[PATCH 43/49] sctp: pass a kernel pointer to sctp_setsockopt_interleaving_supported

[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 | 34 ++++++++++------------------------
 1 file changed, 10 insertions(+), 24 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 4d61c2885f8f2..48229ffabbaee 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -4189,39 +4189,25 @@ static int sctp_setsockopt_scheduler_value(struct sock 
*sk,
 }
 
 static int sctp_setsockopt_interleaving_supported(struct sock *sk,
-                                                 char __user *optval,
+                                                 struct sctp_assoc_value *p,
                                                  unsigned int optlen)
 {
        struct sctp_sock *sp = sctp_sk(sk);
-       struct sctp_assoc_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;
-               goto out;
-       }
+       if (optlen < sizeof(*p))
+               return -EINVAL;
 
-       asoc = sctp_id2assoc(sk, params.assoc_id);
-       if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
-           sctp_style(sk, UDP))
-               goto out;
+       asoc = sctp_id2assoc(sk, p->assoc_id);
+       if (!asoc && p->assoc_id != SCTP_FUTURE_ASSOC && sctp_style(sk, UDP))
+               return -EINVAL;
 
        if (!sock_net(sk)->sctp.intl_enable || !sp->frag_interleave) {
-               retval = -EPERM;
-               goto out;
+               return -EPERM;
        }
 
-       sp->ep->intl_enable = !!params.assoc_value;
-
-       retval = 0;
-
-out:
-       return retval;
+       sp->ep->intl_enable = !!p->assoc_value;
+       return 0;
 }
 
 static int sctp_setsockopt_reuse_port(struct sock *sk, char __user *optval,
@@ -4651,7 +4637,7 @@ static int sctp_setsockopt(struct sock *sk, int level, 
int optname,
                retval = sctp_setsockopt_scheduler_value(sk, kopt, optlen);
                break;
        case SCTP_INTERLEAVING_SUPPORTED:
-               retval = sctp_setsockopt_interleaving_supported(sk, optval,
+               retval = sctp_setsockopt_interleaving_supported(sk, kopt,
                                                                optlen);
                break;
        case SCTP_REUSE_PORT:
-- 
2.26.2