Address user reported coverity issues.
diff --git a/programs/pkey/rsa_sign_pss.c b/programs/pkey/rsa_sign_pss.c
index c045a04..7b6f14d 100644
--- a/programs/pkey/rsa_sign_pss.c
+++ b/programs/pkey/rsa_sign_pss.c
@@ -153,6 +153,7 @@
     if( fwrite( buf, 1, olen, f ) != olen )
     {
         mbedtls_printf( "failed\n  ! fwrite failed\n\n" );
+        fclose( f );
         goto exit;
     }