w1 - fix fops in w1_bus_notify

Introduce a check to make sure that fops are only called if they have
been defined by the slave module.

Without this check modules like w1_smem cause a NULL pointer dereference
bug.

Signed-off by: Hans-Frieder Vogt <hfvogt@gmx.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: stable <stable@vger.kernel.org> # 3.11+

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hans-Frieder Vogt 2013-10-06 21:13:35 +02:00 committed by Greg Kroah-Hartman
parent 15c03dd485
commit 2962aecef2

View file

@ -613,6 +613,9 @@ static int w1_bus_notify(struct notifier_block *nb, unsigned long action,
sl = dev_to_w1_slave(dev);
fops = sl->family->fops;
if (!fops)
return 0;
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
/* if the family driver needs to initialize something... */