Patch "netfilter: nf_tables: release batch on table validation from abort path" has been added to the 5.4-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: release batch on table validation from abort path

to the 5.4-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-release-batch-on-table-validatio.patch
and it can be found in the queue-5.4 subdirectory.

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



commit ad37072269f6340c7188924145f4fd92ac3b77cc
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date:   Mon Apr 8 23:21:40 2024 +0200

    netfilter: nf_tables: release batch on table validation from abort path
    
    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@xxxxxxxxxxxxxxx
    Fixes: c0391b6ab810 ("netfilter: nf_tables: missing validation from the abort path")
    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 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);