HID: mcp-2221: prevent UAF in delayed work

If the device is plugged/unplugged without giving time for mcp_init_work()
to complete, we might kick in the devm free code path and thus have
unavailable struct mcp_2221 while in delayed work.

Canceling the delayed_work item is enough to solve the issue, because
cancel_delayed_work_sync will prevent the work item to requeue itself.

Fixes: 960f9df7c6 ("HID: mcp2221: add ADC/DAC support via iio subsystem")
CC: stable@vger.kernel.org
Acked-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/20230215-wip-mcp2221-v2-1-109f71fd036e@redhat.com
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
This commit is contained in:
Benjamin Tissoires 2023-02-16 11:22:58 +01:00
parent 0b028189d1
commit 47e91fdfa5

View File

@ -922,6 +922,9 @@ static void mcp2221_hid_unregister(void *ptr)
/* This is needed to be sure hid_hw_stop() isn't called twice by the subsystem */
static void mcp2221_remove(struct hid_device *hdev)
{
struct mcp2221 *mcp = hid_get_drvdata(hdev);
cancel_delayed_work_sync(&mcp->init_work);
}
#if IS_REACHABLE(CONFIG_IIO)