From 684cb13c54b99f1ee2e500d58732cca177912c61 Mon Sep 17 00:00:00 2001
From: Madhu Rajanna <madhupr007@gmail.com>
Date: Thu, 16 Jul 2020 15:28:27 +0530
Subject: [PATCH] rbd: DisAllow CreateVoulume for missmatch volume size

If the requested volume size and the snapshot or the
parent volume from which the clone is to be created
is not equal cephcsi returns an error message.

updates #1188

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
---
 internal/rbd/controllerserver.go | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/internal/rbd/controllerserver.go b/internal/rbd/controllerserver.go
index 20f3a868b..d12e35739 100644
--- a/internal/rbd/controllerserver.go
+++ b/internal/rbd/controllerserver.go
@@ -175,6 +175,33 @@ func getGRPCErrorForCreateVolume(err error) error {
 	return status.Error(codes.Internal, err.Error())
 }
 
+// validateRequestedVolumeSize validates the request volume size with the
+// source snapshot or volume size, if there is a size missmatch it returns an error.
+func validateRequestedVolumeSize(rbdVol, parentVol *rbdVolume, rbdSnap *rbdSnapshot, cr *util.Credentials) error {
+	if rbdSnap != nil {
+		vol := generateVolFromSnap(rbdSnap)
+		err := vol.Connect(cr)
+		if err != nil {
+			return status.Error(codes.Internal, err.Error())
+		}
+		defer vol.Destroy()
+
+		err = vol.getImageInfo()
+		if err != nil {
+			return status.Error(codes.Internal, err.Error())
+		}
+		if rbdVol.VolSize != vol.VolSize {
+			return status.Errorf(codes.InvalidArgument, "size missmatch, requested volume size %d and source snapshot size %d", rbdVol.VolSize, vol.VolSize)
+		}
+	}
+	if parentVol != nil {
+		if rbdVol.VolSize != parentVol.VolSize {
+			return status.Errorf(codes.InvalidArgument, "size missmatch, requested volume size %d and source volume size %d", rbdVol.VolSize, parentVol.VolSize)
+		}
+	}
+	return nil
+}
+
 // CreateVolume creates the volume in backend
 func (cs *ControllerServer) CreateVolume(ctx context.Context, req *csi.CreateVolumeRequest) (*csi.CreateVolumeResponse, error) {
 	if err := cs.validateVolumeReq(ctx, req); err != nil {
@@ -227,6 +254,11 @@ func (cs *ControllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 		return buildCreateVolumeResponse(ctx, req, rbdVol)
 	}
 
+	err = validateRequestedVolumeSize(rbdVol, parentVol, rbdSnap, cr)
+	if err != nil {
+		return nil, err
+	}
+
 	err = flattenParentImage(ctx, parentVol, cr)
 	if err != nil {
 		return nil, err