staging: usbip: userspace: Check return value for mkdir()

mkdir() could fail, so we should check its return value.

Signed-off-by: Tobias Klauser <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/usbip/userspace/src/usbip_attach.c

···
 	char buff[MAX_BUFF+1];
 	int ret;
 
-	mkdir(VHCI_STATE_PATH, 0700);
+	ret = mkdir(VHCI_STATE_PATH, 0700);
+	if (ret < 0)
+		return -1;
 
 	snprintf(path, PATH_MAX, VHCI_STATE_PATH"/port%d", rhport);