[PATCH 6/7] HID: roccat: ryos: reject short special reports

[Jiale Yao]

The raw event callback runs before HID core validates and zero-pads the
report.  It reads the report number without checking the received length
and passes matching data to roccat_report_event(), which copies a complete
struct ryos_report_special.  A truncated report can therefore cause an
out-of-bounds read and expose adjacent data through the Roccat character
device.

Require a complete special report before inspecting or forwarding it.
Commit 47669bec44fe ("HID: asus: refactor the two workqueues and init
sequence") added the same kind of raw-event length validation to hid-asus.

Fixes: 6f3a19360545 ("HID: roccat: add support for Ryos MK keyboards")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
 drivers/hid/hid-roccat-ryos.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/hid/hid-roccat-ryos.c b/drivers/hid/hid-roccat-ryos.c
index db83f42457da..85df7955b87c 100644
--- a/drivers/hid/hid-roccat-ryos.c
+++ b/drivers/hid/hid-roccat-ryos.c
@@ -189,6 +189,9 @@ static int ryos_raw_event(struct hid_device *hdev,
 			!= RYOS_USB_INTERFACE_PROTOCOL)
 		return 0;
 
+	if (size < sizeof(struct ryos_report_special))
+		return 0;
+
 	if (data[0] != RYOS_REPORT_NUMBER_SPECIAL)
 		return 0;
 
-- 
2.34.1