From 8725aa4fa7ded30211ebd28bb1c9bae806eb3841 Mon Sep 17 00:00:00 2001 From: Andrew Duggan Date: Wed, 23 Oct 2019 01:24:03 +0000 Subject: [PATCH] HID: rmi: Check that the RMI_STARTED bit is set before unregistering the RMI transport device In the event that the RMI device is unreachable, the calls to rmi_set_mode() or rmi_set_page() will fail before registering the RMI transport device. When the device is removed, rmi_remove() will call rmi_unregister_transport_device() which will attempt to access the rmi_dev pointer which was not set. This patch adds a check of the RMI_STARTED bit before calling rmi_unregister_transport_device(). The RMI_STARTED bit is only set after rmi_register_transport_device() completes successfully. The kernel oops was reported in this message: https://www.spinics.net/lists/linux-input/msg58433.html [jkosina@suse.cz: reworded changelog as agreed with Andrew] Signed-off-by: Andrew Duggan Reported-by: Federico Cerutti Signed-off-by: Jiri Kosina --- drivers/hid/hid-rmi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c index 7c6abd7..9ce22ac 100644 --- a/drivers/hid/hid-rmi.c +++ b/drivers/hid/hid-rmi.c @@ -744,7 +744,8 @@ static void rmi_remove(struct hid_device *hdev) { struct rmi_data *hdata = hid_get_drvdata(hdev); - if (hdata->device_flags & RMI_DEVICE) { + if ((hdata->device_flags & RMI_DEVICE) + && test_bit(RMI_STARTED, &hdata->flags)) { clear_bit(RMI_STARTED, &hdata->flags); cancel_work_sync(&hdata->reset_work); rmi_unregister_transport_device(&hdata->xport); -- 2.7.4