[msan] Intercept memccpy.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193897 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 58 insertions, 0 deletions

diff --git a/lib/msan/msan_interceptors.cc b/lib/msan/msan_interceptors.cc
index b96e4b3f..de22f850 100644
--- a/lib/msan/msan_interceptors.cc
+++ b/lib/msan/msan_interceptors.cc
@@ -120,6 +120,16 @@ INTERCEPTOR(void *, mempcpy, void *dest, const void *src, SIZE_T n) {
   return (char *)__msan_memcpy(dest, src, n) + n;
 }
 
+INTERCEPTOR(void *, memccpy, void *dest, const void *src, int c, SIZE_T n) {
+  ENSURE_MSAN_INITED();
+  void *res = REAL(memccpy)(dest, src, c, n);
+  CHECK(!res || (res >= dest && res <= (char *)dest + n));
+  SIZE_T sz = res ? (char *)res - (char *)dest : n;
+  CHECK_UNPOISONED(src, sz);
+  __msan_unpoison(dest, sz);
+  return res;
+}
+
 INTERCEPTOR(void *, memmove, void *dest, const void *src, SIZE_T n) {
   return __msan_memmove(dest, src, n);
 }
@@ -1428,6 +1438,7 @@ void InitializeInterceptors() {
   INTERCEPT_FUNCTION(fread_unlocked);
   INTERCEPT_FUNCTION(readlink);
   INTERCEPT_FUNCTION(memcpy);
+  INTERCEPT_FUNCTION(memccpy);
   INTERCEPT_FUNCTION(mempcpy);
   INTERCEPT_FUNCTION(memset);
   INTERCEPT_FUNCTION(memmove);
diff --git a/lib/msan/tests/msan_test.cc b/lib/msan/tests/msan_test.cc
index ab109874..c387567d 100644
--- a/lib/msan/tests/msan_test.cc
+++ b/lib/msan/tests/msan_test.cc
@@ -1318,6 +1318,53 @@ TEST(MemorySanitizer, memmove) {
   EXPECT_POISONED(y[1]);
 }
 
+TEST(MemorySanitizer, memccpy_nomatch) {
+  char* x = new char[5];
+  char* y = new char[5];
+  strcpy(x, "abc");
+  memccpy(y, x, 'd', 4);
+  EXPECT_NOT_POISONED(y[0]);
+  EXPECT_NOT_POISONED(y[1]);
+  EXPECT_NOT_POISONED(y[2]);
+  EXPECT_NOT_POISONED(y[3]);
+  EXPECT_POISONED(y[4]);
+  delete[] x;
+  delete[] y;
+}
+
+TEST(MemorySanitizer, memccpy_match) {
+  char* x = new char[5];
+  char* y = new char[5];
+  strcpy(x, "abc");
+  memccpy(y, x, 'b', 4);
+  EXPECT_NOT_POISONED(y[0]);
+  EXPECT_NOT_POISONED(y[1]);
+  EXPECT_POISONED(y[2]);
+  EXPECT_POISONED(y[3]);
+  EXPECT_POISONED(y[4]);
+  delete[] x;
+  delete[] y;
+}
+
+TEST(MemorySanitizer, memccpy_nomatch_positive) {
+  char* x = new char[5];
+  char* y = new char[5];
+  strcpy(x, "abc");
+  EXPECT_UMR(memccpy(y, x, 'd', 5));
+  delete[] x;
+  delete[] y;
+}
+
+TEST(MemorySanitizer, memccpy_match_positive) {
+  char* x = new char[5];
+  char* y = new char[5];
+  x[0] = 'a';
+  x[2] = 'b';
+  EXPECT_UMR(memccpy(y, x, 'b', 5));
+  delete[] x;
+  delete[] y;
+}
+
 TEST(MemorySanitizer, bcopy) {
   char* x = new char[2];
   char* y = new char[2];