TestCase null_deref was failing in Win64:

bergeret · bergeret · commit 3d89db445d1f · 2016-07-15T17:16:37.000Z
c:\lipo\work\asan\b_llvm>c:\lipo\work\asan\b_llvm\projects\compiler-rt\test\asan\X86_64WindowsConfig\TestCases\Output\null_deref.cc.tmp ================================================================= ==5488==ERROR: AddressSanitizer: access-violation on unknown address 0x000000000028 (pc 0x7ff701f91067 bp 0x000c8cf8fbf0 sp 0x000c8cf8fbb0 T0) ==5488==The signal is caused by a READ memory access. ==5488==Hint: address points to the zero page. #0 0x7ff701f91066 in NullDeref(int *) C:\lipo\work\asan\llvm\projects\compiler-rt\test\asan\TestCases\null_deref.cc:15:10 #1 0x8a0388830a67 (<unknown module>) The reason was symbols was not initilized. In fact, it was first inited with a call to stack.Print(), which calls WinSymbolizerTool::SymbolizePC, then InitializeDbgHelpIfNeeded(). Since the StackWalk was performed before the stack.Print(), stack frames where not gathered correctly. There should be a better place to initialize symbols. For now, this patch makes the test happy. Patch by Wei Wang Differential Revision: https://reviews.llvm.org/D22410 llvm-svn: 275580
diff --git a/compiler-rt/lib/interception/interception_win.cc b/compiler-rt/lib/interception/interception_win.cc
@@ -410,7 +410,6 @@ static size_t GetInstructionSize(uptr address) {
 
     case 0xb8:  // b8 XX XX XX XX : mov eax, XX XX XX XX
     case 0xB9:  // b9 XX XX XX XX : mov ecx, XX XX XX XX
-    case 0xA1:  // A1 XX XX XX XX : mov eax, dword ptr ds:[XXXXXXXX]
       return 5;
 
     // Cannot overwrite control-instruction. Return 0 to indicate failure.
@@ -453,6 +452,11 @@ static size_t GetInstructionSize(uptr address) {
   }
 
 #if SANITIZER_WINDOWS64
+  switch (*(u8*)address) {
+    case 0xA1:  // A1 XX XX XX XX XX XX XX XX :
+                //   movabs eax, dword ptr ds:[XXXXXXXX]
+      return 8;
+  }
   switch (*(u16*)address) {
     case 0x5040:  // push rax
     case 0x5140:  // push rcx
@@ -500,7 +504,12 @@ static size_t GetInstructionSize(uptr address) {
                       //   mov rax, QWORD PTR [rip + XXXXXXXX]
     case 0x25ff48:    // 48 ff 25 XX XX XX XX :
                       //   rex.W jmp QWORD PTR [rip + XXXXXXXX]
-      return 7;
+      // Instructions having offset relative to 'rip' cannot be copied.
+      return 0;
+
+    case 0x2444c7:    // C7 44 24 XX YY YY YY YY
+                      //   mov dword ptr [rsp + XX], YYYYYYYY
+      return 8;
   }
 
   switch (*(u32*)(address)) {
@@ -512,7 +521,10 @@ static size_t GetInstructionSize(uptr address) {
   }
 
 #else
-
+  switch (*(u8*)address) {
+    case 0xA1:  // A1 XX XX XX XX :  mov eax, dword ptr ds:[XXXXXXXX]
+      return 5;
+  }
   switch (*(u16*)address) {
     case 0x458B:  // 8B 45 XX : mov eax, dword ptr [ebp + XX]
     case 0x5D8B:  // 8B 5D XX : mov ebx, dword ptr [ebp + XX]
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
@@ -177,6 +177,10 @@ class Symbolizer final {
   };
 };
 
+#ifdef SANITIZER_WINDOWS
+void InitializeDbgHelpIfNeeded();
+#endif
+
 }  // namespace __sanitizer
 
 #endif  // SANITIZER_SYMBOLIZER_H
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cc b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cc
@@ -42,6 +42,8 @@ bool TrySymInitialize() {
   // FIXME: We don't call SymCleanup() on exit yet - should we?
 }
 
+}  // namespace
+
 // Initializes DbgHelp library, if it's not yet initialized. Calls to this
 // function should be synchronized with respect to other calls to DbgHelp API
 // (e.g. from WinSymbolizerTool).
@@ -97,8 +99,6 @@ void InitializeDbgHelpIfNeeded() {
   }
 }
 
-}  // namespace
-
 bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
   InitializeDbgHelpIfNeeded();
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win.cc b/compiler-rt/lib/sanitizer_common/sanitizer_win.cc
@@ -28,6 +28,7 @@
 #include "sanitizer_mutex.h"
 #include "sanitizer_placement_new.h"
 #include "sanitizer_stacktrace.h"
+#include "sanitizer_symbolizer.h"
 
 namespace __sanitizer {
 
@@ -733,6 +734,9 @@ void BufferedStackTrace::SlowUnwindStackWithContext(uptr pc, void *context,
   CONTEXT ctx = *(CONTEXT *)context;
   STACKFRAME64 stack_frame;
   memset(&stack_frame, 0, sizeof(stack_frame));
+
+  InitializeDbgHelpIfNeeded();
+
   size = 0;
 #if defined(_WIN64)
   int machine_type = IMAGE_FILE_MACHINE_AMD64;

Original file line number	Diff line number	Diff line change
`@@ -42,6 +42,8 @@ bool TrySymInitialize() {`
`42`	`42`	`// FIXME: We don't call SymCleanup() on exit yet - should we?`
`43`	`43`	`}`
`44`	`44`
	`45`	`+} // namespace`
	`46`	`+`
`45`	`47`	`// Initializes DbgHelp library, if it's not yet initialized. Calls to this`
`46`	`48`	`// function should be synchronized with respect to other calls to DbgHelp API`
`47`	`49`	`// (e.g. from WinSymbolizerTool).`
`@@ -97,8 +99,6 @@ void InitializeDbgHelpIfNeeded() {`
`97`	`99`	`}`
`98`	`100`	`}`
`99`	`101`
`100`		`-} // namespace`
`101`		`-`
`102`	`102`	`bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {`
`103`	`103`	`InitializeDbgHelpIfNeeded();`
`104`	`104`