On Fri, Jan 20, 2017 at 01:19:14AM +0800, Xin Long wrote:
> This patch is to implement Sender-Side Procedures for the Add
> Outgoing and Incoming Streams Request Parameter described in
> rfc6525 section 5.1.5-5.1.6.
>
> It is also to add sockopt SCTP_ADD_STREAMS in rfc6525 section
> 6.3.4 for users.
>
> Signed-off-by: Xin Long <lucien....@gmail.com>
> ---
> include/net/sctp/sctp.h | 2 +
> include/uapi/linux/sctp.h | 7 ++++
> net/sctp/socket.c | 29 ++++++++++++++
> net/sctp/stream.c | 99
> +++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 137 insertions(+)
>
> diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
> index b93820f..68ee1a6 100644
> --- a/include/net/sctp/sctp.h
> +++ b/include/net/sctp/sctp.h
> @@ -199,6 +199,8 @@ int sctp_offload_init(void);
> int sctp_send_reset_streams(struct sctp_association *asoc,
> struct sctp_reset_streams *params);
> int sctp_send_reset_assoc(struct sctp_association *asoc);
> +int sctp_send_add_streams(struct sctp_association *asoc,
> + struct sctp_add_streams *params);
>
> /*
> * Module global variables
> diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
> index c0bd8c3..a91a9cc 100644
> --- a/include/uapi/linux/sctp.h
> +++ b/include/uapi/linux/sctp.h
> @@ -118,6 +118,7 @@ typedef __s32 sctp_assoc_t;
> #define SCTP_ENABLE_STREAM_RESET 118
> #define SCTP_RESET_STREAMS 119
> #define SCTP_RESET_ASSOC 120
> +#define SCTP_ADD_STREAMS 121
>
> /* PR-SCTP policies */
> #define SCTP_PR_SCTP_NONE 0x0000
> @@ -1027,4 +1028,10 @@ struct sctp_reset_streams {
> uint16_t srs_stream_list[]; /* list if srs_num_streams is not 0 */
> };
>
> +struct sctp_add_streams {
> + sctp_assoc_t sas_assoc_id;
> + uint16_t sas_instrms;
> + uint16_t sas_outstrms;
> +};
> +
> #endif /* _UAPI_SCTP_H */
> diff --git a/net/sctp/socket.c b/net/sctp/socket.c
> index 2c5c9ca..ae0a99e 100644
> --- a/net/sctp/socket.c
> +++ b/net/sctp/socket.c
> @@ -3838,6 +3838,32 @@ static int sctp_setsockopt_reset_assoc(struct sock *sk,
> return retval;
> }
>
> +static int sctp_setsockopt_add_streams(struct sock *sk,
> + char __user *optval,
> + unsigned int optlen)
> +{
you are going to need to provide some locking here or in sctp_send_add_streams.
By replacing the in/out streams pointer you run the risk of multiple callers
modifying the pointers in parallel, or in the sctp state machine reading it
while you do.
Neil
