github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-31 02:24:24 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

HID: lenovo: Fix buffer over-read and unaligned access in X12 Tab raw_event handler

Browse Source 
In lenovo_raw_event(), the X12 Tab keyboard handler reads a 4-byte
little-endian value from the raw HID report buffer but:

  1. The size guard is size >= 3, while the access reads 4 bytes.
     A malformed 3-byte report with ID 0x03 would over-read the
     buffer by one byte.

  2. Casting u8 *data directly to __le32 * can trigger unaligned
     access faults on architectures like ARM, MIPS, and SPARC,
     because HID input buffers carry no alignment guarantee.
     (e.g. uhid payloads start at offset 6 in struct uhid_event,
     giving only 2-byte alignment.)

Fix both by tightening the size check to >= 4 and replacing the
open-coded cast + le32_to_cpu() with get_unaligned_le32(), which
handles the LE-to-CPU conversion safely regardless of alignment.

Link: https://sashiko.dev/#/message/20260512044911.99B6DC2BCB0%40smtp.kernel.org
Assisted-by: CLAUDE:claude-4-sonnet
Signed-off-by: Kean <rh_king@163.com>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
This commit is contained in:
Kean 2026-05-14 20:58:38 +08:00 committed by Benjamin Tissoires
parent 07466fc91c
commit c7ee0b73c8
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/hid/hid-lenovo.c
View File

@ -30,6 +30,7 @@
#include <linux/hid.h>
#include <linux/input.h>
#include <linux/leds.h>
#include <linux/unaligned.h>
#include <linux/workqueue.h>
#include "hid-ids.h"
@ -793,8 +794,8 @@ static int lenovo_raw_event(struct hid_device *hdev,
*/
if (unlikely((hdev->product == USB_DEVICE_ID_LENOVO_X12_TAB
|| hdev->product == USB_DEVICE_ID_LENOVO_X12_TAB2)
&& size >= 3 && report->id == 0x03))
return lenovo_raw_event_TP_X12_tab(hdev, le32_to_cpu(*(__le32 *)data));
&& size >= 4 && report->id == 0x03))
return lenovo_raw_event_TP_X12_tab(hdev, get_unaligned_le32(data));
return 0;
}