Bug 2524465 (CVE-2026-80569)
| Summary: | CVE-2026-80569 kernel: Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer | ||
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| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security DevOps Team <prodsec-dev> |
| Status: | NEW --- | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | CC: | rhel-process-autobot, watson-tool-maintainers |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: |
A flaw was found in the `synaptics-rmi4` driver within the Linux kernel. A malicious or malfunctioning RMI4 device can exploit this vulnerability by reporting incorrect electrode counts. This leads to the driver attempting to write data beyond the allocated memory buffer, causing memory corruption. This issue could potentially allow an attacker to impact system stability or integrity.
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
In the Linux kernel, the following vulnerability has been resolved: Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer rmi_f54_work() reads a diagnostics report from the device into f54->report_data, sizing the transfer with rmi_f54_get_report_size(): report_size = rmi_f54_get_report_size(f54); ... for (i = 0; i < report_size; i += F54_REPORT_DATA_SIZE) { int size = min(F54_REPORT_DATA_SIZE, report_size - i); ... rmi_read_block(.., f54->report_data + i, size); } report_data is allocated once at probe from F54's own electrode counts (array3_size(f54->num_tx_electrodes, f54->num_rx_electrodes, sizeof(u16))), but rmi_f54_get_report_size() computes the size from drv_data->num_*_electrodes when those are set, i.e. from the F55 function's electrode counts. Both counts come straight from device queries (F54 and F55 each report up to 255 electrodes) and nothing constrains the F55 counts to the F54 ones. A malicious or malfunctioning RMI4 device that reports larger F55 electrode counts than its F54 counts makes report_size exceed the allocation, so the read loop writes past report_data (and the V4L2 dequeue memcpy() then reads past it). On conforming hardware the F55 configured electrodes are a subset of the F54 physical electrodes, so report_size never exceeds the buffer and well-behaved devices are unaffected. Record the allocation size and reject a report that does not fit, mirroring the existing zero-size check.