1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/isdn/i4l/isdn_net.c b/drivers/isdn/i4l/isdn_net.c
index 7c5f97033b9f..de6be7181f07 100644
--- a/drivers/isdn/i4l/isdn_net.c
+++ b/drivers/isdn/i4l/isdn_net.c
@@ -292,7 +292,9 @@ isdn_net_unbind_channel(isdn_net_local * lp)
         lp->dialstate = 0;
         dev->rx_netdev[isdn_dc2minor(lp->isdn_device, lp->isdn_channel)] = NULL;
         dev->st_netdev[isdn_dc2minor(lp->isdn_device, lp->isdn_channel)] = NULL;
-        isdn_free_channel(lp->isdn_device, lp->isdn_channel, ISDN_USAGE_NET);
+        if (lp->isdn_device != -1 && lp->isdn_channel != -1)
+                isdn_free_channel(lp->isdn_device, lp->isdn_channel,
+                                  ISDN_USAGE_NET);
         lp->flags &= ~ISDN_NET_CONNECTED;
         lp->isdn_device = -1;
         lp->isdn_channel = -1;