Re: [PATCH] netfilter: Zero the tuple in nfnl_cthelper_parse_tuple()

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

On Thu, Mar 12, 2015 at 09:37:58AM +0000, Ian Wilson wrote:
> nfnl_cthelper_parse_tuple() is called from nfnl_cthelper_new(),
> nfnl_cthelper_get() and nfnl_cthelper_del().  In each case they pass
> a pointer to an nf_conntrack_tuple data structure local variable:
> 
>     struct nf_conntrack_tuple tuple;
>     ...
>     ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
> 
> The problem is that this local variable is not initialized, and
> nfnl_cthelper_parse_tuple() only initializes two fields: src.l3num and
> dst.protonum.  This leaves all other fields with undefined values
> based on whatever is on the stack:
> 
>     tuple->src.l3num = ntohs(nla_get_be16(tb[NFCTH_TUPLE_L3PROTONUM]));
>     tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]);
> 
> The symptom observed was that when the rpc and tns helpers were added
> then traffic to port 1536 was being sent to user-space.

Applied, thanks. I'll pass this to -stable too.