fix: add defer cleanup for file handles, fix symlink permissions with followLinks

Author: rgarcia

lib/guest/client.go

@@ -467,6 +467,13 @@ func CopyFromInstance(ctx context.Context, vsockSocketPath string, opts CopyFrom
 	var currentFile *os.File
 	var currentHeader *CopyFromGuestHeader
 
+	// Ensure file is closed on error paths
+	defer func() {
+		if currentFile != nil {
+			currentFile.Close()
+		}
+	}()
+
 	for {
 		resp, err := stream.Recv()
 		if err == io.EOF {

lib/system/guest_agent/main.go

@@ -640,7 +640,14 @@ func (s *guestServer) copyFromGuestDir(rootPath string, followLinks bool, stream
 			return nil
 		}
 
-		info, err := d.Info()
+		// Use os.Stat when followLinks is true to get the target's info
+		// Use d.Info() (same as os.Lstat) when followLinks is false to get symlink's info
+		var info os.FileInfo
+		if followLinks {
+			info, err = os.Stat(path)
+		} else {
+			info, err = d.Info()
+		}
 		if err != nil {
 			stream.Send(&pb.CopyFromGuestResponse{
 				Response: &pb.CopyFromGuestResponse_Error{