[asan] Remove allow_user_segv_handler on Windows.

[vitalybuka]

Summary

This flags is not covered by tests on Windows and looks like it's implemented
incorrectly. Switching its default breaks some tests.

Taking into account that related handle_segv flag is not supported on Windows
it's safer to remove it until we commit to support it.

[vitalybuka]

FYI: I'd like to land https://reviews.llvm.org/D32443, but flipping allow_user_segv_handler to true breaks windows tests: http://lab.llvm.org:8011/builders/sanitizer-windows/builds/11603/steps/run%20fuzzer%20tests/logs/stdio

[zturner]

This seems ok to me, especially since there is no test coverage for it on Windows. rnk@, any thoughts?

[rnk]

This is unfortunate. I want WinASan to behave as much like Linux ASan as possible. The problem is that the MSVC CRT always registers an unhandled exception filter, so we have to overwrite the "user" segv handler if we want ASan to work properly (i.e. catch null derefs) by default.

Anyway, go for it. All the users that we care about (Chrome) manually install ASan's unhandled exception filter for us, so we don't have to fight over which registration wins: https://cs.chromium.org/chromium/src/third_party/crashpad/crashpad/client/crashpad_client_win.cc?type=cs&q=crashpad+asan+package:%5Echromium$&l=119

[rnk]

lgtm

[thakis]

Either this or the reland of making allow_user_segv_handler to true broke this test on Windows:

lit.py: E:/b/build/slave/win_upload_clang/build/src/third_party/llvm/tools/clang/test/lit.cfg:200: note: using clang: 'E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.EXE'
-- Testing: 33069 tests, 8 threads --
Testing: 0 .. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90.
FAIL: UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp (31844 of 33069)
******************** TEST 'UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp' FAILED ********************
Script:
--
E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.exe  -fms-compatibility-version=19.00.24213.1 -fsanitize=signed-integer-overflow E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp -o E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp1 &&  E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp1 2>&1 | FileCheck E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp --check-prefix=CHECKS
E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.exe  -fms-compatibility-version=19.00.24213.1 -fsanitize=unsigned-integer-overflow E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp -o E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp2 &&  E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp2 2>&1 | FileCheck E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp --check-prefix=CHECKU
--
Exit Code: -2147483648
Command Output (stdout):
--
$ "E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.exe" "-fms-compatibility-version=19.00.24213.1" "-fsanitize=signed-integer-overflow" "E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp" "-o" "E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp1"
# command output:
   Creating library E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.lib and object E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.exp
# command stderr:
E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp:8:3: warning: expression result unused [-Wunused-value]
  -unsigned(-0x7fffffff - 1); // ok
  ^~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
$ "E:\b\build\slave\win_upload_clang\build\src\third_party\llvm-bootstrap\projects\compiler-rt\test\ubsan\Standalone-x86_64\TestCases\Integer\Output\negate-overflow.cpp.tmp1"
note: command had no output on stdout or stderr
error: command failed with exit status: 0x80000000
$ "FileCheck" "E:\b\build\slave\win_upload_clang\build\src\third_party\llvm\projects\compiler-rt\test\ubsan\TestCases\Integer\negate-overflow.cpp" "--check-prefix=CHECKS"
--

Please take a look, and if it takes more than an hour to fix, please revert in the meantime.

(https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Ftryserver.chromium.win%2Fwin_upload_clang%2F186%2F%2B%2Frecipes%2Fsteps%2Fpackage_clang%2F0%2Fstdout)

[hans]

In D33471#763733, @thakis wrote:

Either this or the reland of making allow_user_segv_handler to true broke this test on Windows:

lit.py: E:/b/build/slave/win_upload_clang/build/src/third_party/llvm/tools/clang/test/lit.cfg:200: note: using clang: 'E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.EXE'
-- Testing: 33069 tests, 8 threads --
Testing: 0 .. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90.
FAIL: UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp (31844 of 33069)
******************** TEST 'UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp' FAILED ********************

I'm not sure this is the cause. I rolled back compiler-rt to r303422 and the test still fails for me.

[hans]

In D33471#763825, @hans wrote:

In D33471#763733, @thakis wrote:

Either this or the reland of making allow_user_segv_handler to true broke this test on Windows:

lit.py: E:/b/build/slave/win_upload_clang/build/src/third_party/llvm/tools/clang/test/lit.cfg:200: note: using clang: 'E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.EXE'
-- Testing: 33069 tests, 8 threads --
Testing: 0 .. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90.
FAIL: UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp (31844 of 33069)
******************** TEST 'UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp' FAILED ********************

I'm not sure this is the cause. I rolled back compiler-rt to r303422 and the test still fails for me.

The test started failing with Zach's r303440. With that change, lit interprets the exit value as an error.

I'll see if I can just fix the test.

[hans]

In D33471#763839, @hans wrote:

In D33471#763825, @hans wrote:

In D33471#763733, @thakis wrote:

Either this or the reland of making allow_user_segv_handler to true broke this test on Windows:

lit.py: E:/b/build/slave/win_upload_clang/build/src/third_party/llvm/tools/clang/test/lit.cfg:200: note: using clang: 'E:/b/build/slave/win_upload_clang/build/src/third_party/llvm-bootstrap/./bin/clang.EXE'
-- Testing: 33069 tests, 8 threads --
Testing: 0 .. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90.
FAIL: UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp (31844 of 33069)
******************** TEST 'UBSan-Standalone-x86_64 :: TestCases/Integer/negate-overflow.cpp' FAILED ********************

I'm not sure this is the cause. I rolled back compiler-rt to r303422 and the test still fails for me.

The test started failing with Zach's r303440. With that change, lit interprets the exit value as an error.

I'll see if I can just fix the test.

r303809

lib/asan/asan_win.cc

static long WINAPI SEHHandler(EXCEPTION_POINTERS *info) {
   if (default_seh_handler)
     return default_seh_handler(info);
   return EXCEPTION_CONTINUE_SEARCH;
 }
 
 INTERCEPTOR_WINAPI(LPTOP_LEVEL_EXCEPTION_FILTER, SetUnhandledExceptionFilter,
     LPTOP_LEVEL_EXCEPTION_FILTER ExceptionFilter) {
   CHECK(REAL(SetUnhandledExceptionFilter));
-  if (ExceptionFilter == &SEHHandler || common_flags()->allow_user_segv_handler)
+  if (ExceptionFilter == &SEHHandler)
     return REAL(SetUnhandledExceptionFilter)(ExceptionFilter);
   // We record the user provided exception handler to be called for all the
   // exceptions unhandled by asan.
   Swap(ExceptionFilter, user_seh_handler);
   return ExceptionFilter;
 }
 
 INTERCEPTOR_WINAPI(void, RtlRaiseException, EXCEPTION_RECORD *ExceptionRecord) {