diff mbox series

[4.14,68/86] netfilter: nf_tables: do not allow RULE_ID to refer to another chain

Message ID 20230528190831.159343774@linuxfoundation.org
State Awaiting Upstream, archived
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman May 28, 2023, 7:10 p.m. UTC 
From: Pablo Neira Ayuso <pablo@netfilter.org>

[ 36d5b2913219ac853908b0f1c664345e04313856 ]

When doing lookups for rules on the same batch by using its ID, a rule from
a different chain can be used. If a rule is added to a chain but tries to
be positioned next to a rule from a different chain, it will be linked to
chain2, but the use counter on chain1 would be the one to be incremented.

When looking for rules by ID, use the chain that was used for the lookup by
name. The chain used in the context copied to the transaction needs to
match that same chain. That way, struct nft_rule does not need to get
enlarged with another member.

Fixes: 1a94e38d254b ("netfilter: nf_tables: add NFTA_RULE_ID attribute")
Fixes: 75dd48e2e420 ("netfilter: nf_tables: Support RULE_ID reference in new rule")
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/netfilter/nf_tables_api.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2475,6 +2475,7 @@  err1:
 }
 
 static struct nft_rule *nft_rule_lookup_byid(const struct net *net,
+					     const struct nft_chain *chain,
 					     const struct nlattr *nla)
 {
 	u32 id = ntohl(nla_get_be32(nla));
@@ -2484,6 +2485,7 @@  static struct nft_rule *nft_rule_lookup_
 		struct nft_rule *rule = nft_trans_rule(trans);
 
 		if (trans->msg_type == NFT_MSG_NEWRULE &&
+		    trans->ctx.chain == chain &&
 		    id == nft_trans_rule_id(trans))
 			return rule;
 	}
@@ -2530,7 +2532,7 @@  static int nf_tables_delrule(struct net
 
 			err = nft_delrule(&ctx, rule);
 		} else if (nla[NFTA_RULE_ID]) {
-			rule = nft_rule_lookup_byid(net, nla[NFTA_RULE_ID]);
+			rule = nft_rule_lookup_byid(net, chain, nla[NFTA_RULE_ID]);
 			if (IS_ERR(rule))
 				return PTR_ERR(rule);