Re: gigaset: memory leak in gigaset_initcshw

From: Paul Bolle
Date: Fri Feb 05 2016 - 13:36:11 EST


On vr, 2016-02-05 at 17:06 +0100, Paul Bolle wrote:
> If that would happen, then cs can be reused while the previous
> > cs->hw.ser is not freed yet. Just a guess.
>
> I'll have to ponder on that a bit, sorry.

This is from the hit-the-code-until-it-confesses department:
--- a/drivers/isdn/gigaset/ser-gigaset.c
+++ b/drivers/isdn/gigaset/ser-gigaset.c
@@ -373,13 +373,9 @@ static void gigaset_freecshw(struct cardstate *cs)

static void gigaset_device_release(struct device *dev)
{
- struct cardstate *cs = dev_get_drvdata(dev);
-
- if (!cs)
- return;
+ struct ser_cardstate *scs = dev_get_drvdata(dev);
dev_set_drvdata(dev, NULL);
- kfree(cs->hw.ser);
- cs->hw.ser = NULL;
+ kfree(scs);
}

/*
@@ -408,7 +404,7 @@ static int gigaset_initcshw(struct cardstate *cs)
cs->hw.ser = NULL;
return rc;
}
- dev_set_drvdata(&cs->hw.ser->dev.dev, cs);
+ dev_set_drvdata(&cs->hw.ser->dev.dev, scs);

tasklet_init(&cs->write_tasklet,
gigaset_modem_fill, (unsigned long) cs);

Does that make any difference?


Paul Bolle