Allow sanitizer coverage to create *.sancov files when sandboxed

Allow sanitizer coverage to create *.sancov files when sandboxed

Due to sandbox restrictions and for the sake of code simplicity, we have
to specify the directory in two environment variables:
SANITIZER_COVERAGE_DIR=XXX
and
ASAN_OPTIONS=coverage=1:coverage_dir="XXX"

This CL supercedes https://codereview.chromium.org/1113013003/

R=timurrrr@chromium.org,cpu@chromium.org
BUG=430156
Committed: https://crrev.com/e172214f4e0769bf82fb678930dd6e55009ff926
Cr-Commit-Position: refs/heads/master@{#329517}

[Reid Kleckner, 2015-05-12 00:35:29]

Timur, how can I build and test this configuration? I tried doing this and it
failed to build with ASan CHECK failures:

set GYP_GENERATOR_FLAGS=output_dir=out_asan
set GYP_DEFINES=component=static_library clang=1 make_clang_dir=../../llvm/build
asan=1 sanitizer_coverage=1 disable_nacl=1 test_isolation=noop
gclient runhooks
ninja -C out_asan\Release obj\content\common\content_common.sandbox_win.obj
... builds for a while ...
[713/5026] RULE yasm genperf for
source\patched-yasm\modules\arch\x86\x86cpu.gperf
FAILED: D:\src\depot_tools\python276_bin\python.exe gyp-win-tool action-wrapper
environment.x86
generate_files_target_generate_gperf_fee94f7739c629e85672d8193d185c4e.411c0ae709ab15d2bc9550dbff41f5cd.rsp
..\..\third_party\yasm
==26372==WARNING: AddressSanitizer failed to mprotect 0x00010000 (65536) bytes
at 0x14d70000 (error code: 487)
==26372==ERROR: AddressSanitizer failed to deallocate 0x0 (0) bytes at address
0x00000000 (error code: 487)
==26372==AddressSanitizer CHECK failed:
..\projects\compiler-rt\lib\sanitizer_common\sanitizer_win.cc:100 "(("unable to
unmap" && 0)) != (0)" (0x0, 0x0)
    #0 0x89f8d7 in __asan::AsanCheckFailed
d:\src\llvm\projects\compiler-rt\lib\asan\asan_rtl.cc:69
    #1 0x8a7b04 in __sanitizer::CheckFailed
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_common.cc:130
    #2 0x8a9d74 in __sanitizer::UnmapOrDie
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_win.cc:100
    #3 0x8a2e9c in
__sanitizer::InternalMmapVectorNoCtor<__asan::GlobalRegistrationSite>::Resize
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_common.h:464
    #4 0x8a30ed in
__sanitizer::InternalMmapVectorNoCtor<__asan::GlobalRegistrationSite>::push_back
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_common.h:430
    #5 0x89ec3d in __sanitizer::CoverageData::InitializeGuards
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_coverage_libcdep.cc:350
    #6 0x89f72b in __sanitizer_cov_module_init
d:\src\llvm\projects\compiler-rt\lib\sanitizer_common\sanitizer_coverage_libcdep.cc:835
    #7 0x895886 in report_error+0x1a6
(D:\src\chromium\src\out_asan\Release\genperf.exe+0x5886)
    #8 0x8b929f in _cinit f:\dd\vctools\crt\crtw32\startup\crt0dat.c:308
    #9 0x8bad10 in __tmainCRTStartup f:\dd\vctools\crt\crtw32\startup\crt0.c:237
    #10 0x768c3369 in BaseThreadInitThunk+0x11
(C:\Windows\syswow64\kernel32.dll+0x13369)
    #11 0x774292b1 in RtlInitializeExceptionChain+0x62
(C:\Windows\SysWOW64\ntdll.dll+0x392b1)
    #12 0x77429284 in RtlInitializeExceptionChain+0x35
(C:\Windows\SysWOW64\ntdll.dll+0x39284)

[cpu_(ooo_6.6-7.5), 2015-05-12 00:53:56]

https://codereview.chromium.org/1140653002/diff/1/content/common/sandbox_win.cc
File content/common/sandbox_win.cc (right):

https://codereview.chromium.org/1140653002/diff/1/content/common/sandbox_win....
content/common/sandbox_win.cc:370: L"SANITIZER_COVERAGE_DIR",
coverage_dir.data(), coverage_dir_size);
lgtm, please use base's  WriteInto() instead of 368 + 376 and for the record
trying to fend off SANITIZER_COVERAGE_DIR size change between the two calls is
not worth it, but if you really really want it you can have it.

[Reid Kleckner, 2015-05-12 16:03:07]

I still haven't been able to build the code I'm changing because it's under that
ifdef, and I'm struggling with the asan build.

https://codereview.chromium.org/1140653002/diff/1/content/common/sandbox_win.cc
File content/common/sandbox_win.cc (right):

https://codereview.chromium.org/1140653002/diff/1/content/common/sandbox_win....
content/common/sandbox_win.cc:370: L"SANITIZER_COVERAGE_DIR",
coverage_dir.data(), coverage_dir_size);
On 2015/05/12 00:53:56, cpu wrote:
> lgtm, please use base's  WriteInto() instead of 368 + 376 and for the record
> trying to fend off SANITIZER_COVERAGE_DIR size change between the two calls is
> not worth it, but if you really really want it you can have it.

Sure. I felt like the CHECK was calling out the assumption that nobody is racing
in and changing this env var while Chrome is running.

[Reid Kleckner, 2015-05-12 16:59:48]

Use WriteInto

[Reid Kleckner, 2015-05-12 21:25:56]

Took me a while, but I finally managed to test this manually and verified that
the sancov files got created when I set this env var. Thanks for the review,
landing away!

[Reid Kleckner, 2015-05-12 21:26:01]

The CQ bit was checked by rnk@chromium.org

[Reid Kleckner, 2015-05-12 21:26:01]

The patchset sent to the CQ was uploaded after l-g-t-m from cpu@chromium.org
Link to the patchset: https://codereview.chromium.org/1140653002/#ps20001
(title: "Use WriteInto")

[commit-bot: I haz the power, 2015-05-12 21:27:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1140653002/20001

[commit-bot: I haz the power, 2015-05-12 22:29:57]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-05-12 22:31:19]

Patchset 2 (id:??) landed as
https://crrev.com/e172214f4e0769bf82fb678930dd6e55009ff926
Cr-Commit-Position: refs/heads/master@{#329517}