diff --git a/core/src/services/sftp/backend.rs b/core/src/services/sftp/backend.rs
index d6ec3c08041..8e3c103f786 100644
--- a/core/src/services/sftp/backend.rs
+++ b/core/src/services/sftp/backend.rs
@@ -396,8 +396,6 @@ impl Access for SftpBackend {
             .await
             .map_err(parse_sftp_error)?;
 
-        let meta = f.metadata().await.map_err(parse_sftp_error)?;
-
         if args.range().offset() != 0 {
             f.seek(SeekFrom::Start(args.range().offset()))
                 .await
@@ -406,7 +404,7 @@ impl Access for SftpBackend {
 
         Ok((
             RpRead::default(),
-            SftpReader::new(client, f, args.range().size().and(meta.len())),
+            SftpReader::new(client, f, args.range().size()),
         ))
     }
 
diff --git a/core/src/services/sftp/reader.rs b/core/src/services/sftp/reader.rs
index 6b4ceeff1cc..936e315acd1 100644
--- a/core/src/services/sftp/reader.rs
+++ b/core/src/services/sftp/reader.rs
@@ -50,7 +50,7 @@ impl SftpReader {
 
 impl oio::Read for SftpReader {
     async fn read(&mut self) -> Result<Buffer> {
-        if Some(self.read) >= self.size {
+        if self.read >= self.size.unwrap_or(usize::MAX) {
             return Ok(Buffer::new());
         }
 
@@ -71,6 +71,8 @@ impl oio::Read for SftpReader {
         };
 
         self.read += bytes.len();
-        Ok(Buffer::from(bytes.freeze()))
+        self.buf = bytes;
+        let bs = self.buf.split();
+        Ok(Buffer::from(bs.freeze()))
     }
 }