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

From: Pablo Neira Ayuso
Date: Mon Mar 22 2021 - 18:58:58 EST


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.