Merge tag 'staging-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fix from Greg KH:
 "Here is a single android ashmem bugfix that resolves a reported issue
  in that interface. It's been in linux-next this week with no reported
  issues"

* tag 'staging-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl
diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
index 0f695df..372ce99 100644
--- a/drivers/staging/android/ashmem.c
+++ b/drivers/staging/android/ashmem.c
@@ -765,10 +765,12 @@ static long ashmem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		break;
 	case ASHMEM_SET_SIZE:
 		ret = -EINVAL;
+		mutex_lock(&ashmem_mutex);
 		if (!asma->file) {
 			ret = 0;
 			asma->size = (size_t)arg;
 		}
+		mutex_unlock(&ashmem_mutex);
 		break;
 	case ASHMEM_GET_SIZE:
 		ret = asma->size;