From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B129627442; Tue, 17 Sep 2024 20:24:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.188.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726604693; cv=none; b=l04+lz3fMfwj5ac+tDHe567qakU0zeLvcydG8KMrskshzy7c01Jy2lfgciH6mHU3LKIcQPWeD/PfHnqx+VdzTWfmMyWd9clvmlK7/b+xcwxPnAslr4UVrameiTyfBmYhp6M1G2b/j3rr1kD/lo/J3ZIMAMdyjYeMcoDxH2k2htw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726604693; c=relaxed/simple; bh=sAXL5REFErOAIq72y1hD/tmlcEw6FH8vBGdLH/Gb6m0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=IrBjF0R3e4Rm0OrDV9RmTdH+DVR9EFoapVJKM9tOrr+RdLsxxV6BQDsnppZSYrDl3mJ6wKKOFVl5EsV72odJ6bqbU6mw1GiSOS8wfrIPAphcpE08YaDIARP7/wr8sdHK9IFHIxw7ZIujDSeVnR6z2BfsmYt38cq2icvzsjxz9S0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; arc=none smtp.client-ip=217.70.188.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: gregkh@linuxfoundation.org, sashal@kernel.org, stable@vger.kernel.org Subject: [PATCH -stable,6.6 1/2] netfilter: nft_set_pipapo: walk over current view on netlink dump Date: Tue, 17 Sep 2024 22:24:43 +0200 Message-Id: <20240917202444.171526-2-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20240917202444.171526-1-pablo@netfilter.org> References: <20240917202444.171526-1-pablo@netfilter.org> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit commit 29b359cf6d95fd60730533f7f10464e95bd17c73 upstream. 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: 2b84e215f874 ("netfilter: nft_set_pipapo: .walk does not deal with generations") Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 13 +++++++++++++ net/netfilter/nf_tables_api.c | 5 +++++ net/netfilter/nft_set_pipapo.c | 5 +++-- 3 files changed, 21 insertions(+), 2 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 8af2543520b9..1b95c34a4e3d 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -297,9 +297,22 @@ 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; diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index fc99a5e91829..da5684e3fd08 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -628,6 +628,7 @@ 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, }; @@ -5392,6 +5393,7 @@ 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; @@ -5467,6 +5469,7 @@ 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, }; @@ -5845,6 +5848,7 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb) args.skb = skb; args.reset = reset; 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; @@ -7246,6 +7250,7 @@ static int nft_set_flush(struct nft_ctx *ctx, struct nft_set *set, u8 genmask) { struct nft_set_iter iter = { .genmask = genmask, + .type = NFT_ITER_UPDATE, .fn = nft_setelem_flush, }; diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c index e4dd73093048..90f129f1a136 100644 --- a/net/netfilter/nft_set_pipapo.c +++ b/net/netfilter/nft_set_pipapo.c @@ -2037,13 +2037,14 @@ 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); const struct nft_pipapo_match *m; const 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; -- 2.30.2