Add __lsan::ScopedInterceptorDisabler for strerror(3)

[krytarowski]

Summary

strerror(3) on NetBSD uses internally TSD with a destructor that is never
fired for exit(3). It's correctly called for pthread_exit(3) scenarios.

This is a case when a leak on exit(3) is expected, unavoidable and harmless.

[krytarowski]

• restrict __lsan::ScopedInterceptorDisabler to ASan and LSan

[vitalybuka]

lib/asan/asan_interceptors.cpp

256

could you please add this into sanitizer_common/
#ifndef COMMON_INTERCEPTOR_STRERROR
#define COMMON_INTERCEPTOR_STRERROR() {}
#endif

and define in asan and msan
#if NETBSD
#define COMMON_INTERCEPTOR_STRERROR() __lsan::ScopedInterceptorDisabler;
#fi

[krytarowski]

• apply changes from review

[vitalybuka]

lib/lsan/lsan_interceptors.cpp

348

Why this one can't use COMMON_INTERCEPTOR_STRERROR?

[krytarowski]

lib/lsan/lsan_interceptors.cpp

348

sanitizer_common_interceptors.inc is not included in LSan.

Including it exceeds this patch scope.

lib/asan/asan_interceptors.cpp

#define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
   } while (false)
 
 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
   do {                                                      \
     ASAN_INTERCEPTOR_ENTER(ctx, memset);                    \
     ASAN_MEMSET_IMPL(ctx, block, c, size);                  \
   } while (false)
 
+#undef SANITIZER_INTERCEPT_STRERROR
+
 #include "sanitizer_common/sanitizer_common_interceptors.inc"
 #include "sanitizer_common/sanitizer_signal_interceptors.inc"
 
 // Syscall interceptors don't have contexts, we don't support suppressions
 // for them.
 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) ASAN_READ_RANGE(nullptr, p, s)
 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) ASAN_WRITE_RANGE(nullptr, p, s)
 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \

 
 INTERCEPTOR(int, pthread_join, void *t, void **arg) {
   return real_pthread_join(t, arg);
 }
 
 DEFINE_REAL_PTHREAD_FUNCTIONS
 #endif  // ASAN_INTERCEPT_PTHREAD_CREATE
 
+#if SANITIZER_INTERCEPT_STRERROR
+INTERCEPTOR(char *, strerror, int errnum) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, strerror, errnum);
+#if CAN_SANITIZE_LEAKS
+  __lsan::ScopedInterceptorDisabler disabler;
+#endif
+  char *res = REAL(strerror)(errnum);
+  if (res) COMMON_INTERCEPTOR_INITIALIZE_RANGE(res, REAL(strlen)(res) + 1);
+  return res;
+}
+#endif
+
 #if ASAN_INTERCEPT_SWAPCONTEXT
 static void ClearShadowMemoryForContextStack(uptr stack, uptr ssize) {
   // Align to page size.
   uptr PageSize = GetPageSizeCached();
   uptr bottom = stack & ~(PageSize - 1);
   ssize += stack - bottom;
   ssize = RoundUpTo(ssize, PageSize);
   static const uptr kMaxSaneContextStackSize = 1 << 22;  // 4 Mb

 #endif
 
   // Intecept jump-related functions.
   ASAN_INTERCEPT_FUNC(longjmp);
 
 #if ASAN_INTERCEPT_SWAPCONTEXT
   ASAN_INTERCEPT_FUNC(swapcontext);
 #endif
+#if SANITIZER_INTERCEPT_STRERROR
+  ASAN_INTERCEPT_FUNC(strerror);
+#endif
 #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);

lib/lsan/lsan_interceptors.cpp

INTERCEPTOR(void, thr_exit, tid_t *state) {
   ThreadFinish();
   REAL(thr_exit)(state);
 }
 #define LSAN_MAYBE_INTERCEPT_THR_EXIT INTERCEPT_FUNCTION(thr_exit)
 #else
 #define LSAN_MAYBE_INTERCEPT_THR_EXIT
 #endif
 
+#if SANITIZER_NETBSD
+INTERCEPTOR(char *, strerror, int errnum) {
+  __lsan::ScopedInterceptorDisabler disabler;
+  return REAL(strerror)(errnum);
+}
+#define LSAN_MAYBE_INTERCEPT_STRERROR INTERCEPT_FUNCTION(strerror)
+#else
+#define LSAN_MAYBE_INTERCEPT_STRERROR
+#endif
+
 struct ThreadParam {
   void *(*callback)(void *arg);
   void *param;
   atomic_uintptr_t tid;
 };
 
 extern "C" void *__lsan_thread_start_func(void *arg) {
   ThreadParam *p = (ThreadParam*)arg;
void InitializeInterceptors() {
   LSAN_MAYBE_INTERCEPT_MALLOPT;
   INTERCEPT_FUNCTION(pthread_create);
   INTERCEPT_FUNCTION(pthread_join);
   INTERCEPT_FUNCTION(_exit);
 
   LSAN_MAYBE_INTERCEPT__LWP_EXIT;
   LSAN_MAYBE_INTERCEPT_THR_EXIT;
 
+  LSAN_MAYBE_INTERCEPT_STRERROR;
+
 #if !SANITIZER_NETBSD && !SANITIZER_FREEBSD
   if (pthread_key_create(&g_thread_finalize_key, &thread_finalize)) {
     Report("LeakSanitizer: failed to create thread key.\n");
     Die();
   }
 #endif
 }
 
 } // namespace __lsan