[PATCH v2] audit: log nftables configuration change events once per table

[Pablo Neira Ayuso]

On Mon, Mar 22, 2021 at 04:49:04PM -0400, Richard Guy Briggs wrote:
> diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
> index c1eb5cdb3033..42ba44890523 100644
> --- a/net/netfilter/nf_tables_api.c
> +++ b/net/netfilter/nf_tables_api.c
[...]
> @@ -8006,12 +7938,47 @@ static void nft_commit_notify(struct net *net, u32 portid)
>  	WARN_ON_ONCE(!list_empty(&net->nft.notify_list));
>  }
>  
> +void nf_tables_commit_audit_collect(struct list_head *adl,
> +				    struct nft_trans *trans) {

nitpick: curly brace starts in the line.

> +	struct nft_audit_data *adp;
> +
> +	list_for_each_entry(adp, adl, list) {
> +		if (adp->table == trans->ctx.table)
> +			goto found;
> +	}
> +	adp = kzalloc(sizeof(*adp), GFP_KERNEL);

        if (!adp)
                ...

> +	adp->table = trans->ctx.table;
> +	INIT_LIST_HEAD(&adp->list);
> +	list_add(&adp->list, adl);
> +found:
> +	adp->entries++;
> +	if (!adp->op || adp->op > trans->msg_type)
> +		adp->op = trans->msg_type;
> +}
> +
> +#define AUNFTABLENAMELEN (NFT_TABLE_MAXNAMELEN + 22)
> +
> +void nf_tables_commit_audit_log(struct list_head *adl, u32 generation) {
                                                                          ^
same thing here

> +	struct nft_audit_data *adp, *adn;
> +	char aubuf[AUNFTABLENAMELEN];
> +
> +	list_for_each_entry_safe(adp, adn, adl, list) {
> +		snprintf(aubuf, AUNFTABLENAMELEN, "%s:%u", adp->table->name,
> +			 generation);
> +		audit_log_nfcfg(aubuf, adp->table->family, adp->entries,
> +				nft2audit_op[adp->op], GFP_KERNEL);
> +		list_del(&adp->list);
> +		kfree(adp);
> +	}
> +}
> +
>  static int nf_tables_commit(struct net *net, struct sk_buff *skb)
>  {
>  	struct nft_trans *trans, *next;
>  	struct nft_trans_elem *te;
>  	struct nft_chain *chain;
>  	struct nft_table *table;
> +	LIST_HEAD(adl);
>  	int err;
>  
>  	if (list_empty(&net->nft.commit_list)) {
> @@ -8206,12 +8173,15 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
>  			}
>  			break;
>  		}
> +		nf_tables_commit_audit_collect(&adl, trans);
>  	}
>  
>  	nft_commit_notify(net, NETLINK_CB(skb).portid);
>  	nf_tables_gen_notify(net, skb, NFT_MSG_NEWGEN);
>  	nf_tables_commit_release(net);
>  
> +	nf_tables_commit_audit_log(&adl, net->nft.base_seq);
> +

This looks more self-contained and nicer, thanks.