CVE-2026-80754: Input: synaptics-rmi4 - fix F55 transmitter electrode count typo

CVE-2026-80754: Input: synaptics-rmi4 - fix F55 transmitter electrode count typo

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

Input: synaptics-rmi4 - fix F55 transmitter electrode count typo

During F55 sensor detection, the transmitter (TX) electrode count was
incorrectly assigned the value of the receiver (RX) electrode count
due to copy-paste typos.

This incorrect value was then propagated to the driver data and used
by F54 to determine the diagnostics report size. On devices with more
RX than TX electrodes, this inflated the perceived TX count, leading
to incorrect report size calculations and potential out-of-bounds
buffer accesses.

Fix the typos by correctly assigning the TX electrode counts.

The Linux kernel CVE team has assigned CVE-2026-80754 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 5.10.266 with commit 6484e00d6778fdf2209cd75940bc3902b276457f
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 5.15.217 with commit db4e20265ebda729610ca5cf45ca9437462c3f36
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 6.1.184 with commit a6d9646e77da7cab2dff7043a8e9f75e23b836bc
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 6.6.153 with commit 0739c65e799d4a93fe573ed23255a71fcfcc5438
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 6.12.105 with commit 9759502f5cd71805923457f183ae5b9533e20c7b
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 6.18.46 with commit 9b184c8337c6e12df129399007735a7fbcbbcb7b
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 7.1.10 with commit a81cafe3c3c2f8494063385a7b0ea7ff407bf19f
	Issue introduced in 4.10 with commit 6adba43fd222ea362c36296d1a6897c2e28fdc8e and fixed in 7.2 with commit 6058f0fea10f3caf63a435677358d1b8e9325114

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-80754
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/input/rmi4/rmi_f55.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/6484e00d6778fdf2209cd75940bc3902b276457f
	https://git.kernel.org/stable/c/db4e20265ebda729610ca5cf45ca9437462c3f36
	https://git.kernel.org/stable/c/a6d9646e77da7cab2dff7043a8e9f75e23b836bc
	https://git.kernel.org/stable/c/0739c65e799d4a93fe573ed23255a71fcfcc5438
	https://git.kernel.org/stable/c/9759502f5cd71805923457f183ae5b9533e20c7b
	https://git.kernel.org/stable/c/9b184c8337c6e12df129399007735a7fbcbbcb7b
	https://git.kernel.org/stable/c/a81cafe3c3c2f8494063385a7b0ea7ff407bf19f
	https://git.kernel.org/stable/c/6058f0fea10f3caf63a435677358d1b8e9325114