CVE-2026-64274Input: goodix - clamp the device-reported contact count

Official description

In the Linux kernel, the following vulnerability has been resolved: Input: goodix - clamp the device-reported contact count goodix_ts_read_input_report() copies the number of touch points reported by the device into an on-stack buffer u8 point_data[2 + GOODIX_MAX_CONTACT_SIZE * GOODIX_MAX_CONTACTS]; which is sized for at most GOODIX_MAX_CONTACTS (10) contacts. The only runtime check bounds the per-interrupt count against ts->max_touch_num, but that value is taken verbatim from a 4-bit field of the device configuration block and is never clamped: ts->max_touch_num = ts->config[MAX_CONTACTS_LOC] & 0x0f; The nibble can be 0..15, so a malfunctioning, malicious or counterfeit controller (or an attacker tampering with the I2C bus) can advertise up to 15 contacts. goodix_ts_read_input_report() then accepts a touch_num of up to 15 and the second goodix_i2c_read() writes ts->contact_size * (touch_num - 1) bytes past the one-contact header into point_data - up to 30 bytes (45 with the 9-byte report format) beyond the 92-byte buffer: a stack out-of-bounds write. Clamp max_touch_num to GOODIX_MAX_CONTACTS, the number of contacts point_data[] is sized for, when reading it from the configuration.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/e825f352ef5271255cd08cc994b0dc25648a2f38
• https://git.kernel.org/stable/c/4bfea9c3a0981c1c7fc5d1a1b27197b2de247902
• https://git.kernel.org/stable/c/98b2caef249183b572c04451365246f919707845
• https://git.kernel.org/stable/c/719d1a2c83a46be6bf81af905e4f6adb3d32dc28
• https://git.kernel.org/stable/c/46addbd13dbf4aacb71cfbca964a5e552d0f45ae
• https://git.kernel.org/stable/c/3b32303460155603d25444274856013d211d5e1f
• https://git.kernel.org/stable/c/2a67668690129953e898923260a2dd1c7c196495
• https://git.kernel.org/stable/c/5ed62a96e06be4e94b8296b7932afee550a70e04