http2 throws custom error Content-Length shorter handle it

We should internally handle when http2 input stream has smaller
content than its content-length header

Upstream issue reported golang/go#30648

This a change which we need to handle internally until Go fixes it
correctly, till now our code doesn't expect a custom error to be returned.

Author: harshavardhana

cmd/fs-v1-multipart.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	pathutil "path"
@@ -304,6 +305,10 @@ func (fs *FSObjects) PutObjectPart(ctx context.Context, bucket, object, uploadID
 	tmpPartPath := pathJoin(fs.fsPath, minioMetaTmpBucket, fs.fsUUID, uploadID+"."+mustGetUUID()+"."+strconv.Itoa(partID))
 	bytesWritten, err := fsCreateFile(ctx, tmpPartPath, data, buf, data.Size())
 	if err != nil {
+		if bytesWritten > 0 && bytesWritten < data.Size() {
+			err = io.ErrUnexpectedEOF
+		}
+
 		fsRemoveFile(ctx, tmpPartPath)
 		return pi, toObjectErr(err, minioMetaTmpBucket, tmpPartPath)
 	}

cmd/fs-v1.go

@@ -905,6 +905,10 @@ func (fs *FSObjects) putObject(ctx context.Context, bucket string, object string
 	fsTmpObjPath := pathJoin(fs.fsPath, minioMetaTmpBucket, fs.fsUUID, tempObj)
 	bytesWritten, err := fsCreateFile(ctx, fsTmpObjPath, data, buf, data.Size())
 	if err != nil {
+		if bytesWritten > 0 && bytesWritten < data.Size() {
+			err = io.ErrUnexpectedEOF
+		}
+
 		fsRemoveFile(ctx, fsTmpObjPath)
 		return ObjectInfo{}, toObjectErr(err, bucket, object)
 	}

cmd/posix.go

@@ -1091,16 +1091,13 @@ func (s *posix) CreateFile(volume, path string, fileSize int64, r io.Reader) (er
 	defer s.pool.Put(bufp)
 
 	n, err := io.CopyBuffer(w, r, *bufp)
-	if err != nil {
-		return err
-	}
 	if n < fileSize {
 		return errLessData
 	}
 	if n > fileSize {
 		return errMoreData
 	}
-	return nil
+	return err
 }
 
 func (s *posix) WriteAll(volume, path string, buf []byte) (err error) {