Use alloc_size attribute on *alloc functions

malloc and family were not declared with __attribute__((alloc_size)).
This was (sometimes) preventing FORTIFY_SOURCE related functions
from knowing the size of the buffer it's dealing with, inhibiting
FORTIFY_SOURCE protections.

Add __attribute__((alloc_size))

Information about the alloc_size attribute can be found
at http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html

Change-Id: Ia2f0a445f0170a7325f69259b5e7fb35a9f14921

1 files changed, 14 insertions, 0 deletions

diff --git a/tests/fortify_test.cpp b/tests/fortify_test.cpp
index 4ea868b..b131fbe 100644
--- a/tests/fortify_test.cpp
+++ b/tests/fortify_test.cpp
@@ -20,6 +20,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/socket.h>
+#include <malloc.h>
 
 // We have to say "DeathTest" here so gtest knows to run this test (which exits)
 // in its own process. Unfortunately, the C preprocessor doesn't give us an
@@ -395,6 +396,19 @@ TEST(DEATHTEST, sprintf_fortified) {
   ASSERT_EXIT(sprintf(buf, "%s", source_buf), testing::KilledBySignal(SIGABRT), "");
 }
 
+#ifndef __clang__
+// This test is disabled in clang because clang doesn't properly detect
+// this buffer overflow. TODO: Fix clang.
+TEST(DEATHTEST, sprintf_malloc_fortified) {
+  ::testing::FLAGS_gtest_death_test_style = "threadsafe";
+  char* buf = (char *) malloc(10);
+  char source_buf[11];
+  memcpy(source_buf, "1234567890", 11);
+  ASSERT_EXIT(sprintf(buf, "%s", source_buf), testing::KilledBySignal(SIGABRT), "");
+  free(buf);
+}
+#endif
+
 TEST(DEATHTEST, sprintf2_fortified) {
   ::testing::FLAGS_gtest_death_test_style = "threadsafe";
   char buf[5];