diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 0bbccac94d6c..6f8b67e61771 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1062,6 +1062,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 			req->num_sgs = io_data->sgt.nents;
 		} else {
 			req->buf = data;
+			req->num_sgs = 0;
 		}
 		req->length = data_len;
 
@@ -1105,6 +1106,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 			req->num_sgs = io_data->sgt.nents;
 		} else {
 			req->buf = data;
+			req->num_sgs = 0;
 		}
 		req->length = data_len;