/* try to charge the socket memory if there is space available
* return true on success
*/
-bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
+static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
u32 filter_size = bpf_prog_size(fp->prog->len);
/* same check as in sock_kmalloc() */
if (filter_size <= sysctl_optmem_max &&
atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
- atomic_inc(&fp->refcnt);
atomic_add(filter_size, &sk->sk_omem_alloc);
return true;
}
return false;
}
+bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
+{
+ if (!atomic_inc_not_zero(&fp->refcnt))
+ return false;
+
+ if (!__sk_filter_charge(sk, fp)) {
+ sk_filter_release(fp);
+ return false;
+ }
+ return true;
+}
+
static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
{
struct sock_filter *old_prog;
sock_reset_flag(newsk, SOCK_DONE);
skb_queue_head_init(&newsk->sk_error_queue);
- filter = rcu_dereference_protected(newsk->sk_filter, 1);
+ rcu_read_lock();
+ filter = rcu_dereference(sk->sk_filter);
if (filter != NULL)
/* though it's an empty new sock, the charging may fail
* if sysctl_optmem_max was changed between creation of
* original socket and cloning
*/
is_charged = sk_filter_charge(newsk, filter);
+ RCU_INIT_POINTER(newsk->sk_filter, filter);
+ rcu_read_unlock();
if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
/* We need to make sure that we don't uncharge the new