fix: Resolves the null object version get issue from posix directory

backend/posix/posix.go

@@ -2717,8 +2717,7 @@ func (p *Posix) GetObject(_ context.Context, input *s3.GetObjectInput) (*s3.GetO
 			return nil, fmt.Errorf("get obj versionId: %w", err)
 		}
 		if errors.Is(err, meta.ErrNoSuchKey) {
-			bucket = filepath.Join(p.versioningDir, bucket)
-			object = filepath.Join(genObjVersionKey(object), versionId)
+			vId = []byte(nullVersionId)
 		}
 
 		if string(vId) != versionId {

tests/integration/group-tests.go

@@ -564,6 +564,7 @@ func TestVersioning(s *S3Conf) {
 	Versioning_GetObject_success(s)
 	Versioning_GetObject_delete_marker_without_versionId(s)
 	Versioning_GetObject_delete_marker(s)
+	Versioning_GetObject_null_versionId_obj(s)
 	// DeleteObject(s) actions
 	Versioning_DeleteObject_delete_object_version(s)
 	Versioning_DeleteObject_non_existing_object(s)
@@ -949,6 +950,7 @@ func GetIntTests() IntTests {
 		"Versioning_GetObject_success":                                        Versioning_GetObject_success,
 		"Versioning_GetObject_delete_marker_without_versionId":                Versioning_GetObject_delete_marker_without_versionId,
 		"Versioning_GetObject_delete_marker":                                  Versioning_GetObject_delete_marker,
+		"Versioning_GetObject_null_versionId_obj":                             Versioning_GetObject_null_versionId_obj,
 		"Versioning_DeleteObject_delete_object_version":                       Versioning_DeleteObject_delete_object_version,
 		"Versioning_DeleteObject_non_existing_object":                         Versioning_DeleteObject_non_existing_object,
 		"Versioning_DeleteObject_delete_a_delete_marker":                      Versioning_DeleteObject_delete_a_delete_marker,

tests/integration/tests.go

@@ -11455,6 +11455,48 @@ func Versioning_GetObject_delete_marker(s *S3Conf) error {
 	}, withVersioning(types.BucketVersioningStatusEnabled))
 }
 
+func Versioning_GetObject_null_versionId_obj(s *S3Conf) error {
+	testName := "Versioning_GetObject_null_versionId_obj"
+	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {
+		obj, lgth := "my-obj", int64(234)
+		out, err := putObjectWithData(lgth, &s3.PutObjectInput{
+			Bucket: &bucket,
+			Key:    &obj,
+		}, s3client)
+		if err != nil {
+			return err
+		}
+
+		err = putBucketVersioningStatus(s3client, bucket, types.BucketVersioningStatusEnabled)
+		if err != nil {
+			return err
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), shortTimeout)
+		res, err := s3client.GetObject(ctx, &s3.GetObjectInput{
+			Bucket:    &bucket,
+			Key:       &obj,
+			VersionId: &nullVersionId,
+		})
+		cancel()
+		if err != nil {
+			return err
+		}
+
+		if *res.ContentLength != lgth {
+			return fmt.Errorf("expected the Content-Length to be %v, instead got %v", lgth, *res.ContentLength)
+		}
+		if *res.VersionId != nullVersionId {
+			return fmt.Errorf("expected the versionId to be %v, insted got %v", nullVersionId, *res.VersionId)
+		}
+		if *res.ETag != *out.res.ETag {
+			return fmt.Errorf("expecte the ETag to be %v, instead got %v", *out.res.ETag, *res.ETag)
+		}
+
+		return nil
+	})
+}
+
 func Versioning_DeleteObject_delete_object_version(s *S3Conf) error {
 	testName := "Versioning_DeleteObject_delete_object_version"
 	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {