mfd: wm831x-auxadc: Prevent use after free in wm831x_auxadc_read_irq()

[ Upstream commit 26783d74cc ]

The "req" struct is always added to the "wm831x->auxadc_pending" list,
but it's only removed from the list on the success path.  If a failure
occurs then the "req" struct is freed but it's still on the list,
leading to a use after free.

Fixes: 78bb3688ea ("mfd: Support multiple active WM831x AUXADC conversions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Dan Carpenter 2021-01-29 17:37:24 +03:00 committed by Greg Kroah-Hartman
parent 046a815898
commit 0c79abee60

View file

@ -93,11 +93,10 @@ static int wm831x_auxadc_read_irq(struct wm831x *wm831x,
wait_for_completion_timeout(&req->done, msecs_to_jiffies(500));
mutex_lock(&wm831x->auxadc_lock);
list_del(&req->list);
ret = req->val;
out:
list_del(&req->list);
mutex_unlock(&wm831x->auxadc_lock);
kfree(req);