ISDN: Use <linux/list.h> for list of phone numbers

Simplifies the code which was previously using an open coded
singly linked list.

Also, deleting a phone number during dial-out could easily oops
the kernel before this patch.

drivers/isdn/i4l/isdn_ppp.c

@@ -413,8 +413,6 @@ get_arg(void *b, void *val, int len)
 static int
 set_arg(void *b, void *val,int len)
 {
-	if(len <= 0)
-		len = sizeof(void *);
 	if (copy_to_user(b, (void *) val, len))
 		return -EFAULT;
 	return 0;
@@ -560,13 +558,18 @@ isdn_ppp_ioctl(struct inode *ino, struct file *file, unsigned int cmd, unsigned
 			return isdn_ppp_set_compressor(is, &data);
 		case PPPIOCGCALLINFO:
 			{
+				struct isdn_net_phone *phone;
 				struct pppcallinfo pci;
+				int i;
 				memset((char *) &pci,0,sizeof(struct pppcallinfo));
-				if(lp)
-				{
+				if(lp) {
 					strncpy(pci.local_num,lp->msn,63);
-					if(lp->dial) {
-						strncpy(pci.remote_num,lp->dial->num,63);
+					i = 0;
+					list_for_each_entry(phone, &lp->phone[1], list) {
+						if (i++ == lp->dial) {
+							strncpy(pci.remote_num,phone->num,63);
+							break;
+						}
 					}
 					pci.charge_units = lp->charge;
 					if(lp->outgoing)

include/linux/isdn.h

@@ -266,7 +266,7 @@ typedef struct {
 
 /* Phone-list-element */
 struct isdn_net_phone {
-	struct isdn_net_phone *next;
+	struct list_head list;
 	char num[ISDN_MSNLEN];
 };
 
@@ -334,10 +334,10 @@ typedef struct isdn_net_local_s {
   ulong                  sqfull_stamp; /* Start-Time of overload           */
   ulong                  slavedelay;   /* Dynamic bundling delaytime       */
   int                    triggercps;   /* BogoCPS needed for trigger slave */
-  struct isdn_net_phone  *phone[2];    /* List of remote-phonenumbers      */
+  struct list_head       phone[2];     /* List of remote-phonenumbers      */
 				       /* phone[0] = Incoming Numbers      */
 				       /* phone[1] = Outgoing Numbers      */
-  struct isdn_net_phone  *dial;        /* Pointer to dialed number         */
+  int                    dial;         /* # of phone number just dialed    */
   struct net_device      *master;      /* Ptr to Master device for slaves  */
   struct net_device      *slave;       /* Ptr to Slave device for masters  */
   struct isdn_net_local_s *next;       /* Ptr to next link in bundle       */