[PATCH 20/49] sctp: pass a kernel pointer to sctp_setsockopt_adaptation_layer

[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 | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 4374d4fff080a..b7bf09f86a5e7 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3333,17 +3333,14 @@ static int sctp_setsockopt_peer_primary_addr(struct 
sock *sk,
        return err;
 }
 
-static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user 
*optval,
+static int sctp_setsockopt_adaptation_layer(struct sock *sk,
+                                           struct sctp_setadaptation *adapt,
                                            unsigned int optlen)
 {
-       struct sctp_setadaptation adaptation;
-
        if (optlen != sizeof(struct sctp_setadaptation))
                return -EINVAL;
-       if (copy_from_user(&adaptation, optval, optlen))
-               return -EFAULT;
 
-       sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
+       sctp_sk(sk)->adaptation_ind = adapt->ssb_adaptation_ind;
 
        return 0;
 }
@@ -4697,7 +4694,7 @@ static int sctp_setsockopt(struct sock *sk, int level, 
int optname,
                retval = sctp_setsockopt_maxseg(sk, kopt, optlen);
                break;
        case SCTP_ADAPTATION_LAYER:
-               retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
+               retval = sctp_setsockopt_adaptation_layer(sk, kopt, optlen);
                break;
        case SCTP_CONTEXT:
                retval = sctp_setsockopt_context(sk, optval, optlen);
-- 
2.26.2