HID: rmi: check that report ids exist in the report_id_hash before accessing their size
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 <aduggan@synaptics.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c
index 2c3524b..0dc2514 100644
--- a/drivers/hid/hid-rmi.c
+++ b/drivers/hid/hid-rmi.c
@@ -848,6 +848,8 @@
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 @@
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;