sctp: pass a kernel pointer to sctp_setsockopt_deactivate_key

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>

net/sctp/socket.c

@@ -3750,42 +3750,40 @@ static int sctp_setsockopt_del_key(struct sock *sk,
  *
  * This set option will deactivate a shared secret key.
  */
-static int sctp_setsockopt_deactivate_key(struct sock *sk, char __user *optval,
+static int sctp_setsockopt_deactivate_key(struct sock *sk,
+					  struct sctp_authkeyid *val,
 					  unsigned int optlen)
 {
 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
 	struct sctp_association *asoc;
-	struct sctp_authkeyid val;
 	int ret = 0;
 
 	if (optlen != sizeof(struct sctp_authkeyid))
 		return -EINVAL;
-	if (copy_from_user(&val, optval, optlen))
-		return -EFAULT;
 
-	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
-	if (!asoc && val.scact_assoc_id > SCTP_ALL_ASSOC &&
+	asoc = sctp_id2assoc(sk, val->scact_assoc_id);
+	if (!asoc && val->scact_assoc_id > SCTP_ALL_ASSOC &&
 	    sctp_style(sk, UDP))
 		return -EINVAL;
 
 	if (asoc)
-		return sctp_auth_deact_key_id(ep, asoc, val.scact_keynumber);
+		return sctp_auth_deact_key_id(ep, asoc, val->scact_keynumber);
 
 	if (sctp_style(sk, TCP))
-		val.scact_assoc_id = SCTP_FUTURE_ASSOC;
+		val->scact_assoc_id = SCTP_FUTURE_ASSOC;
 
-	if (val.scact_assoc_id == SCTP_FUTURE_ASSOC ||
-	    val.scact_assoc_id == SCTP_ALL_ASSOC) {
-		ret = sctp_auth_deact_key_id(ep, asoc, val.scact_keynumber);
+	if (val->scact_assoc_id == SCTP_FUTURE_ASSOC ||
+	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
+		ret = sctp_auth_deact_key_id(ep, asoc, val->scact_keynumber);
 		if (ret)
 			return ret;
 	}
 
-	if (val.scact_assoc_id == SCTP_CURRENT_ASSOC ||
-	    val.scact_assoc_id == SCTP_ALL_ASSOC) {
+	if (val->scact_assoc_id == SCTP_CURRENT_ASSOC ||
+	    val->scact_assoc_id == SCTP_ALL_ASSOC) {
 		list_for_each_entry(asoc, &ep->asocs, asocs) {
 			int res = sctp_auth_deact_key_id(ep, asoc,
-							 val.scact_keynumber);
+							 val->scact_keynumber);
 
 			if (res && !ret)
 				ret = res;
@@ -4689,7 +4687,7 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_setsockopt_del_key(sk, kopt, optlen);
 		break;
 	case SCTP_AUTH_DEACTIVATE_KEY:
-		retval = sctp_setsockopt_deactivate_key(sk, optval, optlen);
+		retval = sctp_setsockopt_deactivate_key(sk, kopt, optlen);
 		break;
 	case SCTP_AUTO_ASCONF:
 		retval = sctp_setsockopt_auto_asconf(sk, optval, optlen);