[PATCH 5.4 202/215] netfilter: nf_tables: release batch on table validation from abort path

Greg Kroah-Hartman
2024-04-11T10:23:54Z

From: Pablo Neira Ayuso <pablo@netfilter.org>

commit a45e6889575c2067d3c0212b6bc1022891e65b91 upstream.

Unlike early commit path stage which triggers a call to abort, an
explicit release of the batch is required on abort, otherwise mutex is
released and commit_list remains in place.

Add WARN_ON_ONCE to ensure commit_list is empty from the abort path
before releasing the mutex.

After this patch, commit_list is always assumed to be empty before
grabbing the mutex, therefore

03c1f1ef1584 ("netfilter: Cleanup nft_net->module_list from nf_tables_exit_net()")

only needs to release the pending modules for registration.

Cc: stable@vger.kernel.org
Fixes: c0391b6ab810 ("netfilter: nf_tables: missing validation from the abort path")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nf_tables_api.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index f4821d64c2fd8..b719f3517caf1 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -7564,10 +7564,11 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action)
struct nftables_pernet *nft_net = net_generic(net, nf_tables_net_id);
struct nft_trans *trans, *next;
struct nft_trans_elem *te;
+ int err = 0;

if (action == NFNL_ABORT_VALIDATE &&
nf_tables_validate(net) < 0)
- return -EAGAIN;
+ err = -EAGAIN;

list_for_each_entry_safe_reverse(trans, next, &nft_net->commit_list,
list) {
@@ -7700,7 +7701,7 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action)
else
nf_tables_module_autoload_cleanup(net);

- return 0;
+ return err;
}

static int nf_tables_abort(struct net *net, struct sk_buff *skb,
@@ -7714,6 +7715,8 @@ static int nf_tables_abort(struct net *net, struct sk_buff *skb,
ret = __nf_tables_abort(net, action);
nft_gc_seq_end(nft_net, gc_seq);

+ WARN_ON_ONCE(!list_empty(&nft_net->commit_list));
+
mutex_unlock(&nft_net->commit_mutex);

return ret;
@@ -8400,8 +8403,11 @@ static void __net_exit nf_tables_exit_net(struct net *net)

gc_seq = nft_gc_seq_begin(nft_net);

- if (!list_empty(&nft_net->commit_list))
- __nf_tables_abort(net, NFNL_ABORT_NONE);
+ WARN_ON_ONCE(!list_empty(&nft_net->commit_list));
+
+ if (!list_empty(&nft_net->module_list))
+ nf_tables_module_autoload_cleanup(net);
+
__nft_release_tables(net);

nft_gc_seq_end(nft_net, gc_seq);
--
2.43.0