dm ioctl: prevent rename to empty name or uuid

[firefly-linux-kernel-4.4.55.git] / drivers / md / dm-ioctl.c

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index f1b758675ec77e2e2c0d16246e2ba772fff01476..5667cea55e719a94870ddc31a87372a4e1d20017 100644 (file)
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -877,7 +877,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
        unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
 
        if (new_data < param->data ||
-           invalid_str(new_data, (void *) param + param_size) ||
+           invalid_str(new_data, (void *) param + param_size) || !*new_data ||
            strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
                DMWARN("Invalid new mapped device name or uuid string supplied.");
                return -EINVAL;