From be00988cce4ed44db1e61231d0ab71a64bab44cd Mon Sep 17 00:00:00 2001 From: Jiancheng Huang Date: Fri, 24 Jul 2026 20:19:17 +0800 Subject: [PATCH] HID: lg4ff: validate report length before fixed offsets lg4ff_raw_event() rewrites fixed report offsets when combined pedals are enabled. It currently assumes that each product report contains every source and destination byte used by the rewrite. Return without rewriting a short report before each product-specific access. Apply the same bound to the computed offset path. Fixes: c832f86effbc ("HID: hid-logitech: Add combined pedal support Logitech wheels") Signed-off-by: Jiancheng Huang Assisted-by: Codex:gpt-5.6-luna Signed-off-by: Jiri Kosina --- drivers/hid/hid-lg4ff.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/hid/hid-lg4ff.c b/drivers/hid/hid-lg4ff.c index e901fdb7d033..62f99a93210c 100644 --- a/drivers/hid/hid-lg4ff.c +++ b/drivers/hid/hid-lg4ff.c @@ -336,6 +336,8 @@ int lg4ff_raw_event(struct hid_device *hdev, struct hid_report *report, if (entry->wdata.combine) { switch (entry->wdata.product_id) { case USB_DEVICE_ID_LOGITECH_WHEEL: + if (size < 7) + return 0; rd[5] = rd[3]; rd[6] = 0x7F; return 1; @@ -343,10 +345,14 @@ int lg4ff_raw_event(struct hid_device *hdev, struct hid_report *report, case USB_DEVICE_ID_LOGITECH_WINGMAN_FFG: case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL: case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2: + if (size < 6) + return 0; rd[4] = rd[3]; rd[5] = 0x7F; return 1; case USB_DEVICE_ID_LOGITECH_DFP_WHEEL: + if (size < 7) + return 0; rd[5] = rd[4]; rd[6] = 0x7F; return 1; @@ -366,6 +372,8 @@ int lg4ff_raw_event(struct hid_device *hdev, struct hid_report *report, } /* Compute a combined axis when wheel does not supply it */ + if (size <= offset + 1) + return 0; rd[offset] = (0xFF + rd[offset] - rd[offset+1]) >> 1; rd[offset+1] = 0x7F; return 1;