Add common interceptors for memchr/memrchr

llvm-svn: 202972

compiler-rt/lib/msan/tests/msan_test.cc

@@ -2059,6 +2059,38 @@ TEST(MemorySanitizer, fcvt) {
   EXPECT_NOT_POISONED(b);
 }
 
+TEST(MemorySanitizer, memchr) {
+  char x[10];
+  break_optimization(x);
+  EXPECT_POISONED(x[0]);
+  x[2] = '2';
+  void *res;
+  EXPECT_UMR(res = memchr(x, '2', 10));
+  EXPECT_NOT_POISONED(res);
+  x[0] = '0';
+  x[1] = '1';
+  res = memchr(x, '2', 10);
+  EXPECT_EQ(&x[2], res);
+  EXPECT_UMR(res = memchr(x, '3', 10));
+  EXPECT_NOT_POISONED(res);
+}
+
+TEST(MemorySanitizer, memrchr) {
+  char x[10];
+  break_optimization(x);
+  EXPECT_POISONED(x[0]);
+  x[9] = '9';
+  void *res;
+  EXPECT_UMR(res = memrchr(x, '9', 10));
+  EXPECT_NOT_POISONED(res);
+  x[0] = '0';
+  x[1] = '1';
+  res = memrchr(x, '0', 2);
+  EXPECT_EQ(&x[0], res);
+  EXPECT_UMR(res = memrchr(x, '7', 10));
+  EXPECT_NOT_POISONED(res);
+}
+
 TEST(MemorySanitizer, frexp) {
   int x;
   x = *GetPoisoned<int>();

compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc

@@ -163,6 +163,34 @@ INTERCEPTOR(int, strncasecmp, const char *s1, const char *s2, SIZE_T n) {
 #define INIT_STRNCASECMP
 #endif
 
+#if SANITIZER_INTERCEPT_MEMCHR
+INTERCEPTOR(void*, memchr, const void *s, int c, SIZE_T n) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, memchr, s, c, n);
+  void *res = REAL(memchr)(s, c, n);
+  uptr len = res ? (char*)res - (char*)s + 1 : n;
+  COMMON_INTERCEPTOR_READ_RANGE(ctx, s, len);
+  return res;
+}
+
+#define INIT_MEMCHR COMMON_INTERCEPT_FUNCTION(memchr)
+#else
+#define INIT_MEMCHR
+#endif
+
+#if SANITIZER_INTERCEPT_MEMRCHR
+INTERCEPTOR(void*, memrchr, const void *s, int c, SIZE_T n) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, memrchr, s, c, n);
+  COMMON_INTERCEPTOR_READ_RANGE(ctx, s, n);
+  return REAL(memrchr)(s, c, n);
+}
+
+#define INIT_MEMRCHR COMMON_INTERCEPT_FUNCTION(memrchr)
+#else
+#define INIT_MEMRCHR
+#endif
+
 #if SANITIZER_INTERCEPT_FREXP
 INTERCEPTOR(double, frexp, double x, int *exp) {
   void *ctx;
@@ -3362,6 +3390,8 @@ INTERCEPTOR(int, capset, void *hdrp, const void *datap) {
   INIT_STRNCMP;                            \
   INIT_STRCASECMP;                         \
   INIT_STRNCASECMP;                        \
+  INIT_MEMCHR;                             \
+  INIT_MEMRCHR;                            \
   INIT_READ;                               \
   INIT_PREAD;                              \
   INIT_PREAD64;                            \

compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h

@@ -50,6 +50,8 @@
 #define SANITIZER_INTERCEPT_STRCMP 1
 #define SANITIZER_INTERCEPT_TEXTDOMAIN SI_LINUX_NOT_ANDROID
 #define SANITIZER_INTERCEPT_STRCASECMP SI_NOT_WINDOWS
+#define SANITIZER_INTERCEPT_MEMCHR 1
+#define SANITIZER_INTERCEPT_MEMRCHR SI_NOT_WINDOWS
 
 #define SANITIZER_INTERCEPT_READ   SI_NOT_WINDOWS
 #define SANITIZER_INTERCEPT_PREAD  SI_NOT_WINDOWS

compiler-rt/lib/tsan/rtl/tsan_interceptors.cc

@@ -632,20 +632,6 @@ TSAN_INTERCEPTOR(int, memcmp, const void *s1, const void *s2, uptr n) {
   return res;
 }
 
-TSAN_INTERCEPTOR(void*, memchr, void *s, int c, uptr n) {
-  SCOPED_TSAN_INTERCEPTOR(memchr, s, c, n);
-  void *res = REAL(memchr)(s, c, n);
-  uptr len = res ? (char*)res - (char*)s + 1 : n;
-  MemoryAccessRange(thr, pc, (uptr)s, len, false);
-  return res;
-}
-
-TSAN_INTERCEPTOR(void*, memrchr, char *s, int c, uptr n) {
-  SCOPED_TSAN_INTERCEPTOR(memrchr, s, c, n);
-  MemoryAccessRange(thr, pc, (uptr)s, n, false);
-  return REAL(memrchr)(s, c, n);
-}
-
 TSAN_INTERCEPTOR(void*, memmove, void *dst, void *src, uptr n) {
   SCOPED_TSAN_INTERCEPTOR(memmove, dst, src, n);
   MemoryAccessRange(thr, pc, (uptr)dst, n, true);
@@ -2162,8 +2148,6 @@ void InitializeInterceptors() {
   TSAN_INTERCEPT(strlen);
   TSAN_INTERCEPT(memset);
   TSAN_INTERCEPT(memcpy);
-  TSAN_INTERCEPT(memchr);
-  TSAN_INTERCEPT(memrchr);
   TSAN_INTERCEPT(memmove);
   TSAN_INTERCEPT(memcmp);
   TSAN_INTERCEPT(strchr);