CVE-2026-64603platform/x86: intel-hid: Protect ACPI notify handler against recursion

Official description

In the Linux kernel, the following vulnerability has been resolved: platform/x86: intel-hid: Protect ACPI notify handler against recursion Since commit e2ffcda16290 ("ACPI: OSL: Allow Notify () handlers to run on all CPUs") ACPI notify handlers like the intel-hid notify_handler() may run on multiple CPU cores racing with themselves. On convertibles and detachables (matched by DMI chassis-type 31 and 32 in dmi_auto_add_switch[]) the SW_TABLET_MODE input device is registered lazily from notify_handler() on the first tablet-mode event, via intel_hid_switches_setup(). When two such events race on different CPUs both can pass the !priv->switches check and register the priv->switches input device twice, resulting in a duplicate sysfs entry and a subsequent NULL pointer dereference. This is the same class of bug fixed by commit e075c3b13a0a ("platform/x86: intel-vbtn: Protect ACPI notify handler against recursion") for the sibling intel-vbtn driver. Protect intel-hid notify_handler() from racing with itself with a mutex to fix this.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/a6402808e552e44e9c26a9fe8395ac11703d5800
• https://git.kernel.org/stable/c/86df6499dfd232fbc1c82c0d6eb9322ca67b8cd0
• https://git.kernel.org/stable/c/eace3b3e729d5ba11794d69acfafb58a7950217c
• https://git.kernel.org/stable/c/c085d82613d5618814b84406c8b2d64f1bc305e7