Bug 2507143 (CVE-2026-64274)

Summary: CVE-2026-64274 kernel: Input: goodix - clamp the device-reported contact count
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's Goodix touchscreen driver. An attacker with physical access to the I2C bus, or a malicious touchscreen controller, could exploit a vulnerability where the driver fails to properly validate the number of reported touch points. This could lead to a stack out-of-bounds write, potentially causing a system crash (denial of service).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-07-25 10:07:17 UTC
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.