diff options
| -rw-r--r-- | net/sctp/socket.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 9f5fe23773a..b14a8f33e42 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3010,14 +3010,21 @@ static int sctp_setsockopt_fragment_interleave(struct sock *sk, } /* - * 7.1.25. Set or Get the sctp partial delivery point + * 8.1.21. Set or Get the SCTP Partial Delivery Point * (SCTP_PARTIAL_DELIVERY_POINT) + * * This option will set or get the SCTP partial delivery point. This * point is the size of a message where the partial delivery API will be * invoked to help free up rwnd space for the peer. Setting this to a - * lower value will cause partial delivery's to happen more often. The + * lower value will cause partial deliveries to happen more often. The * calls argument is an integer that sets or gets the partial delivery - * point. + * point. Note also that the call will fail if the user attempts to set + * this value larger than the socket receive buffer size. + * + * Note that any single message having a length smaller than or equal to + * the SCTP partial delivery point will be delivered in one single read + * call as long as the user provided buffer is large enough to hold the + * message. */ static int sctp_setsockopt_partial_delivery_point(struct sock *sk, char __user *optval, @@ -3030,6 +3037,12 @@ static int sctp_setsockopt_partial_delivery_point(struct sock *sk, if (get_user(val, (int __user *)optval)) return -EFAULT; + /* Note: We double the receive buffer from what the user sets + * it to be, also initial rwnd is based on rcvbuf/2. + */ + if (val > (sk->sk_rcvbuf >> 1)) + return -EINVAL; + sctp_sk(sk)->pd_point = val; return 0; /* is this the right error code? */ |