diff --git a/client/cmdhfmfu.c b/client/cmdhfmfu.c
index 3f8982997..e5e18952a 100644
--- a/client/cmdhfmfu.c
+++ b/client/cmdhfmfu.c
@@ -1946,7 +1946,7 @@ int CmdHF14AMfURestore(const char *Cmd){
 			if (filelen > FILE_PATH_SIZE-5)
 				filelen = FILE_PATH_SIZE-5;
 			
-			if (filelen < 0)
+			if (filelen < 1)
 				sprintf(filename, "dumpdata.bin");
 
 			cmdp += 2;