dccp: Fix memleak in __feat_register_sp

commit 1d3ff09 upstream.

If dccp_feat_push_change fails, we forget free the mem
which is alloced by kmemdup in dccp_feat_clone_sp_val.

Reported-by: Hulk Robot <[email protected]>
Fixes: e8ef967 ("dccp: Registration routines for changing feature values")
Reviewed-by: Mukesh Ojha <[email protected]>
Signed-off-by: YueHaibing <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Ben Hutchings <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: YueHaibing

net/dccp/feat.c

@@ -738,7 +738,12 @@ static int __feat_register_sp(struct list_head *fn, u8 feat, u8 is_local,
 	if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len))
 		return -ENOMEM;
 
-	return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
+	if (dccp_feat_push_change(fn, feat, is_local, mandatory, &fval)) {
+		kfree(fval.sp.vec);
+		return -ENOMEM;
+	}
+
+	return 0;
 }
 
 /**