--- /dev/null
+From ebiggers3@gmail.com Mon Feb 26 20:36:21 2018
+From: Eric Biggers <ebiggers3@gmail.com>
+Date: Mon, 26 Feb 2018 10:56:45 -0800
+Subject: binder: add missing binder_unlock()
+To: stable@vger.kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Guenter Roeck <linux@roeck-us.net>, Todd Kjos <tkjos@android.com>, Eric Biggers <ebiggers@google.com>
+Message-ID: <20180226185645.241652-1-ebiggers3@gmail.com>
+
+
+From: Eric Biggers <ebiggers@google.com>
+
+When commit 4be5a2810489 ("binder: check for binder_thread allocation
+failure in binder_poll()") was applied to 4.4-stable and 4.9-stable it
+was forgotten to release the global binder lock in the new error path.
+The global binder lock wasn't removed until v4.14, by commit
+a60b890f607d ("binder: remove global binder lock").
+
+Fix the new error path to release the lock.
+
+Reported-by: Guenter Roeck <linux@roeck-us.net>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/android/binder.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/android/binder.c
++++ b/drivers/android/binder.c
+@@ -2628,8 +2628,10 @@ static unsigned int binder_poll(struct f
+ binder_lock(__func__);
+
+ thread = binder_get_thread(proc);
+- if (!thread)
++ if (!thread) {
++ binder_unlock(__func__);
+ return POLLERR;
++ }
+
+ wait_for_proc_work = thread->transaction_stack == NULL &&
+ list_empty(&thread->todo) && thread->return_error == BR_OK;