Don't segfault on unknown format specifiers

diff --git a/lib/headerfmt.c b/lib/headerfmt.c
index 1c05c89..2800d19 100644 (file)
--- a/lib/headerfmt.c
+++ b/lib/headerfmt.c
@@ -256,7 +256,7 @@ bingo:
     if (stag->type != NULL)
        stag->fmt = rpmHeaderFormatFuncByName(stag->type);
 
-    return 0;
+    return stag->fmt ? 0 : 1;
 }
 
 /* forward ref */