[compiler-rt][rtsan] pthread_detach/pthread_kill interception.

[devnexen]

No description provided.

[llvmbot]

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: David CARLIER (devnexen)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/126765.diff

2 Files Affected:

• (modified) compiler-rt/lib/rtsan/rtsan_interceptors_posix.cpp (+12)
• (modified) compiler-rt/lib/rtsan/tests/rtsan_test_interceptors_posix.cpp (+22)

diff --git a/compiler-rt/lib/rtsan/rtsan_interceptors_posix.cpp b/compiler-rt/lib/rtsan/rtsan_interceptors_posix.cpp
index 410da0748b433..af074d119e86a 100644
--- a/compiler-rt/lib/rtsan/rtsan_interceptors_posix.cpp
+++ b/compiler-rt/lib/rtsan/rtsan_interceptors_posix.cpp
@@ -749,6 +749,16 @@ INTERCEPTOR(int, pthread_rwlock_wrlock, pthread_rwlock_t *lock) {
   return REAL(pthread_rwlock_wrlock)(lock);
 }
 
+INTERCEPTOR(int, pthread_detach, pthread_t thread) {
+  __rtsan_notify_intercepted_call("pthread_detach");
+  return REAL(pthread_detach)(thread);
+}
+
+INTERCEPTOR(int, pthread_kill, pthread_t thread, int signal) {
+  __rtsan_notify_intercepted_call("pthread_kill");
+  return REAL(pthread_kill)(thread, signal);
+}
+
 // Sleeping
 
 INTERCEPTOR(unsigned int, sleep, unsigned int s) {
@@ -1498,6 +1508,8 @@ void __rtsan::InitializeInterceptors() {
   INTERCEPT_FUNCTION(pthread_rwlock_rdlock);
   INTERCEPT_FUNCTION(pthread_rwlock_unlock);
   INTERCEPT_FUNCTION(pthread_rwlock_wrlock);
+  INTERCEPT_FUNCTION(pthread_detach);
+  INTERCEPT_FUNCTION(pthread_kill);
 
   INTERCEPT_FUNCTION(sleep);
   INTERCEPT_FUNCTION(usleep);
diff --git a/compiler-rt/lib/rtsan/tests/rtsan_test_interceptors_posix.cpp b/compiler-rt/lib/rtsan/tests/rtsan_test_interceptors_posix.cpp
index 98d27caae94b8..994aeff6a1c8c 100644
--- a/compiler-rt/lib/rtsan/tests/rtsan_test_interceptors_posix.cpp
+++ b/compiler-rt/lib/rtsan/tests/rtsan_test_interceptors_posix.cpp
@@ -1148,6 +1148,28 @@ TEST(TestRtsanInterceptors, PthreadCondWaitDiesWhenRealtime) {
   pthread_mutex_destroy(&mutex);
 }
 
+TEST(TestRtsanInterceptors, PthreadDetachDiesWhenRealtime) {
+  pthread_t thread{};
+  ASSERT_EQ(0,
+            pthread_create(&thread, nullptr, &FakeThreadEntryPoint, nullptr));
+
+  auto Func = [&thread]() { pthread_detach(thread); };
+
+  ExpectRealtimeDeath(Func, "pthread_detach");
+  ExpectNonRealtimeSurvival(Func);
+}
+
+TEST(TestRtsanInterceptors, PthreadKillDiesWhenRealtime) {
+  pthread_t thread{};
+  ASSERT_EQ(0,
+            pthread_create(&thread, nullptr, &FakeThreadEntryPoint, nullptr));
+
+  auto Func = [&thread]() { pthread_kill(thread, -1); };
+
+  ExpectRealtimeDeath(Func, "pthread_kill");
+  ExpectNonRealtimeSurvival(Func);
+}
+
 class PthreadRwlockTest : public ::testing::Test {
 protected:
   void SetUp() override {

[davidtrevelyan]

@devnexen thanks for the suggestion - how confident are you that both pthread_detach and pthread_kill are blocking? Have you taken a look at any implementations of these already? If they tend to just flick small atomic switches and return instantly, I'd be wary of including these interceptors.

[devnexen]

Ah I did not look at linux/glibc, maybe we should add it only for freebsd later down the line.

[davidtrevelyan]

Ah I did not look at linux/glibc, maybe we should add it only for freebsd later down the line.

Sorry - please could you clarify what you're proposing here? Do you mean introduce it for FreeBSD now and Linux later, or Linux now and FreeBSD later?

[devnexen]

I would say not Linux but FreeBSD later.

[davidtrevelyan]

@devnexen OK - are you happy if we close this PR for now?

[devnexen]

Sure I mean either that or rebasing later whatever you all prefer.