Description
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.
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.
Published:
2026-08-26
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
No advisories yet.
References
History
Wed, 26 Aug 2026 14:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-26T14:37:31.338Z
Reserved: 2026-08-26T14:34:25.768Z
Link: CVE-2026-80569
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-08-26T15:17:12.457
Modified: 2026-08-26T15:17:12.457
Link: CVE-2026-80569
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.