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[inspector][fuzzer] Fix termination

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Joining the thread from the watchdog is problematic, since e.g.
{pthread_join} (the implementation of {Thread::Join} on POSIX systems)
has undefined behaviour if multiple threads try to join at the same
time. In practice, this leads to deadlocks.

Thus implement termination by just calling {TaskRunner::Terminate}, but
not {TaskRunner::Join}. This fixes the deadlocks in the inspector
fuzzer.
The inspector test binary is fixed simarly, even though there it seems
to not cause problems so far.

In both files, the {Terminate} function is inlined into callers because
it's only a single line now, with one to two users.

Also, replace the single fuzzer test (which is invalid javascript) by
two tests: One called "invalid" explicitly, still with invalid
javascript, and one empty file, which is valid input. That one
reproduced the deadlock.

R=szuend@chromium.org

Bug: chromium:1142437
Change-Id: I8fb98b0cdbf3ceff6af6849397e5da5a4e9acd3c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2526384
Reviewed-by: Simon Zünd <szuend@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71054}
This commit is contained in:
Clemens Backes 2020-11-09 14:37:17 +01:00 committed by Commit Bot
parent c9e883e803
commit 4510401df4
5 changed files with 8 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
test/fuzzer/inspector-fuzzer.cc
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@ -32,13 +32,6 @@ namespace {
base::SmallVector<TaskRunner*, 2> task_runners;
void Terminate() {
for (TaskRunner* r : task_runners) {
r->Terminate();
r->Join();
}
}
class UtilsExtension : public IsolateData::SetupGlobalTask {
public:
~UtilsExtension() override = default;
@ -88,7 +81,9 @@ class UtilsExtension : public IsolateData::SetupGlobalTask {
static TaskRunner* backend_runner_;
static void Quit(const v8::FunctionCallbackInfo<v8::Value>& args) {
Terminate();
// Only terminate, so not join the threads here, since joining concurrently
// from multiple threads can be undefined behaviour (see pthread_join).
for (TaskRunner* task_runner : task_runners) task_runner->Terminate();
}
static void CompileAndRunWithOrigin(
@ -561,7 +556,7 @@ class Watchdog final : public base::Thread {
private:
void Run() override {
if (semaphore_->WaitFor(kMaxExecutionSeconds)) return;
Terminate();
for (TaskRunner* task_runner : task_runners) task_runner->Terminate();
}
base::Semaphore* const semaphore_;

0
test/fuzzer/inspector/empty Normal file
View File

1
test/fuzzer/inspector/foo
View File

@ -1 +0,0 @@
smoke test

1
test/fuzzer/inspector/invalid Normal file
View File

@ -0,0 +1 @@
no valid javascript

11
test/inspector/inspector-test.cc
View File

@ -41,13 +41,6 @@ namespace {
base::SmallVector<TaskRunner*, 2> task_runners;
void Terminate() {
for (TaskRunner* task_runner : task_runners) {
task_runner->Terminate();
task_runner->Join();
}
}
class UtilsExtension : public IsolateData::SetupGlobalTask {
public:
~UtilsExtension() override = default;
@ -154,7 +147,9 @@ class UtilsExtension : public IsolateData::SetupGlobalTask {
static void Quit(const v8::FunctionCallbackInfo<v8::Value>& args) {
fflush(stdout);
fflush(stderr);
Terminate();
// Only terminate, so not join the threads here, since joining concurrently
// from multiple threads can be undefined behaviour (see pthread_join).
for (TaskRunner* task_runner : task_runners) task_runner->Terminate();
}
static void Setlocale(const v8::FunctionCallbackInfo<v8::Value>& args) {