Fixing a possible freeze on abort with 'v8_win64_unwinding_info'

paolosevMSFT · Commit Bot · commit 3a75c1fb577d · 2019-05-28T00:43:08.000Z
Win64 unwind data can specify a language-specific handler function which is called as part of the search for an exception handler, as described in https://docs.microsoft.com/en-us/cpp/build/exception-handling-x64?view=vs-2019. This is used for example by Crashpad to register its own exception handler for exceptions in V8-generated code. There is a problem in the code that may cause a freeze on abort: in file \deps\v8\src\unwinding-info-win64.cc in function CRASH_HANDLER_FUNCTION_NAME the line: return EXCEPTION_CONTINUE_SEARCH; should be return ExceptionContinueSearch; These constants are both used in the context of Win32 exception handlers, but they have different semantics and unfortunately different values: EXCEPTION_CONTINUE_SEARCH (=0) should be returned by an exception filter while a language-specific handler should return an EXCEPTION_DISPOSITION value, and more precisely ExceptionContinueSearch (=1) in this case. Bug: v8:9295 Change-Id: I1a3aaabf357e52a909611814f1ea013cf652ae06 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1629795 Reviewed-by: Jakob Kummerow <jkummerow@chromium.org> Commit-Queue: Paolo Severini <paolosev@microsoft.com> Cr-Commit-Position: refs/heads/master@{#61867}
diff --git a/src/diagnostics/unwinding-info-win64.cc b/src/diagnostics/unwinding-info-win64.cc
@@ -107,7 +107,7 @@ extern "C" __declspec(dllexport) int CRASH_HANDLER_FUNCTION_NAME(
     EXCEPTION_POINTERS info = {ExceptionRecord, ContextRecord};
     return unhandled_exception_callback_g(&info);
   }
-  return EXCEPTION_CONTINUE_SEARCH;
+  return ExceptionContinueSearch;
 }
 
 static constexpr int kMaxExceptionThunkSize = 12;

Original file line number	Diff line number	Diff line change
`@@ -107,7 +107,7 @@ extern "C" __declspec(dllexport) int CRASH_HANDLER_FUNCTION_NAME(`
`107`	`107`	`EXCEPTION_POINTERS info = {ExceptionRecord, ContextRecord};`
`108`	`108`	`return unhandled_exception_callback_g(&info);`
`109`	`109`	`}`
`110`		`- return EXCEPTION_CONTINUE_SEARCH;`
	`110`	`+ return ExceptionContinueSearch;`
`111`	`111`	`}`
`112`	`112`
`113`	`113`	`static constexpr int kMaxExceptionThunkSize = 12;`