It is possible that the hid-rmi driver could get loaded onto a device which does not have the expected report ids. This should not happen because it would indicate that the hid-rmi driver is not compatible with that device. However, if it does happen it should return an error from probe instead of dereferencing a null pointer.
related bug: https://bugzilla.kernel.org/show_bug.cgi?id=80091 Signed-off-by: Andrew Duggan <adug...@synaptics.com> --- Added hid_err messages as suggested by Benjamin. This fixes the null pointer dereference from bug 80091 while the next patch addresses the binding issue in hid-core. drivers/hid/hid-rmi.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c index 3221a95..260be7a 100644 --- a/drivers/hid/hid-rmi.c +++ b/drivers/hid/hid-rmi.c @@ -848,6 +848,8 @@ static int rmi_probe(struct hid_device *hdev, const struct hid_device_id *id) struct rmi_data *data = NULL; int ret; size_t alloc_size; + struct hid_report *input_report; + struct hid_report *output_report; data = devm_kzalloc(&hdev->dev, sizeof(struct rmi_data), GFP_KERNEL); if (!data) @@ -866,12 +868,26 @@ static int rmi_probe(struct hid_device *hdev, const struct hid_device_id *id) return ret; } - data->input_report_size = (hdev->report_enum[HID_INPUT_REPORT] - .report_id_hash[RMI_ATTN_REPORT_ID]->size >> 3) - + 1 /* report id */; - data->output_report_size = (hdev->report_enum[HID_OUTPUT_REPORT] - .report_id_hash[RMI_WRITE_REPORT_ID]->size >> 3) - + 1 /* report id */; + input_report = hdev->report_enum[HID_INPUT_REPORT] + .report_id_hash[RMI_ATTN_REPORT_ID]; + if (!input_report) { + hid_err(hdev, "device does not have expected input report\n"); + ret = -ENODEV; + return ret; + } + + data->input_report_size = (input_report->size >> 3) + 1 /* report id */; + + output_report = hdev->report_enum[HID_OUTPUT_REPORT] + .report_id_hash[RMI_WRITE_REPORT_ID]; + if (!output_report) { + hid_err(hdev, "device does not have expected output report\n"); + ret = -ENODEV; + return ret; + } + + data->output_report_size = (output_report->size >> 3) + + 1 /* report id */; alloc_size = data->output_report_size + data->input_report_size; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
