Fix leak of bionic TLS when threads are detached.
__pthread_internal_free doesn't happen on threads that are detached,
causing the bionic TLS allocation (and guard pages) to be leaked.
Fix the leak, and name the allocations to make things apparent if this
ever happens again.
Bug: http://b/36045112
Test: manually ran a program that detached empty threads
Change-Id: Id1c7852b7384474244f7bf5a0f7da54ff962e0a1
diff --git a/libc/bionic/pthread_exit.cpp b/libc/bionic/pthread_exit.cpp
index 3401ed7..9adf405 100644
--- a/libc/bionic/pthread_exit.cpp
+++ b/libc/bionic/pthread_exit.cpp
@@ -92,6 +92,10 @@
thread->alternate_signal_stack = NULL;
}
+ // Unmap the bionic TLS, including guard pages.
+ void* allocation = reinterpret_cast<char*>(thread->bionic_tls) - PAGE_SIZE;
+ munmap(allocation, BIONIC_TLS_SIZE + 2 * PAGE_SIZE);
+
ThreadJoinState old_state = THREAD_NOT_JOINED;
while (old_state == THREAD_NOT_JOINED &&
!atomic_compare_exchange_weak(&thread->join_state, &old_state, THREAD_EXITED_NOT_JOINED)) {