[PATCH 5.14 054/151] netfilter: nf_tables: reverse order in rule replacement expansion

[Greg Kroah-Hartman]

From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

[ Upstream commit 2c964c558641a3bddaee5719c9e6d8805f777812 ]

Deactivate old rule first, then append the new rule, so rule replacement
notification via netlink first reports the deletion of the old rule with
handle X in first place, then it adds the new rule (reusing the handle X
of the replaced old rule).

Note that the abort path releases the transaction that has been created
by nft_delrule() on error.

Fixes: ca08987885a1 ("netfilter: nf_tables: deactivate expressions in rule replecement routine")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/netfilter/nf_tables_api.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 085783b14075..c8acd26c7201 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3419,17 +3419,15 @@ static int nf_tables_newrule(struct sk_buff *skb, const struct nfnl_info *info,
 	}
 
 	if (info->nlh->nlmsg_flags & NLM_F_REPLACE) {
+		err = nft_delrule(&ctx, old_rule);
+		if (err < 0)
+			goto err_destroy_flow_rule;
+
 		trans = nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule);
 		if (trans == NULL) {
 			err = -ENOMEM;
 			goto err_destroy_flow_rule;
 		}
-		err = nft_delrule(&ctx, old_rule);
-		if (err < 0) {
-			nft_trans_destroy(trans);
-			goto err_destroy_flow_rule;
-		}
-
 		list_add_tail_rcu(&rule->list, &old_rule->list);
 	} else {
 		trans = nft_trans_rule_add(&ctx, NFT_MSG_NEWRULE, rule);
-- 
2.33.0