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

drivers/staging/android/ashmem.c

···
 		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;