[msan] Intercept confstr.

llvm-svn: 187412

5 files changed, 35 insertions, 1 deletions

diff --git a/compiler-rt/lib/msan/tests/msan_test.cc b/compiler-rt/lib/msan/tests/msan_test.cc
index a13f05d900d..1890db2b991 100644
--- a/compiler-rt/lib/msan/tests/msan_test.cc
+++ b/compiler-rt/lib/msan/tests/msan_test.cc
@@ -926,6 +926,22 @@ TEST(MemorySanitizer, get_current_dir_name) {
   free(res);
 }
 
+TEST(MemorySanitizer, confstr) {
+  char buf[3];
+  size_t res = confstr(_CS_PATH, buf, sizeof(buf));
+  ASSERT_GT(res, sizeof(buf));
+  EXPECT_NOT_POISONED(buf[0]);
+  EXPECT_NOT_POISONED(buf[sizeof(buf) - 1]);
+
+  char buf2[1000];
+  res = confstr(_CS_PATH, buf2, sizeof(buf2));
+  ASSERT_LT(res, sizeof(buf2));
+  EXPECT_NOT_POISONED(buf2[0]);
+  EXPECT_NOT_POISONED(buf2[res - 1]);
+  EXPECT_POISONED(buf2[res]);
+  ASSERT_EQ(res, strlen(buf2) + 1);
+}
+
 TEST(MemorySanitizer, readdir) {
   DIR *dir = opendir(".");
   struct dirent *d = readdir(dir);
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
index e48b3922289..58dd044d309 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -1747,6 +1747,20 @@ INTERCEPTOR(char *, canonicalize_file_name, const char *path) {
 #define INIT_CANONICALIZE_FILE_NAME
 #endif
 
+#if SANITIZER_INTERCEPT_CONFSTR
+INTERCEPTOR(SIZE_T, confstr, int name, char *buf, SIZE_T len) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, confstr, name, buf, len);
+  SIZE_T res = REAL(confstr)(name, buf, len);
+  if (buf && res)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buf, res < len ? res : len);
+  return res;
+}
+#define INIT_CONFSTR INTERCEPT_FUNCTION(confstr);
+#else
+#define INIT_CONFSTR
+#endif
+
 #define SANITIZER_COMMON_INTERCEPTORS_INIT \
   INIT_STRCMP;                             \
   INIT_STRNCMP;                            \
@@ -1805,4 +1819,5 @@ INTERCEPTOR(char *, canonicalize_file_name, const char *path) {
   INIT_WCSNRTOMBS;                         \
   INIT_TCGETATTR;                          \
   INIT_REALPATH;                           \
-  INIT_CANONICALIZE_FILE_NAME;
+  INIT_CANONICALIZE_FILE_NAME;             \
+  INIT_CONFSTR;
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
index e07a134e169..a601c7f0054 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
@@ -109,5 +109,6 @@
 # define SANITIZER_INTERCEPT_TCGETATTR SI_LINUX
 # define SANITIZER_INTERCEPT_REALPATH SI_NOT_WINDOWS
 # define SANITIZER_INTERCEPT_CANONICALIZE_FILE_NAME SI_LINUX_NOT_ANDROID
+# define SANITIZER_INTERCEPT_CONFSTR SI_MAC || SI_LINUX_NOT_ANDROID
 
 #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H
diff --git a/compiler-rt/lib/tsan/rtl/tsan_stat.cc b/compiler-rt/lib/tsan/rtl/tsan_stat.cc
index 5e8cc18ee79..fe0c09cf1f9 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_stat.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_stat.cc
@@ -352,6 +352,7 @@ void StatOutput(u64 *stat) {
   name[StatInt_tcgetattr]                = "  tcgetattr                       ";
   name[StatInt_realpath]                 = "  realpath                        ";
   name[StatInt_canonicalize_file_name]   = "  canonicalize_file_name          ";
+  name[StatInt_confstr]                  = "  confstr                         ";
 
   name[StatAnnotation]                   = "Dynamic annotations               ";
   name[StatAnnotateHappensBefore]        = "  HappensBefore                   ";
diff --git a/compiler-rt/lib/tsan/rtl/tsan_stat.h b/compiler-rt/lib/tsan/rtl/tsan_stat.h
index 6131721537a..606ee66e759 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_stat.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_stat.h
@@ -347,6 +347,7 @@ enum StatType {
   StatInt_tcgetattr,
   StatInt_realpath,
   StatInt_canonicalize_file_name,
+  StatInt_confstr,
 
   // Dynamic annotations.
   StatAnnotation,