOT_DISCARD;
 
 #define alloca(size) __builtin_alloca((size))

kernel/generic/include/mem.h

@@ -48 +48 @@
 #define memset(dst, val, cnt)  __builtin_memset((dst), (val), (cnt))
 #define memcpy(dst, src, cnt)  __builtin_memcpy((dst), (src), (cnt))
+#define memcmp(s1, s2, cnt)    __builtin_memcmp((s1), (s2), (cnt))
 
 extern void memsetb(void *, size_t, uint8_t)

kernel/generic/src/lib/memfnc.c

@@ -87 +87 @@
 }
 
+/** Compare two memory areas.
+ *
+ * @param s1  Pointer to the first area to compare.
+ * @param s2  Pointer to the second area to compare.
+ * @param len Size of the areas in bytes.
+ *
+ * @return Zero if areas have the same contents. If they differ,
+ *         the sign of the result is the same as the sign of the
+ *         difference of the first pair of different bytes.
+ *
+ */
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+        uint8_t *u1 = (uint8_t *) s1;
+        uint8_t *u2 = (uint8_t *) s2;
+        size_t i;
+
+        for (i = 0; i < len; i++) {
+                if (*u1 != *u2)
+                        return (int)(*u1) - (int)(*u2);
+                ++u1;
+                ++u2;
+        }
+
+        return 0;
+}
+
 /** @}
  */