From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [PATCH] netfilter: nf_tables: fix loop checking with set element data Date: Fri, 7 Feb 2014 15:51:05 +0000 Message-ID: <20140207155104.GA23911@macbook.localnet> References: <1391786631-4070-1-git-send-email-pablo@netfilter.org> <20140207154720.GA23148@macbook.localnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netfilter-devel@vger.kernel.org To: Pablo Neira Ayuso Return-path: Received: from stinky.trash.net ([213.144.137.162]:45444 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751699AbaBGPvI (ORCPT ); Fri, 7 Feb 2014 10:51:08 -0500 Content-Disposition: inline In-Reply-To: <20140207154720.GA23148@macbook.localnet> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Fri, Feb 07, 2014 at 03:47:34PM +0000, Patrick McHardy wrote: > On Fri, Feb 07, 2014 at 04:23:51PM +0100, Pablo Neira Ayuso wrote: > > This patch fixes two bugs: > > > > * Restrict the validation to verdict maps only, since struct nft_data > > is declared as a union, data[0] may contain the values -3 or -4 which > > match with NFT_JUMP and NFT_GOTO. I think this will result in crash > > while performing the chain loop validation. > > > > * Access to uninitialized data for end interval elements. The element > > data part is uninitialized in interval end elements. > > > > That's not necessary. The function is only invoked for NFT_DATA_VERDICT. > > > > Signed-off-by: Pablo Neira Ayuso > > --- > > net/netfilter/nf_tables_api.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c > > index d0c790e3e..522becb 100644 > > --- a/net/netfilter/nf_tables_api.c > > +++ b/net/netfilter/nf_tables_api.c > > @@ -2998,6 +2998,11 @@ static int nf_tables_loop_check_setelem(const struct nft_ctx *ctx, > > const struct nft_set_iter *iter, > > const struct nft_set_elem *elem) > > { > > + if (!(set->flags & NFT_SET_MAP) || > > + set->dtype != NFT_DATA_VERDICT || > > + elem->flags & NFT_SET_ELEM_INTERVAL_END) > > + return 0; > > + Right, I get the intention now. This function is only called for maps with dtype verdict, so just the check for SET_ELEM_INTERVAL_END is all we need. > > switch (elem->data.verdict) { > > case NFT_JUMP: > > case NFT_GOTO: > > -- > > 1.7.10.4 > -- > To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html