diff options
Diffstat (limited to 'net/core/sock.c')
| -rw-r--r-- | net/core/sock.c | 109 |
1 files changed, 108 insertions, 1 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index e110b9004147..ed2afdb9ea2d 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -187,6 +187,99 @@ static void sock_disable_timestamp(struct sock *sk) } +int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + int err = 0; + int skb_len; + + /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces + number of warnings when compiling with -W --ANK + */ + if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= + (unsigned)sk->sk_rcvbuf) { + err = -ENOMEM; + goto out; + } + + /* It would be deadlock, if sock_queue_rcv_skb is used + with socket lock! We assume that users of this + function are lock free. + */ + err = sk_filter(sk, skb, 1); + if (err) + goto out; + + skb->dev = NULL; + skb_set_owner_r(skb, sk); + + /* Cache the SKB length before we tack it onto the receive + * queue. Once it is added it no longer belongs to us and + * may be freed by other threads of control pulling packets + * from the queue. + */ + skb_len = skb->len; + + skb_queue_tail(&sk->sk_receive_queue, skb); + + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk, skb_len); +out: + return err; +} +EXPORT_SYMBOL(sock_queue_rcv_skb); + +int sk_receive_skb(struct sock *sk, struct sk_buff *skb) +{ + int rc = NET_RX_SUCCESS; + + if (sk_filter(sk, skb, 0)) + goto discard_and_relse; + + skb->dev = NULL; + + bh_lock_sock(sk); + if (!sock_owned_by_user(sk)) + rc = sk->sk_backlog_rcv(sk, skb); + else + sk_add_backlog(sk, skb); + bh_unlock_sock(sk); +out: + sock_put(sk); + return rc; +discard_and_relse: + kfree_skb(skb); + goto out; +} +EXPORT_SYMBOL(sk_receive_skb); + +struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) +{ + struct dst_entry *dst = sk->sk_dst_cache; + + if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { + sk->sk_dst_cache = NULL; + dst_release(dst); + return NULL; + } + + return dst; +} +EXPORT_SYMBOL(__sk_dst_check); + +struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) +{ + struct dst_entry *dst = sk_dst_get(sk); + + if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { + sk_dst_reset(sk); + dst_release(dst); + return NULL; + } + + return dst; +} +EXPORT_SYMBOL(sk_dst_check); + /* * This is meant for all protocols to use and covers goings on * at the socket level. Everything here is generic. @@ -292,7 +385,21 @@ set_sndbuf: val = sysctl_rmem_max; set_rcvbuf: sk->sk_userlocks |= SOCK_RCVBUF_LOCK; - /* FIXME: is this lower bound the right one? */ + /* + * We double it on the way in to account for + * "struct sk_buff" etc. overhead. Applications + * assume that the SO_RCVBUF setting they make will + * allow that much actual data to be received on that + * socket. + * + * Applications are unaware that "struct sk_buff" and + * other overheads allocate from the receive buffer + * during socket buffer allocation. + * + * And after considering the possible alternatives, + * returning the value we actually used in getsockopt + * is the most desirable behavior. + */ if ((val * 2) < SOCK_MIN_RCVBUF) sk->sk_rcvbuf = SOCK_MIN_RCVBUF; else |