fix(sharestorageprovider): Stat resource when resolving share by path

When resolving a received shared by mountpath, make sure that the
shared resource actually exists. This avoids issues with dangling shares
for already delete resources using the same mountpoint.

Fixes: owncloud/ocis#7895

changelog/unreleased/fix-stat-recreated-share.md

@@ -0,0 +1,8 @@
+Bugfix: Fix Stat() by Path on re-created resource
+
+We fixed bug that caused Stat Requests using a Path reference to a mount point
+in the sharejail to not resolve correctly, when a share using the same
+mount point to an already deleted resource was still existing.
+
+https://github.com/cs3org/reva/pull/xxx
+https://github.com/owncloud/ocis/issues/7895

internal/grpc/services/sharesstorageprovider/sharesstorageprovider.go

@@ -1057,9 +1057,11 @@ func (s *service) resolveAcceptedShare(ctx context.Context, ref *provider.Refere
 		return lsRes.Share, lsRes.Status, nil
 	}
 
-	// we currently need to list all shares and match the path if the request is relative to the share jail root
+	// we currently need to list all accepted shares and match the path if the
+	// request is relative to the share jail root. Also we need to Stat() the
+	// shared resource's id to check whether that still exist. There might be
+	// old shares using the same path but for an already vanished resource id.
 	if ref.ResourceId.OpaqueId == utils.ShareStorageProviderID && ref.Path != "." {
-		// we need to list accepted shares and match the path
 		lsRes, err := sharingCollaborationClient.ListReceivedShares(ctx, &collaboration.ListReceivedSharesRequest{
 			Filters: []*collaboration.Filter{
 				{
@@ -1079,10 +1081,31 @@ func (s *service) resolveAcceptedShare(ctx context.Context, ref *provider.Refere
 		}
 		for _, receivedShare := range lsRes.Shares {
 			if isMountPointForPath(receivedShare.MountPoint.Path, ref.Path) {
+				// Only return this share if the resource still exists.
+				gatewayClient, err := s.gatewaySelector.Next()
+				if err != nil {
+					return nil, nil, err
+				}
+				sRes, err := gatewayClient.Stat(ctx, &provider.StatRequest{
+					Ref: &provider.Reference{ResourceId: receivedShare.GetShare().GetResourceId()},
+				})
+				if err != nil {
+					appctx.GetLogger(ctx).Debug().
+						Err(err).
+						Interface("resourceID", receivedShare.GetShare().GetResourceId()).
+						Msg("resolveAcceptedShare: failed to stat shared resource")
+					continue
+				}
+				if sRes.Status.Code != rpc.Code_CODE_OK {
+					appctx.GetLogger(ctx).Debug().
+						Interface("resourceID", receivedShare.GetShare().GetResourceId()).
+						Interface("status", sRes.Status).
+						Msg("resolveAcceptedShare: failed to stat shared resource")
+					continue
+				}
 				return receivedShare, lsRes.Status, nil
 			}
 		}
-
 	}
 
 	return nil, status.NewNotFound(ctx, "sharesstorageprovider: not found "+ref.String()), nil

internal/grpc/services/sharesstorageprovider/sharesstorageprovider_test.go

@@ -261,7 +261,23 @@ var _ = Describe("Sharesstorageprovider", func() {
 						},
 					}
 				default:
-					if req.Ref.ResourceId.OpaqueId == "shareddir-merged" {
+					switch req.Ref.ResourceId.OpaqueId {
+					case "shareddir", "shareddir2":
+						permissionSet := &sprovider.ResourcePermissions{
+							Stat:          true,
+							ListContainer: true,
+						}
+						return &sprovider.StatResponse{
+							Status: status.NewOK(context.Background()),
+							Info: &sprovider.ResourceInfo{
+								Type:          sprovider.ResourceType_RESOURCE_TYPE_CONTAINER,
+								Path:          "share1-shareddir",
+								Id:            req.Ref.ResourceId,
+								PermissionSet: permissionSet,
+								Size:          100,
+							},
+						}
+					case "shareddir-merged":
 						permissionSet := &sprovider.ResourcePermissions{
 							Stat:          true,
 							ListContainer: true,
@@ -280,9 +296,10 @@ var _ = Describe("Sharesstorageprovider", func() {
 								Size:          100,
 							},
 						}
-					}
-					return &sprovider.StatResponse{
-						Status: status.NewNotFound(context.Background(), "not found"),
+					default:
+						return &sprovider.StatResponse{
+							Status: status.NewNotFound(context.Background(), "not found"),
+						}
 					}
 				}
 			},