Krzysztof Piotr Oledzki wrote:
>>From 187703b8bfc30048c3a973fea6d3b3ce9bcbb49a Mon Sep 17 00:00:00 2001
> From: Krzysztof Piotr Oledzki <ole@ans.pl>
> Date: Mon, 7 Jul 2008 21:49:57 +0200
> Subject: netfilter: accounting rework: ct_extend + 64bit counters (v4)
> 
> Initially netfilter has had 64bit counters for conntrack-based accounting, but
> it was changed in 2.6.14 to save memory. Unfortunately in-kernel 64bit counters are
> still required, for example for "connbytes" extension. However, 64bit counters
> waste a lot of memory and it was not possible to enable/disable it runtime.
> 
> This patch:
>  - reimplements accounting with respect to the extension infrastructure,
>  - makes one global version of seq_print_acct() instead of two seq_print_counters(),
>  - makes it possible to enable it at boot time (for CONFIG_SYSCTL/CONFIG_SYSFS=n),
>  - makes it possible to enable/disable it at runtime by sysctl or sysfs,
>  - extends counters from 32bit to 64bit,
>  - renames ip_conntrack_counter -> nf_conn_counter,
>  - enables accounting code unconditionally (no longer depends on CONFIG_NF_CT_ACCT),
>  - set initial accounting enable state based on CONFIG_NF_CT_ACCT
>  - removes buggy IPCT_COUNTER_FILLING event handling.
> 
> If accounting is enabled newly created connections get additional acct extend.
> Old connections are not changed as it is not possible to add a ct_extend area
> to confirmed conntrack. Accounting is performed for all connections with
> acct extend regardless of a current state of "net.netfilter.nf_conntrack_acct".

Applied with the attached minor cleanups. Thanks Krzysztof!

There is one things I think needs fixing however:

>  			if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
> -						IPCTNL_MSG_CT_GET_CTRZERO)
> -				memset(&ct->counters, 0, sizeof(ct->counters));
> -#endif
> +						IPCTNL_MSG_CT_GET_CTRZERO) {
> +				struct nf_conn_counter *acct;
> +
> +				acct = nf_conn_acct_find(ct);
> +				if (acct)
> +					memset(acct, 0, sizeof(struct nf_conn_counter[IP_CT_DIR_MAX]));

This needs locking.