diff options
author | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-02-20 17:11:10 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-03-26 13:59:49 +0100 |
commit | 8f246228ca057df31225216063e198b25cea7a59 (patch) | |
tree | 75aeb6409a4dcd9ac458b560287ce4eae7c561a2 | |
parent | 0a12e44c18d25ba0b796cc49610430cbfd4676ec (diff) |
netfilter: nf_tables: fix addition/deletion of elements from commit/abort
commit 02263db00b6cb98701332aa257c07ca549c2324b upstream.
We have several problems in this path:
1) There is a use-after-free when removing individual elements from
the commit path.
2) We have to uninit() the data part of the element from the abort
path to avoid a chain refcount leak.
3) We have to check for set->flags to see if there's a mapping, instead
of the element flags.
4) We have to check for !(flags & NFT_SET_ELEM_INTERVAL_END) to skip
elements that are part of the interval that have no data part, so
they don't need to be uninit().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | net/netfilter/nf_tables_api.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 05380df54474..f77f4cc8e3e9 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -3606,12 +3606,11 @@ static int nf_tables_commit(struct sk_buff *skb) &te->elem, NFT_MSG_DELSETELEM, 0); te->set->ops->get(te->set, &te->elem); - te->set->ops->remove(te->set, &te->elem); nft_data_uninit(&te->elem.key, NFT_DATA_VALUE); - if (te->elem.flags & NFT_SET_MAP) { - nft_data_uninit(&te->elem.data, - te->set->dtype); - } + if (te->set->flags & NFT_SET_MAP && + !(te->elem.flags & NFT_SET_ELEM_INTERVAL_END)) + nft_data_uninit(&te->elem.data, te->set->dtype); + te->set->ops->remove(te->set, &te->elem); nft_trans_destroy(trans); break; } @@ -3652,7 +3651,7 @@ static int nf_tables_abort(struct sk_buff *skb) { struct net *net = sock_net(skb->sk); struct nft_trans *trans, *next; - struct nft_set *set; + struct nft_trans_elem *te; list_for_each_entry_safe(trans, next, &net->nft.commit_list, list) { switch (trans->msg_type) { @@ -3713,9 +3712,13 @@ static int nf_tables_abort(struct sk_buff *skb) break; case NFT_MSG_NEWSETELEM: nft_trans_elem_set(trans)->nelems--; - set = nft_trans_elem_set(trans); - set->ops->get(set, &nft_trans_elem(trans)); - set->ops->remove(set, &nft_trans_elem(trans)); + te = (struct nft_trans_elem *)trans->data; + te->set->ops->get(te->set, &te->elem); + nft_data_uninit(&te->elem.key, NFT_DATA_VALUE); + if (te->set->flags & NFT_SET_MAP && + !(te->elem.flags & NFT_SET_ELEM_INTERVAL_END)) + nft_data_uninit(&te->elem.data, te->set->dtype); + te->set->ops->remove(te->set, &te->elem); nft_trans_destroy(trans); break; case NFT_MSG_DELSETELEM: |