8302102: Disable ASan for SafeFetch and os::print_hex_dump

Reviewed-by: dholmes, stuefe

src/hotspot/os/posix/safefetch_sigjmp.cpp

@@ -26,6 +26,7 @@
 #include "precompiled.hpp"
 
 #include "runtime/safefetch.hpp"
+#include "sanitizers/address.hpp"
 #include "utilities/debug.hpp"
 #include "utilities/globalDefinitions.hpp"
 
@@ -63,7 +64,7 @@ bool handle_safefetch(int sig, address ignored1, void* ignored2) {
 }
 
 template <class T>
-static bool _SafeFetchXX_internal(const T *adr, T* result) {
+ATTRIBUTE_NO_ASAN static bool _SafeFetchXX_internal(const T *adr, T* result) {
 
   T n = 0;
 

src/hotspot/os/windows/safefetch_windows.hpp

@@ -26,12 +26,13 @@
 #ifndef OS_WINDOWS_SAFEFETCH_WINDOWS_HPP
 #define OS_WINDOWS_SAFEFETCH_WINDOWS_HPP
 
+#include "sanitizers/address.hpp"
 #include "utilities/globalDefinitions.hpp"
 
 // On windows, we use structured exception handling to implement SafeFetch
 
 template <class T>
-inline T SafeFetchXX(const T* adr, T errValue) {
+ATTRIBUTE_NO_ASAN inline T SafeFetchXX(const T* adr, T errValue) {
   T v = 0;
   __try {
     v = *adr;

src/hotspot/share/runtime/os.cpp

@@ -60,6 +60,7 @@
 #include "runtime/threadSMR.hpp"
 #include "runtime/vmOperations.hpp"
 #include "runtime/vm_version.hpp"
+#include "sanitizers/address.hpp"
 #include "services/attachListener.hpp"
 #include "services/mallocTracker.hpp"
 #include "services/mallocHeader.inline.hpp"
@@ -942,6 +943,16 @@ bool os::print_function_and_library_name(outputStream* st,
   return have_function_name || have_library_name;
 }
 
+ATTRIBUTE_NO_ASAN static void print_hex_readable_pointer(outputStream* st, address p,
+                                                         int unitsize) {
+  switch (unitsize) {
+    case 1: st->print("%02x", *(u1*)p); break;
+    case 2: st->print("%04x", *(u2*)p); break;
+    case 4: st->print("%08x", *(u4*)p); break;
+    case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
+  }
+}
+
 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize,
                         int bytes_per_line, address logical_start) {
   assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
@@ -960,12 +971,7 @@ void os::print_hex_dump(outputStream* st, address start, address end, int unitsi
   st->print(PTR_FORMAT ":   ", p2i(logical_p));
   while (p < end) {
     if (is_readable_pointer(p)) {
-      switch (unitsize) {
-        case 1: st->print("%02x", *(u1*)p); break;
-        case 2: st->print("%04x", *(u2*)p); break;
-        case 4: st->print("%08x", *(u4*)p); break;
-        case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
-      }
+      print_hex_readable_pointer(st, p, unitsize);
     } else {
       st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
     }

src/hotspot/share/sanitizers/address.hpp

@@ -29,6 +29,25 @@
 #include <sanitizer/asan_interface.h>
 #endif
 
+// ATTRIBUTE_NO_ASAN
+//
+// Function attribute which informs the compiler to not instrument memory accesses in the function.
+// Useful if the function is known to do something dangerous, such as reading previous stack frames
+// or reading arbitrary regions of memory when dumping during a crash.
+#ifdef ADDRESS_SANITIZER
+#if defined(TARGET_COMPILER_gcc)
+// GCC-like, including Clang.
+#define ATTRIBUTE_NO_ASAN __attribute__((no_sanitize_address))
+#elif defined(TARGET_COMPILER_visCPP)
+// Microsoft Visual C++
+#define ATTRIBUTE_NO_ASAN __declspec(no_sanitize_address)
+#endif
+#endif
+
+#ifndef ATTRIBUTE_NO_ASAN
+#define ATTRIBUTE_NO_ASAN
+#endif
+
 // ASAN_POISON_MEMORY_REGION()/ASAN_UNPOISON_MEMORY_REGION()
 //
 // Poisons/unpoisons the specified memory region. When ASan is available this is the macro of the