Re: [PATCH nf] netfilter: nf_tables: add rescheduling points during loop detection walks

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Tue, Jul 26, 2022 at 12:44:35PM +0200, Florian Westphal wrote:
> Add explicit rescheduling points during ruleset walk.
> 
> Switching to a faster algorithm is possible but this is a much
> smaller change, suitable for nf tree.
> 
> Link: https://bugzilla.netfilter.org/show_bug.cgi?id=1460

Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>

> Signed-off-by: Florian Westphal <fw@strlen.de>
> ---
>  net/netfilter/nf_tables_api.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
> index 646d5fd53604..9f976b11d896 100644
> --- a/net/netfilter/nf_tables_api.c
> +++ b/net/netfilter/nf_tables_api.c
> @@ -3340,6 +3340,8 @@ int nft_chain_validate(const struct nft_ctx *ctx, const struct nft_chain *chain)
>  			if (err < 0)
>  				return err;
>  		}
> +
> +		cond_resched();
>  	}
>  
>  	return 0;
> @@ -9367,9 +9369,13 @@ static int nf_tables_check_loops(const struct nft_ctx *ctx,
>  				break;
>  			}
>  		}
> +
> +		cond_resched();
>  	}
>  
>  	list_for_each_entry(set, &ctx->table->sets, list) {
> +		cond_resched();
> +
>  		if (!nft_is_active_next(ctx->net, set))
>  			continue;
>  		if (!(set->flags & NFT_SET_MAP) ||
> -- 
> 2.35.1
>