From dae9b4fd831031122eab834c4eb1ef4c37ef1b93 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Tue, 20 Sep 2022 17:07:03 +0800 Subject: [PATCH] netfilter: nf_tables: do not allow CHAIN_ID to refer to another table stable inclusion from stable-v5.10.137 commit 9e7dcb88ec8e85e4a8ad0ea494ea2f90f32d2583 category: bugfix bugzilla: 187457, https://gitee.com/src-openeuler/kernel/issues/I5MEZD CVE: CVE-2022-2586 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9e7dcb88ec8e85e4a8ad0ea494ea2f90f32d2583 -------------------------------- commit 95f466d22364a33d183509629d0879885b4f547e upstream. When doing lookups for chains on the same batch by using its ID, a chain from a different table can be used. If a rule is added to a table but refers to a chain in a different table, it will be linked to the chain in table2, but would have expressions referring to objects in table1. Then, when table1 is removed, the rule will not be removed as its linked to a chain in table2. When expressions in the rule are processed or removed, that will lead to a use-after-free. When looking for chains by ID, use the table that was used for the lookup by name, and only return chains belonging to that same table. Fixes: 837830a4b439 ("netfilter: nf_tables: add NFTA_RULE_CHAIN_ID attribute") Signed-off-by: Thadeu Lima de Souza Cascardo Cc: Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman Signed-off-by: Lu Wei Reviewed-by: Yue Haibing Reviewed-by: Xiu Jianfeng Signed-off-by: Zheng Zengkai --- net/netfilter/nf_tables_api.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 7b0497da2d94..373f9bd3fbb1 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2265,6 +2265,7 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy, } static struct nft_chain *nft_chain_lookup_byid(const struct net *net, + const struct nft_table *table, const struct nlattr *nla) { u32 id = ntohl(nla_get_be32(nla)); @@ -2274,6 +2275,7 @@ static struct nft_chain *nft_chain_lookup_byid(const struct net *net, struct nft_chain *chain = trans->ctx.chain; if (trans->msg_type == NFT_MSG_NEWCHAIN && + chain->table == table && id == nft_trans_chain_id(trans)) return chain; } @@ -3199,7 +3201,7 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk, return -EOPNOTSUPP; } else if (nla[NFTA_RULE_CHAIN_ID]) { - chain = nft_chain_lookup_byid(net, nla[NFTA_RULE_CHAIN_ID]); + chain = nft_chain_lookup_byid(net, table, nla[NFTA_RULE_CHAIN_ID]); if (IS_ERR(chain)) { NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN_ID]); return PTR_ERR(chain); @@ -8641,7 +8643,7 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data, tb[NFTA_VERDICT_CHAIN], genmask); } else if (tb[NFTA_VERDICT_CHAIN_ID]) { - chain = nft_chain_lookup_byid(ctx->net, + chain = nft_chain_lookup_byid(ctx->net, ctx->table, tb[NFTA_VERDICT_CHAIN_ID]); if (IS_ERR(chain)) return PTR_ERR(chain); -- GitLab