[PATCH 4.19 22/88] netfilter: nf_tables: add NFTA_SET_USERDATA if not null

Greg Kroah-Hartman
2020-09-08T19:02:16Z

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

[ Upstream commit 6f03bf43ee05b31d3822def2a80f11b3591c55b3 ]

Kernel sends an empty NFTA_SET_USERDATA attribute with no value if
userspace adds a set with no NFTA_SET_USERDATA attribute.

Fixes: e6d8ecac9e68 ("netfilter: nf_tables: Add new attributes into nft_set to store user data.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netfilter/nf_tables_api.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 1b8a53081632f..159ec1533c980 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3204,7 +3204,8 @@ static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
goto nla_put_failure;
}

- if (nla_put(skb, NFTA_SET_USERDATA, set->udlen, set->udata))
+ if (set->udata &&
+ nla_put(skb, NFTA_SET_USERDATA, set->udlen, set->udata))
goto nla_put_failure;

desc = nla_nest_start(skb, NFTA_SET_DESC);
--
2.25.1