[ASan] Add ASan debugging API to get malloc/free stack traces and shadow memory mapping info

Reviewed at http://reviews.llvm.org/D4466




git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@213080 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 86 insertions, 0 deletions

diff --git a/test/asan/TestCases/debug_mapping.cc b/test/asan/TestCases/debug_mapping.cc
new file mode 100644
index 000000000..f96abf6d1
--- /dev/null
+++ b/test/asan/TestCases/debug_mapping.cc
@@ -0,0 +1,24 @@
+// Checks that the debugging API returns correct shadow scale and offset.
+// RUN: %clangxx_asan -O %s -o %t
+// RUN: env ASAN_OPTIONS=verbosity=1 %run %t 2>&1 | FileCheck %s
+
+#include <sanitizer/asan_interface.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+// printed because of verbosity=1
+// CHECK: SHADOW_SCALE: [[SCALE:[0-9]+]]
+// CHECK: SHADOW_OFFSET: [[OFFSET:[0-9]+]]
+
+int main() {
+  size_t scale, offset;
+  __asan_get_shadow_mapping(&scale, &offset);
+
+  fprintf(stderr, "scale: %lx\n", scale);
+  fprintf(stderr, "offset: %lx\n", offset);
+
+  // CHECK: scale: [[SCALE]]
+  // CHECK: offset: [[OFFSET]]
+
+  return 0;
+}
diff --git a/test/asan/TestCases/debug_stacks.cc b/test/asan/TestCases/debug_stacks.cc
new file mode 100644
index 000000000..57bb54650
--- /dev/null
+++ b/test/asan/TestCases/debug_stacks.cc
@@ -0,0 +1,62 @@
+// Check that the stack trace debugging API works and returns correct
+// malloc and free stacks.
+// RUN: %clangxx_asan -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
+
+#include <sanitizer/asan_interface.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+char *mem;
+void func1() {
+  mem = (char *)malloc(10);
+}
+
+void func2() {
+  free(mem);
+}
+
+int main() {
+  func1();
+  func2();
+
+  void *trace[100];
+  size_t num_frames = 100;
+  int thread_id;
+  num_frames = __asan_get_alloc_stack(mem, trace, num_frames, &thread_id);
+
+  fprintf(stderr, "alloc stack retval %s\n", (num_frames > 0 && num_frames < 10)
+          ? "ok" : "");
+  // CHECK: alloc stack retval ok
+  fprintf(stderr, "thread id = %d\n", thread_id);
+  // CHECK: thread id = 0
+  fprintf(stderr, "0x%lx\n", trace[0]);
+  // CHECK: [[ALLOC_FRAME_0:0x[0-9a-f]+]]
+  fprintf(stderr, "0x%lx\n", trace[1]);
+  // CHECK: [[ALLOC_FRAME_1:0x[0-9a-f]+]]
+
+  num_frames = 100;
+  num_frames = __asan_get_free_stack(mem, trace, num_frames, &thread_id);
+
+  fprintf(stderr, "free stack retval %s\n", (num_frames > 0 && num_frames < 10)
+          ? "ok" : "");
+  // CHECK: free stack retval ok
+  fprintf(stderr, "thread id = %d\n", thread_id);
+  // CHECK: thread id = 0
+  fprintf(stderr, "0x%lx\n", trace[0]);
+  // CHECK: [[FREE_FRAME_0:0x[0-9a-f]+]]
+  fprintf(stderr, "0x%lx\n", trace[1]);
+  // CHECK: [[FREE_FRAME_1:0x[0-9a-f]+]]
+
+  mem[0] = 'A'; // BOOM
+
+  // CHECK: ERROR: AddressSanitizer: heap-use-after-free
+  // CHECK: WRITE of size 1 at 0x{{.*}}
+  // CHECK: freed by thread T0 here:
+  // CHECK: #0 [[FREE_FRAME_0]]
+  // CHECK: #1 [[FREE_FRAME_1]]
+  // CHECK: previously allocated by thread T0 here:
+  // CHECK: #0 [[ALLOC_FRAME_0]]
+  // CHECK: #1 [[ALLOC_FRAME_1]]
+
+  return 0;
+}