Commit 10ac25dc authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso Committed by Wang Hai
Browse files

netfilter: nft_set_pipapo: walk over current view on netlink dump 

mainline inclusion
from mainline-v6.9-rc5
commit 29b359cf6d95fd60730533f7f10464e95bd17c73
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9L5O8
CVE: CVE-2024-27017

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=29b359cf6d95fd60730533f7f10464e95bd17c73



--------------------------------

The generation mask can be updated while netlink dump is in progress.
The pipapo set backend walk iterator cannot rely on it to infer what
view of the datastructure is to be used. Add notation to specify if user
wants to read/update the set.

Based on patch from Florian Westphal.

Fixes: 2b84e215 ("netfilter: nft_set_pipapo: .walk does not deal with generations")
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>

Conflicts:
	include/net/netfilter/nf_tables.h
	net/netfilter/nf_tables_api.c
	net/netfilter/nft_set_pipapo.c
[e6ba7cb6 ("netfilter: nftables: add helper function to flush set
elements") is not applied, so there is no nft_set_flush() function.
Adaptation was made in nf_tables_delsetelem(). Other adaptations are
context conflicts.]
Signed-off-by: default avatarWang Hai <wanghai38@huawei.com>
parent 0982dad0

include/net/netfilter/nf_tables.h

+13 −0
Original line number Diff line number Diff line
@@ -262,9 +262,22 @@ struct nft_set_elem { 
	void			*priv;

};



/**

 * enum nft_iter_type - nftables set iterator type

 *

 * @NFT_ITER_READ: read-only iteration over set elements

 * @NFT_ITER_UPDATE: iteration under mutex to update set element state

 */

enum nft_iter_type {

	NFT_ITER_UNSPEC,

	NFT_ITER_READ,

	NFT_ITER_UPDATE,

};



struct nft_set;

struct nft_set_iter {

	u8		genmask;

	enum nft_iter_type type:8;

	unsigned int	count;

	unsigned int	skip;

	int		err;

net/netfilter/nf_tables_api.c

+6 −0
Original line number Diff line number Diff line
@@ -593,6 +593,7 @@ static void nft_map_deactivate(const struct nft_ctx *ctx, struct nft_set *set) 
{

	struct nft_set_iter iter = {

		.genmask	= nft_genmask_next(ctx->net),

		.type		= NFT_ITER_UPDATE,

		.fn		= nft_mapelem_deactivate,

	};
@@ -4727,6 +4728,7 @@ int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set, 
		}



		iter.genmask	= nft_genmask_next(ctx->net);

		iter.type	= NFT_ITER_UPDATE;

		iter.skip 	= 0;

		iter.count	= 0;

		iter.err	= 0;
@@ -4780,6 +4782,7 @@ static void nft_map_activate(const struct nft_ctx *ctx, struct nft_set *set) 
{

	struct nft_set_iter iter = {

		.genmask	= nft_genmask_next(ctx->net),

		.type		= NFT_ITER_UPDATE,

		.fn		= nft_mapelem_activate,

	};
@@ -5093,6 +5096,7 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) 
	args.cb			= cb;

	args.skb		= skb;

	args.iter.genmask	= nft_genmask_cur(net);

	args.iter.type		= NFT_ITER_READ;

	args.iter.skip		= cb->args[0];

	args.iter.count		= 0;

	args.iter.err		= 0;
@@ -6022,6 +6026,7 @@ static int nf_tables_delsetelem(struct net *net, struct sock *nlsk, 
	if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL) {

		struct nft_set_iter iter = {

			.genmask	= genmask,

			.type		= NFT_ITER_UPDATE,

			.fn		= nft_flush_set,

		};

		set->ops->walk(&ctx, set, &iter);
@@ -9131,6 +9136,7 @@ static int nf_tables_check_loops(const struct nft_ctx *ctx, 
				continue;



			iter.genmask	= nft_genmask_next(ctx->net);

			iter.type	= NFT_ITER_UPDATE;

			iter.skip 	= 0;

			iter.count	= 0;

			iter.err	= 0;

net/netfilter/nft_set_pipapo.c

+3 −2
Original line number Diff line number Diff line
@@ -2018,13 +2018,14 @@ static void nft_pipapo_walk(const struct nft_ctx *ctx, struct nft_set *set, 
			    struct nft_set_iter *iter)

{

	struct nft_pipapo *priv = nft_set_priv(set);

	struct net *net = read_pnet(&set->net);

	struct nft_pipapo_match *m;

	struct nft_pipapo_field *f;

	int i, r;



	WARN_ON_ONCE(iter->type == NFT_ITER_UNSPEC);



	rcu_read_lock();

	if (iter->genmask == nft_genmask_cur(net))

	if (iter->type == NFT_ITER_READ)

		m = rcu_dereference(priv->match);

	else

		m = priv->clone;