This is a note to let you know that I've just added the patch titled
netfilter: nf_tables: disallow element removal on anonymous sets
to the 4.19-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-disallow-element-removal-on-anon.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f7826c261f6f895527a86ec4e7bdc2ef68d358a6
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Sun Sep 10 19:04:45 2023 +0200
netfilter: nf_tables: disallow element removal on anonymous sets
[ Upstream commit 23a3bfd4ba7acd36abf52b78605f61b21bdac216 ]
Anonymous sets need to be populated once at creation and then they are
bound to rule since 938154b93be8 ("netfilter: nf_tables: reject unbound
anonymous set before commit phase"), otherwise transaction reports
EINVAL.
Userspace does not need to delete elements of anonymous sets that are
not yet bound, reject this with EOPNOTSUPP.
From flush command path, skip anonymous sets, they are expected to be
bound already. Otherwise, EINVAL is hit at the end of this transaction
for unbound sets.
Fixes: 96518518cc41 ("netfilter: add nftables")
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 0ff8f1006c6b9..3e30441162896 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -993,8 +993,7 @@ static int nft_flush_table(struct nft_ctx *ctx)
if (!nft_is_active_next(ctx->net, set))
continue;
- if (nft_set_is_anonymous(set) &&
- !list_empty(&set->bindings))
+ if (nft_set_is_anonymous(set))
continue;
err = nft_delset(ctx, set);
@@ -4902,8 +4901,10 @@ static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
if (IS_ERR(set))
return PTR_ERR(set);
- if (!list_empty(&set->bindings) &&
- (set->flags & (NFT_SET_CONSTANT | NFT_SET_ANONYMOUS)))
+ if (nft_set_is_anonymous(set))
+ return -EOPNOTSUPP;
+
+ if (!list_empty(&set->bindings) && (set->flags & NFT_SET_CONSTANT))
return -EBUSY;
if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL) {
