[PATCH 42/49] sctp: pass a kernel pointer to sctp_setsockopt_scheduler_value

[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 | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 122e6b95a8f0d..4d61c2885f8f2 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -4154,38 +4154,32 @@ static int sctp_setsockopt_scheduler(struct sock *sk,
 }
 
 static int sctp_setsockopt_scheduler_value(struct sock *sk,
-                                          char __user *optval,
+                                          struct sctp_stream_value *params,
                                           unsigned int optlen)
 {
-       struct sctp_stream_value params;
        struct sctp_association *asoc;
        int retval = -EINVAL;
 
-       if (optlen < sizeof(params))
-               goto out;
-
-       optlen = sizeof(params);
-       if (copy_from_user(&params, optval, optlen)) {
-               retval = -EFAULT;
+       if (optlen < sizeof(*params))
                goto out;
-       }
 
-       asoc = sctp_id2assoc(sk, params.assoc_id);
-       if (!asoc && params.assoc_id != SCTP_CURRENT_ASSOC &&
+       asoc = sctp_id2assoc(sk, params->assoc_id);
+       if (!asoc && params->assoc_id != SCTP_CURRENT_ASSOC &&
            sctp_style(sk, UDP))
                goto out;
 
        if (asoc) {
-               retval = sctp_sched_set_value(asoc, params.stream_id,
-                                             params.stream_value, GFP_KERNEL);
+               retval = sctp_sched_set_value(asoc, params->stream_id,
+                                             params->stream_value, GFP_KERNEL);
                goto out;
        }
 
        retval = 0;
 
        list_for_each_entry(asoc, &sctp_sk(sk)->ep->asocs, asocs) {
-               int ret = sctp_sched_set_value(asoc, params.stream_id,
-                                              params.stream_value, GFP_KERNEL);
+               int ret = sctp_sched_set_value(asoc, params->stream_id,
+                                              params->stream_value,
+                                              GFP_KERNEL);
                if (ret && !retval) /* try to return the 1st error. */
                        retval = ret;
        }
@@ -4654,7 +4648,7 @@ static int sctp_setsockopt(struct sock *sk, int level, 
int optname,
                retval = sctp_setsockopt_scheduler(sk, kopt, optlen);
                break;
        case SCTP_STREAM_SCHEDULER_VALUE:
-               retval = sctp_setsockopt_scheduler_value(sk, optval, optlen);
+               retval = sctp_setsockopt_scheduler_value(sk, kopt, optlen);
                break;
        case SCTP_INTERLEAVING_SUPPORTED:
                retval = sctp_setsockopt_interleaving_supported(sk, optval,
-- 
2.26.2