diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 4b5f7c8fecd1..881a5b290946 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -433,10 +433,12 @@ static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb) static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb, u32 off, u32 len, bool ingress) { - if (ingress) - return sk_psock_skb_ingress(psock, skb); - else + if (!ingress) { + if (!sock_writeable(psock->sk)) + return -EAGAIN; return skb_send_sock_locked(psock->sk, skb, off, len); + } + return sk_psock_skb_ingress(psock, skb); } static void sk_psock_backlog(struct work_struct *work) @@ -682,19 +684,8 @@ EXPORT_SYMBOL_GPL(sk_psock_msg_verdict); static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog, struct sk_buff *skb) { - int ret; - - skb->sk = psock->sk; bpf_compute_data_end_sk_skb(skb); - ret = bpf_prog_run_pin_on_cpu(prog, skb); - /* strparser clones the skb before handing it to a upper layer, - * meaning skb_orphan has been called. We NULL sk on the way out - * to ensure we don't trigger a BUG_ON() in skb/sk operations - * later and because we are not charging the memory of this skb - * to any socket yet. - */ - skb->sk = NULL; - return ret; + return bpf_prog_run_pin_on_cpu(prog, skb); } static struct sk_psock *sk_psock_from_strp(struct strparser *strp) @@ -709,38 +700,35 @@ static void sk_psock_skb_redirect(struct sk_buff *skb) { struct sk_psock *psock_other; struct sock *sk_other; - bool ingress; sk_other = tcp_skb_bpf_redirect_fetch(skb); + /* This error is a buggy BPF program, it returned a redirect + * return code, but then didn't set a redirect interface. + */ if (unlikely(!sk_other)) { kfree_skb(skb); return; } psock_other = sk_psock(sk_other); + /* This error indicates the socket is being torn down or had another + * error that caused the pipe to break. We can't send a packet on + * a socket that is in this state so we drop the skb. + */ if (!psock_other || sock_flag(sk_other, SOCK_DEAD) || !sk_psock_test_state(psock_other, SK_PSOCK_TX_ENABLED)) { kfree_skb(skb); return; } - ingress = tcp_skb_bpf_ingress(skb); - if ((!ingress && sock_writeable(sk_other)) || - (ingress && - atomic_read(&sk_other->sk_rmem_alloc) <= - sk_other->sk_rcvbuf)) { - if (!ingress) - skb_set_owner_w(skb, sk_other); - skb_queue_tail(&psock_other->ingress_skb, skb); - schedule_work(&psock_other->work); - } else { - kfree_skb(skb); - } + skb_queue_tail(&psock_other->ingress_skb, skb); + schedule_work(&psock_other->work); } -static void sk_psock_tls_verdict_apply(struct sk_buff *skb, int verdict) +static void sk_psock_tls_verdict_apply(struct sk_buff *skb, struct sock *sk, int verdict) { switch (verdict) { case __SK_REDIRECT: + skb_set_owner_r(skb, sk); sk_psock_skb_redirect(skb); break; case __SK_PASS: @@ -758,11 +746,17 @@ int sk_psock_tls_strp_read(struct sk_psock *psock, struct sk_buff *skb) rcu_read_lock(); prog = READ_ONCE(psock->progs.skb_verdict); if (likely(prog)) { + /* We skip full set_owner_r here because if we do a SK_PASS + * or SK_DROP we can skip skb memory accounting and use the + * TLS context. + */ + skb->sk = psock->sk; tcp_skb_bpf_redirect_clear(skb); ret = sk_psock_bpf_run(psock, prog, skb); ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb)); + skb->sk = NULL; } - sk_psock_tls_verdict_apply(skb, ret); + sk_psock_tls_verdict_apply(skb, psock->sk, ret); rcu_read_unlock(); return ret; } @@ -771,7 +765,9 @@ EXPORT_SYMBOL_GPL(sk_psock_tls_strp_read); static void sk_psock_verdict_apply(struct sk_psock *psock, struct sk_buff *skb, int verdict) { + struct tcp_skb_cb *tcp; struct sock *sk_other; + int err = -EIO; switch (verdict) { case __SK_PASS: @@ -780,16 +776,24 @@ static void sk_psock_verdict_apply(struct sk_psock *psock, !sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) { goto out_free; } - if (atomic_read(&sk_other->sk_rmem_alloc) <= - sk_other->sk_rcvbuf) { - struct tcp_skb_cb *tcp = TCP_SKB_CB(skb); - tcp->bpf.flags |= BPF_F_INGRESS; + tcp = TCP_SKB_CB(skb); + tcp->bpf.flags |= BPF_F_INGRESS; + + /* If the queue is empty then we can submit directly + * into the msg queue. If its not empty we have to + * queue work otherwise we may get OOO data. Otherwise, + * if sk_psock_skb_ingress errors will be handled by + * retrying later from workqueue. + */ + if (skb_queue_empty(&psock->ingress_skb)) { + err = sk_psock_skb_ingress(psock, skb); + } + if (err < 0) { skb_queue_tail(&psock->ingress_skb, skb); schedule_work(&psock->work); - break; } - goto out_free; + break; case __SK_REDIRECT: sk_psock_skb_redirect(skb); break; @@ -814,9 +818,9 @@ static void sk_psock_strp_read(struct strparser *strp, struct sk_buff *skb) kfree_skb(skb); goto out; } + skb_set_owner_r(skb, sk); prog = READ_ONCE(psock->progs.skb_verdict); if (likely(prog)) { - skb_orphan(skb); tcp_skb_bpf_redirect_clear(skb); ret = sk_psock_bpf_run(psock, prog, skb); ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb)); @@ -839,8 +843,11 @@ static int sk_psock_strp_parse(struct strparser *strp, struct sk_buff *skb) rcu_read_lock(); prog = READ_ONCE(psock->progs.skb_parser); - if (likely(prog)) + if (likely(prog)) { + skb->sk = psock->sk; ret = sk_psock_bpf_run(psock, prog, skb); + skb->sk = NULL; + } rcu_read_unlock(); return ret; }