Changeset 2f7d77c6 in mainline

Timestamp:

2018-06-14T19:02:26Z (6 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.

Files:

• HelenOS.config (modified) (1 diff)
• kernel/Makefile (modified) (2 diffs)
• kernel/generic/include/lib/memfnc.h (modified) (1 diff)
• kernel/generic/include/mem.h (modified) (1 diff)
• kernel/generic/src/lib/memfnc.c (modified) (1 diff)
• kernel/generic/src/lib/ubsan.c (added)
• uspace/Makefile.common (modified) (1 diff)
• uspace/lib/c/Makefile (modified) (1 diff)
• uspace/lib/c/generic/ubsan.c (added)
• uspace/srv/fs/fat/fat_fat.c (modified) (1 diff)

HelenOS.config

@@ -379 +379 @@
 ! CONFIG_DEBUG (y/n)
 
+% Sanitize undefined behavior (userspace)
+! CONFIG_UBSAN (n/y)
+
+% Sanitize undefined behavior (kernel)
+! CONFIG_UBSAN_KERNEL (n/y)
+
 % Deadlock detection support for spinlocks
 ! [CONFIG_DEBUG=y&CONFIG_SMP=y] CONFIG_DEBUG_SPINLOCK (y/n)

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;
+}
+
 /** @}
  */

uspace/Makefile.common

@@ -190 +190 @@
 endif
 
+ifeq ($(CONFIG_UBSAN),y)
+        DEFAULT_CFLAGS += -fsanitize=undefined
+endif
+
 ifeq ($(COMPILER),clang)
         DEFAULT_CFLAGS += \

uspace/lib/c/Makefile

@@ -165 +165 @@
         generic/pio_trace.c \
         generic/qsort.c \
+        generic/ubsan.c \
         generic/uuid.c \
         generic/vbd.c \

uspace/srv/fs/fat/fat_fat.c

@@ -967 +967 @@
                  */
                 if (!FAT_IS_FAT12(bs) &&
-                    ((e0 >> 8) != (FAT_MASK(bs) >> 8) || e1 != FAT_MASK(bs)))
+                    ((e0 >> 8) != ((fat_cluster_t) FAT_MASK(bs) >> 8) || e1 != FAT_MASK(bs)))
                         return ENOTSUP;
         }