diff --git a/drivers/scsi/ufs/ufs-qcom-debugfs.c b/drivers/scsi/ufs/ufs-qcom-debugfs.c
index 494ecd1c5f79..db4ecec6cf2f 100644
--- a/drivers/scsi/ufs/ufs-qcom-debugfs.c
+++ b/drivers/scsi/ufs/ufs-qcom-debugfs.c
@@ -121,7 +121,8 @@ static ssize_t ufs_qcom_dbg_testbus_cfg_write(struct file *file,
 	struct ufs_hba *hba = host->hba;
 
 
-	ret = simple_write_to_buffer(configuration, TESTBUS_CFG_BUFF_LINE_SIZE,
+	ret = simple_write_to_buffer(configuration,
+		TESTBUS_CFG_BUFF_LINE_SIZE - 1,
 		&buff_pos, ubuf, cnt);
 	if (ret < 0) {
 		dev_err(host->hba->dev, "%s: failed to read user data\n",