This is a note to let you know that I've just added the patch titled netfilter: nf_tables: add NFTA_SET_USERDATA if not null to the 4.9-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-add-nfta_set_userdata-if-not-nul.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 400daa80e37fcc35eb5a6bcc00b12ab550103b68 Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Date: Thu Aug 20 14:12:54 2020 +0200 netfilter: nf_tables: add NFTA_SET_USERDATA if not null [ 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@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 2fa1c4f2e94e0..ec460aedfc617 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2592,7 +2592,8 @@ 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);