sctp: pass a kernel pointer to sctp_setsockopt_delayed_ack

Use the kernel pointer that sctp_setsockopt has available instead of
directly handling the user pointer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 19308c3..2dfbd7f 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2751,17 +2751,14 @@ static void sctp_apply_asoc_delayed_ack(struct sctp_sack_info *params,
  */
 
 static int sctp_setsockopt_delayed_ack(struct sock *sk,
-                                      char __user *optval, unsigned int optlen)
+                                      struct sctp_sack_info *params,
+                                      unsigned int optlen)
 {
        struct sctp_sock *sp = sctp_sk(sk);
        struct sctp_association *asoc;
-       struct sctp_sack_info params;
 
        if (optlen == sizeof(struct sctp_sack_info)) {
-               if (copy_from_user(&params, optval, optlen))
-                       return -EFAULT;
-
-               if (params.sack_delay == 0 && params.sack_freq == 0)
+               if (params->sack_delay == 0 && params->sack_freq == 0)
                        return 0;
        } else if (optlen == sizeof(struct sctp_assoc_value)) {
                pr_warn_ratelimited(DEPRECATED
@@ -2769,59 +2766,57 @@ static int sctp_setsockopt_delayed_ack(struct sock *sk,
                                    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
                                    "Use struct sctp_sack_info instead\n",
                                    current->comm, task_pid_nr(current));
-               if (copy_from_user(&params, optval, optlen))
-                       return -EFAULT;
 
-               if (params.sack_delay == 0)
-                       params.sack_freq = 1;
+               if (params->sack_delay == 0)
+                       params->sack_freq = 1;
                else
-                       params.sack_freq = 0;
+                       params->sack_freq = 0;
        } else
                return -EINVAL;
 
        /* Validate value parameter. */
-       if (params.sack_delay > 500)
+       if (params->sack_delay > 500)
                return -EINVAL;
 
        /* Get association, if sack_assoc_id != SCTP_FUTURE_ASSOC and the
         * socket is a one to many style socket, and an association
         * was not found, then the id was invalid.
         */
-       asoc = sctp_id2assoc(sk, params.sack_assoc_id);
-       if (!asoc && params.sack_assoc_id > SCTP_ALL_ASSOC &&
+       asoc = sctp_id2assoc(sk, params->sack_assoc_id);
+       if (!asoc && params->sack_assoc_id > SCTP_ALL_ASSOC &&
            sctp_style(sk, UDP))
                return -EINVAL;
 
        if (asoc) {
-               sctp_apply_asoc_delayed_ack(&params, asoc);
+               sctp_apply_asoc_delayed_ack(params, asoc);
 
                return 0;
        }
 
        if (sctp_style(sk, TCP))
-               params.sack_assoc_id = SCTP_FUTURE_ASSOC;
+               params->sack_assoc_id = SCTP_FUTURE_ASSOC;
 
-       if (params.sack_assoc_id == SCTP_FUTURE_ASSOC ||
-           params.sack_assoc_id == SCTP_ALL_ASSOC) {
-               if (params.sack_delay) {
-                       sp->sackdelay = params.sack_delay;
+       if (params->sack_assoc_id == SCTP_FUTURE_ASSOC ||
+           params->sack_assoc_id == SCTP_ALL_ASSOC) {
+               if (params->sack_delay) {
+                       sp->sackdelay = params->sack_delay;
                        sp->param_flags =
                                sctp_spp_sackdelay_enable(sp->param_flags);
                }
-               if (params.sack_freq == 1) {
+               if (params->sack_freq == 1) {
                        sp->param_flags =
                                sctp_spp_sackdelay_disable(sp->param_flags);
-               } else if (params.sack_freq > 1) {
-                       sp->sackfreq = params.sack_freq;
+               } else if (params->sack_freq > 1) {
+                       sp->sackfreq = params->sack_freq;
                        sp->param_flags =
                                sctp_spp_sackdelay_enable(sp->param_flags);
                }
        }
 
-       if (params.sack_assoc_id == SCTP_CURRENT_ASSOC ||
-           params.sack_assoc_id == SCTP_ALL_ASSOC)
+       if (params->sack_assoc_id == SCTP_CURRENT_ASSOC ||
+           params->sack_assoc_id == SCTP_ALL_ASSOC)
                list_for_each_entry(asoc, &sp->ep->asocs, asocs)
-                       sctp_apply_asoc_delayed_ack(&params, asoc);
+                       sctp_apply_asoc_delayed_ack(params, asoc);
 
        return 0;
 }
@@ -4697,7 +4692,7 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
                break;
 
        case SCTP_DELAYED_SACK:
-               retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
+               retval = sctp_setsockopt_delayed_ack(sk, kopt, optlen);
                break;
        case SCTP_PARTIAL_DELIVERY_POINT:
                retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);