1 files changed, 96 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/tst-clone3.c b/sysdeps/unix/sysv/linux/tst-clone3.c
new file mode 100644
index 0000000000..a742237cb3
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-clone3.c
@@ -0,0 +1,96 @@
+/* Check if clone (CLONE_THREAD) does not call exit_group (BZ #21512)
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <sched.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <linux/futex.h>
+
+#include <stackinfo.h>  /* For _STACK_GROWS_{UP,DOWN}.  */
+#include <support/check.h>
+
+/* Test if clone call with CLONE_THREAD does not call exit_group.  The 'f'
+   function returns '1', which will be used by clone thread to call the
+   'exit' syscall directly.  If _exit is used instead, exit_group will be
+   used and thus the thread group will finish with return value of '1'
+   (where '2' from main thread is expected.  */
+
+static int
+f (void *a)
+{
+  return 1;
+}
+
+/* Futex wait for TID argument, similar to pthread_join internal
+   implementation.  */
+#define wait_tid(tid) \
+  do {					\
+    __typeof (tid) __tid;		\
+    while ((__tid = (tid)) != 0)	\
+      futex_wait (&(tid), __tid);	\
+  } while (0)
+
+static inline int
+futex_wait (int *futexp, int val)
+{
+  return syscall (__NR_futex, futexp, FUTEX_WAIT, val);
+}
+
+static int
+do_test (void)
+{
+  char st[1024] __attribute__ ((aligned));
+  int clone_flags = CLONE_THREAD;
+  /* Minimum required flags to used along with CLONE_THREAD.  */
+  clone_flags |= CLONE_VM | CLONE_SIGHAND;
+  /* We will used ctid to call on futex to wait for thread exit.  */
+  clone_flags |= CLONE_CHILD_CLEARTID;
+  pid_t ctid, tid;
+
+#ifdef __ia64__
+  extern int __clone2 (int (*__fn) (void *__arg), void *__child_stack_base,
+		       size_t __child_stack_size, int __flags,
+		       void *__arg, ...);
+  tid = __clone2 (f, st, sizeof (st), clone_flags, NULL, /* ptid */ NULL,
+		  /* tls */ NULL, &ctid);
+#else
+#if _STACK_GROWS_DOWN
+  tid = clone (f, st + sizeof (st), clone_flags, NULL, /* ptid */ NULL,
+	       /* tls */ NULL, &ctid);
+#elif _STACK_GROWS_UP
+  tid = clone (f, st, clone_flags, NULL, /* ptid */ NULL, /* tls */ NULL,
+	       &ctid);
+#else
+#error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
+#endif
+#endif
+  if (tid == -1)
+    FAIL_EXIT1 ("clone failed: %m");
+
+  ctid = tid;
+  wait_tid (ctid);
+
+  return 2;
+}
+
+#define EXPECTED_STATUS 2
+#include <support/test-driver.c>