[media] mantis: fix silly crash case

commit e1d45ae10aea8e8a403e5d96bf5902ee670007ff upstream.

If we set mantis->fe to NULL on an error its not a good idea to then try
passing NULL to the unregister paths and oopsing really.

Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=16473

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/media/dvb/mantis/mantis_dvb.c b/drivers/media/dvb/mantis/mantis_dvb.c
index e5180e4..5d15c6b 100644 (file)
--- a/drivers/media/dvb/mantis/mantis_dvb.c
+++ b/drivers/media/dvb/mantis/mantis_dvb.c
@@ -248,8 +248,10 @@ int __devinit mantis_dvb_init(struct mantis_pci *mantis)
 err5:
        tasklet_kill(&mantis->tasklet);
        dvb_net_release(&mantis->dvbnet);
-       dvb_unregister_frontend(mantis->fe);
-       dvb_frontend_detach(mantis->fe);
+       if (mantis->fe) {
+               dvb_unregister_frontend(mantis->fe);
+               dvb_frontend_detach(mantis->fe);
+       }
 err4:
        mantis->demux.dmx.remove_frontend(&mantis->demux.dmx, &mantis->fe_mem);