Fix pthread_detach for already-exited threads.
Change-Id: I2bf7f41234d93b226132a4c51705f4186f4961c3
Reported-by: Paresh Nakhe <pnakhe@codeaurora.org>
diff --git a/libc/bionic/pthread_detach.cpp b/libc/bionic/pthread_detach.cpp
index 95f11ac..a8608e3 100644
--- a/libc/bionic/pthread_detach.cpp
+++ b/libc/bionic/pthread_detach.cpp
@@ -44,6 +44,12 @@
return 0; // Already being joined; silently do nothing, like glibc.
}
+ if (thread->tid == 0) {
+ // Already exited; clean up.
+ _pthread_internal_remove_locked(thread.get());
+ return 0;
+ }
+
thread->attr.flags |= PTHREAD_ATTR_FLAG_DETACHED;
return 0;
}
diff --git a/tests/pthread_test.cpp b/tests/pthread_test.cpp
index 1e85a54..9e7a9bc 100644
--- a/tests/pthread_test.cpp
+++ b/tests/pthread_test.cpp
@@ -19,6 +19,7 @@
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
+#include <malloc.h>
#include <pthread.h>
#include <signal.h>
#include <sys/mman.h>
@@ -350,6 +351,35 @@
ASSERT_EQ(ESRCH, pthread_detach(dead_thread));
}
+TEST(pthread, pthread_detach__leak) {
+ size_t initial_bytes = mallinfo().uordblks;
+
+ pthread_attr_t attr;
+ ASSERT_EQ(0, pthread_attr_init(&attr));
+ ASSERT_EQ(0, pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE));
+
+ std::vector<pthread_t> threads;
+ for (size_t i = 0; i < 32; ++i) {
+ pthread_t t;
+ ASSERT_EQ(0, pthread_create(&t, &attr, IdFn, NULL));
+ threads.push_back(t);
+ }
+
+ sleep(1);
+
+ for (size_t i = 0; i < 32; ++i) {
+ ASSERT_EQ(0, pthread_detach(threads[i])) << i;
+ }
+
+ size_t final_bytes = mallinfo().uordblks;
+
+ int leaked_bytes = (final_bytes - initial_bytes);
+
+ // User code (like this test) doesn't know how large pthread_internal_t is.
+ // We can be pretty sure it's more than 128 bytes.
+ ASSERT_LT(leaked_bytes, 32 /*threads*/ * 128 /*bytes*/);
+}
+
TEST(pthread, pthread_getcpuclockid__clock_gettime) {
pthread_t t;
ASSERT_EQ(0, pthread_create(&t, NULL, SleepFn, reinterpret_cast<void*>(5)));