Subject: Re: [PATCH net-next 2/9] net/ipv4: Plumb support for filtering route dumps

From: Andrew Lunn <[email-masked]>
Date: Thu, 11 Oct 2018 17:56:30 +0200

> @@ -866,10 +866,13 @@ static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
>  		hlist_for_each_entry_rcu(tb, head, tb_hlist) {
>  			if (e < s_e)
>  				goto next;
> +			if (filter.table_id && filter.table_id != tb->tb_id)
> +				goto next;
> +

Hi David

Should there be a test here that filter->filter_set is set, before
looking at filter.table_id.

>  			if (dumped)
>  				memset(&cb->args[2], 0, sizeof(cb->args) -
>  						 2 * sizeof(cb->args[0]));
> -			err = fib_table_dump(tb, skb, cb);
> +			err = fib_table_dump(tb, skb, cb, &filter);
>  			if (err < 0) {
>  				if (likely(skb->len))
>  					goto out;
> diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
> index 5bc0c89e81e4..237c9f72b265 100644
> --- a/net/ipv4/fib_trie.c
> +++ b/net/ipv4/fib_trie.c
> @@ -2003,12 +2003,17 @@ void fib_free_table(struct fib_table *tb)
>  }
>  
>  static int fn_trie_dump_leaf(struct key_vector *l, struct fib_table *tb,
> -			     struct sk_buff *skb, struct netlink_callback *cb)
> +			     struct sk_buff *skb, struct netlink_callback *cb,
> +			     struct fib_dump_filter *filter)
>  {
> +	unsigned int flags = NLM_F_MULTI;
>  	__be32 xkey = htonl(l->key);
>  	struct fib_alias *fa;
>  	int i, s_i;
>  
> +	if (filter->filter_set)
> +		flags |= NLM_F_DUMP_FILTERED;

With the above code, it seems like table_id could be filtered without
setting this flag to indicate some filters have been applied?

	Andrew