sctp: pass a kernel pointer to sctp_setsockopt_default_sndinfo

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

@@ -2925,54 +2925,51 @@ static int sctp_setsockopt_default_send_param(struct sock *sk,
  * (SCTP_DEFAULT_SNDINFO)
  */
 static int sctp_setsockopt_default_sndinfo(struct sock *sk,
-					   char __user *optval,
+					   struct sctp_sndinfo *info,
 					   unsigned int optlen)
 {
 	struct sctp_sock *sp = sctp_sk(sk);
 	struct sctp_association *asoc;
-	struct sctp_sndinfo info;
 
-	if (optlen != sizeof(info))
+	if (optlen != sizeof(*info))
 		return -EINVAL;
-	if (copy_from_user(&info, optval, optlen))
-		return -EFAULT;
-	if (info.snd_flags &
+	if (info->snd_flags &
 	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
 	      SCTP_ABORT | SCTP_EOF))
 		return -EINVAL;
 
-	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
-	if (!asoc && info.snd_assoc_id > SCTP_ALL_ASSOC &&
+	asoc = sctp_id2assoc(sk, info->snd_assoc_id);
+	if (!asoc && info->snd_assoc_id > SCTP_ALL_ASSOC &&
 	    sctp_style(sk, UDP))
 		return -EINVAL;
 
 	if (asoc) {
-		asoc->default_stream = info.snd_sid;
-		asoc->default_flags = info.snd_flags;
-		asoc->default_ppid = info.snd_ppid;
-		asoc->default_context = info.snd_context;
+		asoc->default_stream = info->snd_sid;
+		asoc->default_flags = info->snd_flags;
+		asoc->default_ppid = info->snd_ppid;
+		asoc->default_context = info->snd_context;
 
 		return 0;
 	}
 
 	if (sctp_style(sk, TCP))
-		info.snd_assoc_id = SCTP_FUTURE_ASSOC;
+		info->snd_assoc_id = SCTP_FUTURE_ASSOC;
 
-	if (info.snd_assoc_id == SCTP_FUTURE_ASSOC ||
-	    info.snd_assoc_id == SCTP_ALL_ASSOC) {
-		sp->default_stream = info.snd_sid;
-		sp->default_flags = info.snd_flags;
-		sp->default_ppid = info.snd_ppid;
-		sp->default_context = info.snd_context;
+	if (info->snd_assoc_id == SCTP_FUTURE_ASSOC ||
+	    info->snd_assoc_id == SCTP_ALL_ASSOC) {
+		sp->default_stream = info->snd_sid;
+		sp->default_flags = info->snd_flags;
+		sp->default_ppid = info->snd_ppid;
+		sp->default_context = info->snd_context;
 	}
 
-	if (info.snd_assoc_id == SCTP_CURRENT_ASSOC ||
-	    info.snd_assoc_id == SCTP_ALL_ASSOC) {
+	if (info->snd_assoc_id == SCTP_CURRENT_ASSOC ||
+	    info->snd_assoc_id == SCTP_ALL_ASSOC) {
 		list_for_each_entry(asoc, &sp->ep->asocs, asocs) {
-			asoc->default_stream = info.snd_sid;
-			asoc->default_flags = info.snd_flags;
-			asoc->default_ppid = info.snd_ppid;
-			asoc->default_context = info.snd_context;
+			asoc->default_stream = info->snd_sid;
+			asoc->default_flags = info->snd_flags;
+			asoc->default_ppid = info->snd_ppid;
+			asoc->default_context = info->snd_context;
 		}
 	}
 
@@ -4695,7 +4692,7 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_setsockopt_default_send_param(sk, kopt, optlen);
 		break;
 	case SCTP_DEFAULT_SNDINFO:
-		retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
+		retval = sctp_setsockopt_default_sndinfo(sk, kopt, optlen);
 		break;
 	case SCTP_PRIMARY_ADDR:
 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);