From 8eee54be73f4b938dbf48e95c0dbecb5f19b08ee Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 21 Jun 2016 00:12:26 +0200 Subject: [PATCH] netfilter: nft_hash: support deletion of inactive elements New elements are inactive in the preparation phase, and its NFT_SET_ELEM_BUSY_MASK flag is set on. This busy flag doesn't allow us to delete it from the same transaction, following a sequence like: begin transaction add element X delete element X end transaction This sequence is valid and may be triggered by robots. To resolve this problem, allow deactivating elements that are active in the current generation (ie. those that has been just added in this batch). Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_hash.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c index 6fa016564f90..d3a507d3f192 100644 --- a/net/netfilter/nft_hash.c +++ b/net/netfilter/nft_hash.c @@ -153,9 +153,10 @@ static void *nft_hash_deactivate(const struct nft_set *set, const struct nft_set_elem *elem) { struct nft_hash *priv = nft_set_priv(set); + struct net *net = read_pnet(&set->pnet); struct nft_hash_elem *he; struct nft_hash_cmp_arg arg = { - .genmask = nft_genmask_next(read_pnet(&set->pnet)), + .genmask = nft_genmask_next(net), .set = set, .key = elem->key.val.data, }; @@ -163,7 +164,8 @@ static void *nft_hash_deactivate(const struct nft_set *set, rcu_read_lock(); he = rhashtable_lookup_fast(&priv->ht, &arg, nft_hash_params); if (he != NULL) { - if (!nft_set_elem_mark_busy(&he->ext)) + if (!nft_set_elem_mark_busy(&he->ext) || + !nft_is_active(net, &he->ext)) nft_set_elem_change_active(set, &he->ext); else he = NULL; -- 2.30.2