[PATCH 21/49] sctp: pass a kernel pointer to sctp_setsockopt_context

[Christoph Hellwig]

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

Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 net/sctp/socket.c | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index b7bf09f86a5e7..03577684be65f 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3359,40 +3359,38 @@ static int sctp_setsockopt_adaptation_layer(struct sock 
*sk,
  * received messages from the peer and does not effect the value that is
  * saved with outbound messages.
  */
-static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
+static int sctp_setsockopt_context(struct sock *sk,
+                                  struct sctp_assoc_value *params,
                                   unsigned int optlen)
 {
        struct sctp_sock *sp = sctp_sk(sk);
-       struct sctp_assoc_value params;
        struct sctp_association *asoc;
 
        if (optlen != sizeof(struct sctp_assoc_value))
                return -EINVAL;
-       if (copy_from_user(&params, optval, optlen))
-               return -EFAULT;
 
-       asoc = sctp_id2assoc(sk, params.assoc_id);
-       if (!asoc && params.assoc_id > SCTP_ALL_ASSOC &&
+       asoc = sctp_id2assoc(sk, params->assoc_id);
+       if (!asoc && params->assoc_id > SCTP_ALL_ASSOC &&
            sctp_style(sk, UDP))
                return -EINVAL;
 
        if (asoc) {
-               asoc->default_rcv_context = params.assoc_value;
+               asoc->default_rcv_context = params->assoc_value;
 
                return 0;
        }
 
        if (sctp_style(sk, TCP))
-               params.assoc_id = SCTP_FUTURE_ASSOC;
+               params->assoc_id = SCTP_FUTURE_ASSOC;
 
-       if (params.assoc_id == SCTP_FUTURE_ASSOC ||
-           params.assoc_id == SCTP_ALL_ASSOC)
-               sp->default_rcv_context = params.assoc_value;
+       if (params->assoc_id == SCTP_FUTURE_ASSOC ||
+           params->assoc_id == SCTP_ALL_ASSOC)
+               sp->default_rcv_context = params->assoc_value;
 
-       if (params.assoc_id == SCTP_CURRENT_ASSOC ||
-           params.assoc_id == SCTP_ALL_ASSOC)
+       if (params->assoc_id == SCTP_CURRENT_ASSOC ||
+           params->assoc_id == SCTP_ALL_ASSOC)
                list_for_each_entry(asoc, &sp->ep->asocs, asocs)
-                       asoc->default_rcv_context = params.assoc_value;
+                       asoc->default_rcv_context = params->assoc_value;
 
        return 0;
 }
@@ -4697,7 +4695,7 @@ static int sctp_setsockopt(struct sock *sk, int level, 
int optname,
                retval = sctp_setsockopt_adaptation_layer(sk, kopt, optlen);
                break;
        case SCTP_CONTEXT:
-               retval = sctp_setsockopt_context(sk, optval, optlen);
+               retval = sctp_setsockopt_context(sk, kopt, optlen);
                break;
        case SCTP_FRAGMENT_INTERLEAVE:
                retval = sctp_setsockopt_fragment_interleave(sk, optval, 
optlen);
-- 
2.26.2