diff --git a/pkg/rclonefs/base.go b/pkg/rclonefs/base.go
index 00b51af7..6713d9d5 100644
--- a/pkg/rclonefs/base.go
+++ b/pkg/rclonefs/base.go
@@ -84,7 +84,8 @@ func (r *BaseRcloneDisk) PutMultipart(
 
 	fileHeader := make([]byte, 512)
 
-	if _, err := f.Read(fileHeader); err != nil {
+	n, err := io.ReadFull(f, fileHeader)
+	if err != nil && !errors.Is(err, io.ErrUnexpectedEOF) && !errors.Is(err, io.EOF) {
 		return nil, err
 	}
 
@@ -93,7 +94,7 @@ func (r *BaseRcloneDisk) PutMultipart(
 	}
 
 	dst := ""
-	fileType := http.DetectContentType(fileHeader)
+	fileType := http.DetectContentType(fileHeader[:n])
 
 	if !r.IsAllowedMime(strings.ToLower(fileType)) {
 		return nil, errors.New("file type is not allowed")
diff --git a/pkg/restfulresolver/context.go b/pkg/restfulresolver/context.go
index b205bf8a..f2a731fc 100644
--- a/pkg/restfulresolver/context.go
+++ b/pkg/restfulresolver/context.go
@@ -1,7 +1,9 @@
 package restfulresolver
 
 import (
+	"errors"
 	"fmt"
+	"io"
 	"net/http"
 	"strconv"
 	"strings"
@@ -282,7 +284,8 @@ func (c *Context) Files() ([]*fs.File, error) {
 
 			m := make([]byte, 512)
 
-			if _, err := f.Read(m); err != nil {
+			n, err := io.ReadFull(f, m)
+			if err != nil && !errors.Is(err, io.ErrUnexpectedEOF) && !errors.Is(err, io.EOF) {
 				return nil, err
 			}
 
@@ -293,7 +296,7 @@ func (c *Context) Files() ([]*fs.File, error) {
 			files = append(files, &fs.File{
 				Name:   fileHeader.Filename,
 				Size:   uint64(fileHeader.Size),
-				Type:   http.DetectContentType(m),
+				Type:   http.DetectContentType(m[:n]),
 				Reader: f,
 			})
 		}