[PATCH 5.3 048/135] netfilter: nf_tables: bogus EOPNOTSUPP on basechain update

From: Greg Kroah-Hartman
Date: Tue Dec 03 2019 - 18:10:17 EST


From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

[ Upstream commit 1ed012f6fd83e7ee7efd22e2c32f23efff015b30 ]

Userspace never includes the NFT_BASE_CHAIN flag, this flag is inferred
from the NFTA_CHAIN_HOOK atribute. The chain update path does not allow
to update flags at this stage, the existing sanity check bogusly hits
EOPNOTSUPP in the basechain case if the offload flag is set on.

Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 3b81323fa0171..5dbc6bfb532cd 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1922,6 +1922,7 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
if (nlh->nlmsg_flags & NLM_F_REPLACE)
return -EOPNOTSUPP;

+ flags |= chain->flags & NFT_BASE_CHAIN;
return nf_tables_updchain(&ctx, genmask, policy, flags);
}

--
2.20.1