Kernel sends an empty NFTA_SET_USERDATA attribute with no value if
userspace adds a set 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@xxxxxxxxxxxxx>
---
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 fd814e514f94..71e501c5ad21 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3770,7 +3770,8 @@ 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;
nest = nla_nest_start_noflag(skb, NFTA_SET_DESC);
--
2.20.1
