[ASAN] Add interceptor for __longjmp_chk

Summary:
glibc on Linux calls __longjmp_chk instead of longjmp (or _longjmp) when
_FORTIFY_SOURCE is defined. Ensure that an ASAN-instrumented program
intercepts this function when a system library calls it, otherwise the
stack might remain poisoned and result in CHECK failures and false
positives.

Fixes https://github.com/google/sanitizers/issues/721

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D32408

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@302152 91177308-0d34-0410-b5e6-96231b3b80d8
Change-Id: I756e6a66139bc4ee95d3af1be792b025efe39ce0

diff --git a/libsanitizer/asan/asan_interceptors.cc b/libsanitizer/asan/asan_interceptors.cc
index 743abe5..49c9fef 100644 (file)
--- a/libsanitizer/asan/asan_interceptors.cc
+++ b/libsanitizer/asan/asan_interceptors.cc
@@ -372,6 +372,13 @@ INTERCEPTOR(void, _longjmp, void *env, int val) {
 }
 #endif
 
+#if ASAN_INTERCEPT___LONGJMP_CHK
+INTERCEPTOR(void, __longjmp_chk, void *env, int val) {
+  __asan_handle_no_return();
+  REAL(__longjmp_chk)(env, val);
+}
+#endif
+
 #if ASAN_INTERCEPT_SIGLONGJMP
 INTERCEPTOR(void, siglongjmp, void *env, int val) {
   __asan_handle_no_return();
@@ -770,6 +777,9 @@ void InitializeAsanInterceptors() {
 #if ASAN_INTERCEPT__LONGJMP
   ASAN_INTERCEPT_FUNC(_longjmp);
 #endif
+#if ASAN_INTERCEPT___LONGJMP_CHK
+  ASAN_INTERCEPT_FUNC(__longjmp_chk);
+#endif
 #if ASAN_INTERCEPT_SIGLONGJMP
   ASAN_INTERCEPT_FUNC(siglongjmp);
 #endif

diff --git a/libsanitizer/asan/asan_interceptors.h b/libsanitizer/asan/asan_interceptors.h
index 7053bb7..565a632 100644 (file)
--- a/libsanitizer/asan/asan_interceptors.h
+++ b/libsanitizer/asan/asan_interceptors.h
@@ -56,6 +56,12 @@
 # define ASAN_INTERCEPT_SIGLONGJMP 0
 #endif
 
+#if SANITIZER_LINUX && !SANITIZER_ANDROID
+# define ASAN_INTERCEPT___LONGJMP_CHK 1
+#else
+# define ASAN_INTERCEPT___LONGJMP_CHK 0
+#endif
+
 // Android bug: https://code.google.com/p/android/issues/detail?id=61799
 #if ASAN_HAS_EXCEPTIONS && !SANITIZER_WINDOWS && \
     !(SANITIZER_ANDROID && defined(__i386))