asan.c (instrument_strlen_call): Fixed instrumentation of trailing byte.

2014-06-18  Yury Gribov  <y.gribov@samsung.com>

gcc/
	* asan.c (instrument_strlen_call): Fixed instrumentation of
	trailing byte.

gcc/testsuite/
	* c-c++-common/asan/strlen-overflow-1.c: New test.

Co-Authored-By: Max Ostapenko <m.ostapenko@partner.samsung.com>

From-SVN: r211849

1 files changed, 29 insertions, 0 deletions

diff --git a/gcc/testsuite/c-c++-common/asan/strlen-overflow-1.c b/gcc/testsuite/c-c++-common/asan/strlen-overflow-1.c
new file mode 100644
index 0000000..bf6bf66
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/asan/strlen-overflow-1.c
@@ -0,0 +1,29 @@
+/* { dg-do run } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+/* { dg-shouldfail "asan" } */
+
+#include <sanitizer/asan_interface.h>
+
+char a[2] = "0";
+
+#ifdef __cplusplus
+extern "C"
+#endif
+
+__attribute__((no_sanitize_address, noinline)) __SIZE_TYPE__
+strlen (const char *p) {
+
+  __SIZE_TYPE__ n = 0;
+  for (; *p; ++n, ++p);
+  return n;
+}
+
+int main () {
+  char *p = &a[0];
+  asm ("" : "+r"(p));
+  __asan_poison_memory_region ((char *)&a[1], 1);
+  return __builtin_strlen (a);
+}
+
+/* { dg-output "READ of size 1 at 0x\[0-9a-f\]+ thread T0.*(\n|\r\n|\r)" } */
+/* { dg-output "    #0 0x\[0-9a-f\]+ (in _*main (\[^\n\r]*strlen-overflow-1.c:24|\[^\n\r]*:0)|\[(\]).*(\n|\r\n|\r)" } */