5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Florian Westphal fw@strlen.de
[ Upstream commit 08e4c8c5919fd405a4d709b4ba43d836894a26eb ]
If a transaction is aborted, we should mark the to-be-released NEWSET dead, just like commit path does for DEL and DESTROYSET commands.
In both cases all remaining elements will be released via set->ops->destroy().
The existing abort code does NOT post the actual release to the work queue. Also the entire __nf_tables_abort() function is wrapped in gc_seq begin/end pair.
Therefore, async gc worker will never try to release the pending set elements, as gc sequence is always stale.
It might be possible to speed up transaction aborts via work queue too, this would result in a race and a possible use-after-free.
So fix this before it becomes an issue.
Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane") Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 915df77161e1..9bd8ed0b62f1 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7604,6 +7604,7 @@ static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action) nft_trans_destroy(trans); break; } + nft_trans_set(trans)->dead = 1; list_del_rcu(&nft_trans_set(trans)->list); break; case NFT_MSG_DELSET: