netfilter: nf_tables: don't unregister hook when table is dormant

When nf_tables_updchain encounters an error, hook registration needs to
be rolled back.

This should only be done if the hook has been registered, which won't
happen when the table is flagged as dormant (inactive).

Just move the assignment into the registration block.

Reported-by: syzbot+53ed3a6440173ddbf499@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=53ed3a6440173ddbf499
Fixes: b9703ed44ffb ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index c2df81b7e95056c8ccf508a65675851105b1acfb..a133e1c175ce9c815ca5f19f9ae762928d87d976 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2839,11 +2839,11 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy,
                        err = nft_netdev_register_hooks(ctx->net, &hook.list);
                        if (err < 0)
                                goto err_hooks;
+
+                       unregister = true;
                }
        }
 
-       unregister = true;
-
        if (nla[NFTA_CHAIN_COUNTERS]) {
                if (!nft_is_base_chain(chain)) {
                        err = -EOPNOTSUPP;