Subject: Re: [PATCH v2] ipv4: netfilter: always let NUL terminated string ended by '\0'

From: Pablo Neira Ayuso <[email-masked]>
Date: Thu, 23 May 2013 14:26:31 +0200

On Thu, May 23, 2013 at 07:50:46PM +0800, Chen Gang wrote:
> 
> For NUL terminated string, need always be sure of ended by '\0'.
> 
> 'prefix' max length is 128 (NF_LOG_PREFIXLEN), and 'pm->prefix' max
> length is 32 (ULOG_PREFIX_LEN), so really need notice it.
> 
> 'pm' is 'struct ulog_packet_msg_t' which may be copied to user mode
> (defined in "include/uapi/..."), so can not use strlcpy() instead of.

That's fixing a real bug. We're passing strings that are longer than
32 bytes from nf_conntrack_tcp via nf_log, if ipt_ULOG is used, it
will pass a non-null terminated string.

I'm going to rework the patch description to include this and apply
this patch.

Thanks Chen.