fix: inline data upon overwrites should be readable (#12369)

This PR fixes two bugs

- Remove fi.Data upon overwrite of objects from inlined-data to non-inlined-data
- Workaround for an existing bug on disk with latest releases to ignore fi.Data
  and instead read from the disk for non-inlined-data
- Addtionally add a reserved metadata header to indicate data is inlined for
  a given version.

cmd/erasure-healing.go

@@ -520,6 +520,7 @@ func (er erasureObjects) healObject(ctx context.Context, bucket string, object s
 		if partsMetadata[i].IsRemote() {
 			partsMetadata[i].DataDir = ""
 		}
+
 		// Attempt a rename now from healed data to final location.
 		if err = disk.RenameData(ctx, minioMetaTmpBucket, tmpID, partsMetadata[i], bucket, object); err != nil {
 			logger.LogIf(ctx, err)
@@ -895,7 +896,6 @@ func (er erasureObjects) HealObject(ctx context.Context, bucket, object, version
 
 	// Read metadata files from all the disks
 	partsMetadata, errs := readAllFileInfo(healCtx, storageDisks, bucket, object, versionID, false)
-
 	if isAllNotFound(errs) {
 		err = toObjectErr(errFileNotFound, bucket, object)
 		if versionID != "" {

cmd/erasure-object.go

@@ -214,37 +214,6 @@ func (er erasureObjects) GetObjectNInfo(ctx context.Context, bucket, object stri
 	return fn(pr, h, opts.CheckPrecondFn, pipeCloser, nsUnlocker)
 }
 
-// GetObject - reads an object erasured coded across multiple
-// disks. Supports additional parameters like offset and length
-// which are synonymous with HTTP Range requests.
-//
-// startOffset indicates the starting read location of the object.
-// length indicates the total length of the object.
-func (er erasureObjects) GetObject(ctx context.Context, bucket, object string, startOffset int64, length int64, writer io.Writer, etag string, opts ObjectOptions) (err error) {
-	// Lock the object before reading.
-	lk := er.NewNSLock(bucket, object)
-	lkctx, err := lk.GetRLock(ctx, globalOperationTimeout)
-	if err != nil {
-		return err
-	}
-	ctx = lkctx.Context()
-	defer lk.RUnlock(lkctx.Cancel)
-
-	// Start offset cannot be negative.
-	if startOffset < 0 {
-		logger.LogIf(ctx, errUnexpected, logger.Application)
-		return errUnexpected
-	}
-
-	// Writer cannot be nil.
-	if writer == nil {
-		logger.LogIf(ctx, errUnexpected)
-		return errUnexpected
-	}
-
-	return er.getObject(ctx, bucket, object, startOffset, length, writer, opts)
-}
-
 func (er erasureObjects) getObjectWithFileInfo(ctx context.Context, bucket, object string, startOffset int64, length int64, writer io.Writer, fi FileInfo, metaArr []FileInfo, onlineDisks []StorageAPI) error {
 	// Reorder online disks based on erasure distribution order.
 	// Reorder parts metadata based on erasure distribution order.
@@ -284,6 +253,27 @@ func (er erasureObjects) getObjectWithFileInfo(ctx context.Context, bucket, obje
 	if err != nil {
 		return toObjectErr(err, bucket, object)
 	}
+
+	// This hack is needed to avoid a bug found when overwriting
+	// the inline data object with a un-inlined version, for the
+	// time being we need this as we have released inline-data
+	// version already and this bug is already present in newer
+	// releases.
+	//
+	// This mainly happens with objects < smallFileThreshold when
+	// they are overwritten with un-inlined objects >= smallFileThreshold,
+	// due to a bug in RenameData() the fi.Data is not niled leading to
+	// GetObject thinking that fi.Data is valid while fi.Size has
+	// changed already.
+	if _, ok := fi.Metadata[ReservedMetadataPrefixLower+"inline-data"]; ok {
+		shardFileSize := erasure.ShardFileSize(fi.Size)
+		if shardFileSize >= 0 && shardFileSize >= smallFileThreshold {
+			for i := range metaArr {
+				metaArr[i].Data = nil
+			}
+		}
+	}
+
 	var healOnce sync.Once
 
 	// once we have obtained a common FileInfo i.e latest, we should stick
@@ -373,23 +363,6 @@ func (er erasureObjects) getObjectWithFileInfo(ctx context.Context, bucket, obje
 	return nil
 }
 
-// getObject wrapper for erasure GetObject
-func (er erasureObjects) getObject(ctx context.Context, bucket, object string, startOffset, length int64, writer io.Writer, opts ObjectOptions) error {
-	fi, metaArr, onlineDisks, err := er.getObjectFileInfo(ctx, bucket, object, opts, true)
-	if err != nil {
-		return toObjectErr(err, bucket, object)
-	}
-	if fi.Deleted {
-		if opts.VersionID == "" {
-			return toObjectErr(errFileNotFound, bucket, object)
-		}
-		// Make sure to return object info to provide extra information.
-		return toObjectErr(errMethodNotAllowed, bucket, object)
-	}
-
-	return er.getObjectWithFileInfo(ctx, bucket, object, startOffset, length, writer, fi, metaArr, onlineDisks)
-}
-
 // GetObjectInfo - reads object metadata and replies back ObjectInfo.
 func (er erasureObjects) GetObjectInfo(ctx context.Context, bucket, object string, opts ObjectOptions) (info ObjectInfo, err error) {
 	if !opts.NoLock {
@@ -797,6 +770,13 @@ func (er erasureObjects) putObject(ctx context.Context, bucket string, object st
 		partsMetadata[index].ModTime = modTime
 	}
 
+	if len(inlineBuffers) > 0 {
+		// Set an additional header when data is inlined.
+		for index := range partsMetadata {
+			partsMetadata[index].Metadata[ReservedMetadataPrefixLower+"inline-data"] = "true"
+		}
+	}
+
 	// Rename the successfully written temporary object to final location.
 	if onlineDisks, err = renameData(ctx, onlineDisks, minioMetaTmpBucket, tempObj, partsMetadata, bucket, object, writeQuorum); err != nil {
 		logger.LogIf(ctx, err)

cmd/erasure-object_test.go

@@ -323,9 +323,18 @@ func TestGetObjectNoQuorum(t *testing.T) {
 		}
 	}
 
-	err = xl.GetObject(ctx, bucket, object, 0, int64(len(buf)), ioutil.Discard, "", opts)
-	if err != toObjectErr(errErasureReadQuorum, bucket, object) {
-		t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureReadQuorum, bucket, object), err)
+	gr, err := xl.GetObjectNInfo(ctx, bucket, object, nil, nil, readLock, opts)
+	if err != nil {
+		if err != toObjectErr(errErasureReadQuorum, bucket, object) {
+			t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureReadQuorum, bucket, object), err)
+		}
+	}
+	if gr != nil {
+		_, err = io.Copy(ioutil.Discard, gr)
+		if err != toObjectErr(errErasureReadQuorum, bucket, object) {
+			t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureReadQuorum, bucket, object), err)
+		}
+		gr.Close()
 	}
 
 	// Test use case 2: Make 9 disks offline, which leaves less than quorum number of disks
@@ -359,9 +368,18 @@ func TestGetObjectNoQuorum(t *testing.T) {
 		}
 		z.serverPools[0].erasureDisksMu.Unlock()
 		// Fetch object from store.
-		err = xl.GetObject(ctx, bucket, object, 0, int64(len("abcd")), ioutil.Discard, "", opts)
-		if err != toObjectErr(errErasureReadQuorum, bucket, object) {
-			t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureWriteQuorum, bucket, object), err)
+		gr, err := xl.GetObjectNInfo(ctx, bucket, object, nil, nil, readLock, opts)
+		if err != nil {
+			if err != toObjectErr(errErasureReadQuorum, bucket, object) {
+				t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureReadQuorum, bucket, object), err)
+			}
+		}
+		if gr != nil {
+			_, err = io.Copy(ioutil.Discard, gr)
+			if err != toObjectErr(errErasureReadQuorum, bucket, object) {
+				t.Errorf("Expected GetObject to fail with %v, but failed with %v", toObjectErr(errErasureReadQuorum, bucket, object), err)
+			}
+			gr.Close()
 		}
 	}
 

cmd/storage-rest-common.go

@@ -18,7 +18,7 @@
 package cmd
 
 const (
-	storageRESTVersion       = "v34" // Streaming Usage Updates
+	storageRESTVersion       = "v35" // Inline bugfix needs all servers to be updated
 	storageRESTVersionPrefix = SlashSeparator + storageRESTVersion
 	storageRESTPrefix        = minioReservedBucketPath + "/storage"
 )

cmd/xl-storage.go

@@ -1076,6 +1076,11 @@ func (s *xlStorage) ReadVersion(ctx context.Context, volume, path, versionID str
 
 	if readData {
 		if len(fi.Data) > 0 || fi.Size == 0 {
+			if len(fi.Data) > 0 {
+				if _, ok := fi.Metadata[ReservedMetadataPrefixLower+"inline-data"]; !ok {
+					fi.Metadata[ReservedMetadataPrefixLower+"inline-data"] = "true"
+				}
+			}
 			return fi, nil
 		}
 
@@ -2023,6 +2028,7 @@ func (s *xlStorage) RenameData(ctx context.Context, srcVolume, srcPath string, f
 				// Purge the destination path as we are not preserving anything
 				// versioned object was not requested.
 				oldDstDataPath = pathJoin(dstVolumeDir, dstPath, ofi.DataDir)
+				xlMeta.data.remove(nullVersionID, ofi.DataDir)
 			}
 		}
 	}