This patch adds support for set flushing, that consists of walking over
the set elements if the NFTA_SET_ELEM_LIST_ELEMENTS attribute is set.
This patch requires the following changes:
1) Add set->ops->deactivate_one() operation: This allows us to
deactivate an element from the set element walk path, given we can
skip the lookup that happens in ->deactivate().
2) Add a new nft_trans_alloc_gfp() function since we need to allocate
transactions using GFP_ATOMIC given the set walk path happens with
held rcu_read_lock.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
include/net/netfilter/nf_tables.h | 6 ++++-
net/netfilter/nf_tables_api.c | 55 ++++++++++++++++++++++++++++++++++-----
net/netfilter/nft_set_hash.c | 1 +
net/netfilter/nft_set_rbtree.c | 1 +
4 files changed, 56 insertions(+), 7 deletions(-)
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 32970cba184a..e3ca6fca6496 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -259,7 +259,8 @@ struct nft_expr;
* @lookup: look up an element within the set
* @insert: insert new element into set
* @activate: activate new element in the next generation
- * @deactivate: deactivate element in the next generation
+ * @deactivate: lookup for element and deactivate it in the next generation
+ * @deactivate_one: deactivate element in the next generation
* @remove: remove element from set
* @walk: iterate over all set elemeennts
* @privsize: function to return size of set private data
@@ -294,6 +295,9 @@ struct nft_set_ops {
void * (*deactivate)(const struct net *net,
const struct nft_set *set,
const struct nft_set_elem *elem);
+ bool (*deactivate_one)(const struct net *net,
+ const struct nft_set *set,
+ void *priv);
void (*remove)(const struct nft_set *set,
const struct nft_set_elem *elem);
void (*walk)(const struct nft_ctx *ctx,
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index b8fa54ec6bbb..2cfa63f6b481 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -110,12 +110,12 @@ static void nft_ctx_init(struct nft_ctx *ctx,
ctx->seq = nlh->nlmsg_seq;
}
-static struct nft_trans *nft_trans_alloc(const struct nft_ctx *ctx,
- int msg_type, u32 size)
+static struct nft_trans *nft_trans_alloc_gfp(const struct nft_ctx *ctx,
+ int msg_type, u32 size, gfp_t gfp)
{
struct nft_trans *trans;
- trans = kzalloc(sizeof(struct nft_trans) + size, GFP_KERNEL);
+ trans = kzalloc(sizeof(struct nft_trans) + size, gfp);
if (trans == NULL)
return NULL;
@@ -125,6 +125,12 @@ static struct nft_trans *nft_trans_alloc(const struct nft_ctx *ctx,
return trans;
}
+static struct nft_trans *nft_trans_alloc(const struct nft_ctx *ctx,
+ int msg_type, u32 size)
+{
+ return nft_trans_alloc_gfp(ctx, msg_type, size, GFP_KERNEL);
+}
+
static void nft_trans_destroy(struct nft_trans *trans)
{
list_del(&trans->list);
@@ -3779,6 +3785,34 @@ static int nft_del_setelem(struct nft_ctx *ctx, struct nft_set *set,
return err;
}
+static int nft_flush_set(const struct nft_ctx *ctx,
+ const struct nft_set *set,
+ const struct nft_set_iter *iter,
+ const struct nft_set_elem *elem)
+{
+ struct nft_trans *trans;
+ int err;
+
+ trans = nft_trans_alloc_gfp(ctx, NFT_MSG_DELSETELEM,
+ sizeof(struct nft_trans_elem), GFP_ATOMIC);
+ if (!trans)
+ return -ENOMEM;
+
+ if (!set->ops->deactivate_one(ctx->net, set, elem->priv)) {
+ err = -ENOENT;
+ goto err1;
+ }
+
+ nft_trans_elem_set(trans) = (struct nft_set *)set;
+ nft_trans_elem(trans) = *((struct nft_set_elem *)elem);
+ list_add_tail(&trans->list, &ctx->net->nft.commit_list);
+
+ return 0;
+err1:
+ kfree(trans);
+ return err;
+}
+
static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
struct sk_buff *skb, const struct nlmsghdr *nlh,
const struct nlattr * const nla[])
@@ -3789,9 +3823,6 @@ static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
struct nft_ctx ctx;
int rem, err = 0;
- if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL)
- return -EINVAL;
-
err = nft_ctx_init_from_elemattr(&ctx, net, skb, nlh, nla, genmask);
if (err < 0)
return err;
@@ -3803,6 +3834,18 @@ static int nf_tables_delsetelem(struct net *net, struct sock *nlsk,
if (!list_empty(&set->bindings) && set->flags & NFT_SET_CONSTANT)
return -EBUSY;
+ if (nla[NFTA_SET_ELEM_LIST_ELEMENTS] == NULL) {
+ struct nft_set_dump_args args = {
+ .iter = {
+ .genmask = genmask,
+ .fn = nft_flush_set,
+ },
+ };
+ set->ops->walk(&ctx, set, &args.iter);
+
+ return args.iter.err;
+ }
+
nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
err = nft_del_setelem(&ctx, set, attr);
if (err < 0)
diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c
index 73f7687c5656..1e20e2bbb6d9 100644
--- a/net/netfilter/nft_set_hash.c
+++ b/net/netfilter/nft_set_hash.c
@@ -397,6 +397,7 @@ static struct nft_set_ops nft_hash_ops __read_mostly = {
.insert = nft_hash_insert,
.activate = nft_hash_activate,
.deactivate = nft_hash_deactivate,
+ .deactivate_one = nft_hash_deactivate_one,
.remove = nft_hash_remove,
.lookup = nft_hash_lookup,
.update = nft_hash_update,
diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index 845bbdb26853..58d033d4de60 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -304,6 +304,7 @@ static struct nft_set_ops nft_rbtree_ops __read_mostly = {
.insert = nft_rbtree_insert,
.remove = nft_rbtree_remove,
.deactivate = nft_rbtree_deactivate,
+ .deactivate_one = nft_rbtree_deactivate_one,
.activate = nft_rbtree_activate,
.lookup = nft_rbtree_lookup,
.walk = nft_rbtree_walk,
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
