/** * sk_filter - run a packet through a socket filter * @sk: sock associated with &sk_buff * @skb: buffer to filter * * Run the filter code and then cut skb->data to correct size returned by * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller * than pkt_len we keep whole skb->data. This is the socket level * wrapper to sk_run_filter. It returns 0 if the packet should * be accepted or -EPERM if the packet should be tossed. * */ int sk_filter(struct sock *sk, struct sk_buff *skb) { int err; struct sk_filter *filter; /* * If the skb was allocated from pfmemalloc reserves, only * allow SOCK_MEMALLOC sockets to use it as this socket is * helping free memory */ if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) return -ENOMEM; err = security_sock_rcv_skb(sk, skb); if (err) return err; rcu_read_lock(); filter = rcu_dereference(sk->sk_filter); if (filter) { unsigned int pkt_len = SK_RUN_FILTER(filter, skb); err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM; } rcu_read_unlock(); return err; }
/** * sk_filter - run a packet through a socket filter * @sk: sock associated with &sk_buff * @skb: buffer to filter * * Run the filter code and then cut skb->data to correct size returned by * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller * than pkt_len we keep whole skb->data. This is the socket level * wrapper to sk_run_filter. It returns 0 if the packet should * be accepted or -EPERM if the packet should be tossed. * */ int sk_filter(struct sock *sk, struct sk_buff *skb) { int err; struct sk_filter *filter; err = security_sock_rcv_skb(sk, skb); if (err) return err; rcu_read_lock_bh(); filter = rcu_dereference_bh(sk->sk_filter); if (filter) { unsigned int pkt_len = SK_RUN_FILTER(filter, skb); err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM; } rcu_read_unlock_bh(); return err; }
/** * sk_filter - run a packet through a socket filter * @sk: sock associated with &sk_buff * @skb: buffer to filter * * Run the filter code and then cut skb->data to correct size returned by * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller * than pkt_len we keep whole skb->data. This is the socket level * wrapper to sk_run_filter. It returns 0 if the packet should * be accepted or -EPERM if the packet should be tossed. * */ int sk_filter(struct sock *sk, struct sk_buff *skb) { int err; struct sk_filter *filter; err = security_sock_rcv_skb(sk, skb); if (err) return err; err = provenance_sock_rcv_skb(sk, skb); if (err) return err; rcu_read_lock_bh(); filter = rcu_dereference(sk->sk_filter); if (filter) { unsigned int pkt_len = sk_run_filter(skb, filter->insns, filter->len); err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM; } rcu_read_unlock_bh(); return err; }