Patch "netfilter: nf_tables: reject unbound chain set before commit phase" has been added to the 6.3-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    netfilter: nf_tables: reject unbound chain set before commit phase

to the 6.3-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     netfilter-nf_tables-reject-unbound-chain-set-before-.patch
and it can be found in the queue-6.3 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 4a33577f598b4a39f41ffcaefdcee32b69c4df86
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date:   Fri Jun 16 15:21:39 2023 +0200

    netfilter: nf_tables: reject unbound chain set before commit phase
    
    [ Upstream commit 62e1e94b246e685d89c3163aaef4b160e42ceb02 ]
    
    Use binding list to track set transaction and to check for unbound
    chains before entering the commit phase.
    
    Bail out if chain binding remain unused before entering the commit
    step.
    
    Fixes: d0e2c7de92c7 ("netfilter: nf_tables: add NFT_CHAIN_BINDING")
    Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 2e3a374db1b9f..f065542750376 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -372,6 +372,11 @@ static void nft_trans_commit_list_add_tail(struct net *net, struct nft_trans *tr
 		    nft_set_is_anonymous(nft_trans_set(trans)))
 			list_add_tail(&trans->binding_list, &nft_net->binding_list);
 		break;
+	case NFT_MSG_NEWCHAIN:
+		if (!nft_trans_chain_update(trans) &&
+		    nft_chain_binding(nft_trans_chain(trans)))
+			list_add_tail(&trans->binding_list, &nft_net->binding_list);
+		break;
 	}
 
 	list_add_tail(&trans->list, &nft_net->commit_list);
@@ -9419,6 +9424,14 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
 				return -EINVAL;
 			}
 			break;
+		case NFT_MSG_NEWCHAIN:
+			if (!nft_trans_chain_update(trans) &&
+			    nft_chain_binding(nft_trans_chain(trans)) &&
+			    !nft_trans_chain_bound(trans)) {
+				pr_warn_once("nftables ruleset with unbound chain\n");
+				return -EINVAL;
+			}
+			break;
 		}
 	}