diff --git a/common/bufio/cache.go b/common/bufio/cache.go
index e1eda0a..ace7259 100644
--- a/common/bufio/cache.go
+++ b/common/bufio/cache.go
@@ -3,7 +3,6 @@ package bufio
 import (
 	"io"
 	"net"
-	"time"
 
 	"github.com/sagernet/sing/common/buf"
 	M "github.com/sagernet/sing/common/metadata"
@@ -60,13 +59,6 @@ func (c *CachedConn) WriteTo(w io.Writer) (n int64, err error) {
 	return
 }
 
-func (c *CachedConn) SetReadDeadline(t time.Time) error {
-	if c.buffer != nil && !c.buffer.IsEmpty() {
-		return nil
-	}
-	return c.Conn.SetReadDeadline(t)
-}
-
 func (c *CachedConn) ReadFrom(r io.Reader) (n int64, err error) {
 	return Copy(c.Conn, r)
 }