Before this patch, cloned expressions are released via ->destroy. This
is a problem for the new connlimit expression since the ->destroy path
drop a reference on the conntrack modules and it unregisters hooks. The
new ->destroy_clone provides context that this expression is being
released from the packet path, so it is mirroring ->clone(), where
neither module reference is dropped nor hooks need to be unregistered -
because this done from the control plane path from the ->init() path.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
include/net/netfilter/nf_tables.h | 2 ++
net/netfilter/nf_tables_api.c | 12 ++++++++++--
net/netfilter/nft_counter.c | 1 +
3 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 4d37d6d21cfb..a9980c887293 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -749,6 +749,8 @@ struct nft_expr_ops {
const struct nft_expr *expr);
void (*destroy)(const struct nft_ctx *ctx,
const struct nft_expr *expr);
+ void (*destroy_clone)(const struct nft_ctx *ctx,
+ const struct nft_expr *expr);
int (*dump)(struct sk_buff *skb,
const struct nft_expr *expr);
int (*validate)(const struct nft_ctx *ctx,
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3adb00eae039..080026ee1b62 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3907,8 +3907,16 @@ void nft_set_elem_destroy(const struct nft_set *set, void *elem,
nft_data_release(nft_set_ext_key(ext), NFT_DATA_VALUE);
if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA))
nft_data_release(nft_set_ext_data(ext), set->dtype);
- if (destroy_expr && nft_set_ext_exists(ext, NFT_SET_EXT_EXPR))
- nf_tables_expr_destroy(&ctx, nft_set_ext_expr(ext));
+ if (destroy_expr && nft_set_ext_exists(ext, NFT_SET_EXT_EXPR)) {
+ struct nft_expr *expr = nft_set_ext_expr(ext);
+
+ if (expr->ops->destroy_clone) {
+ expr->ops->destroy_clone(&ctx, expr);
+ module_put(expr->ops->type->owner);
+ } else {
+ nf_tables_expr_destroy(&ctx, expr);
+ }
+ }
if (nft_set_ext_exists(ext, NFT_SET_EXT_OBJREF))
(*nft_set_ext_obj(ext))->use--;
kfree(elem);
diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c
index e59a74d6b7d6..a61d7edfc290 100644
--- a/net/netfilter/nft_counter.c
+++ b/net/netfilter/nft_counter.c
@@ -258,6 +258,7 @@ static const struct nft_expr_ops nft_counter_ops = {
.eval = nft_counter_eval,
.init = nft_counter_init,
.destroy = nft_counter_destroy,
+ .destroy_clone = nft_counter_destroy,
.dump = nft_counter_dump,
.clone = nft_counter_clone,
};
--
2.11.0
--
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
