CVE-2022-49976

Summary

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

platform/x86: x86-android-tablets: Fix broken touchscreen on Chuwi Hi8 with Windows BIOS

The x86-android-tablets handling for the Chuwi Hi8 is only necessary with the Android BIOS and it is causing problems with the Windows BIOS version.

Specifically when trying to register the already present touchscreen x86_acpi_irq_helper_get() calls acpi_unregister_gsi(), this breaks the working of the touchscreen and also leads to an oops:

[ 14.248946] ————[ cut here ]———— [ 14.248954] remove_proc_entry: removing non-empty directory 'irq/75', leaking at least 'MSSL0001:00' [ 14.248983] WARNING: CPU: 3 PID: 440 at fs/proc/generic.c:718 remove_proc_entry … [ 14.249293] unregister_irq_proc+0xe0/0x100 [ 14.249305] free_desc+0x29/0x70 [ 14.249312] irq_free_descs+0x4b/0x80 [ 14.249320] mp_unmap_irq+0x5c/0x60 [ 14.249329] acpi_unregister_gsi_ioapic+0x2a/0x40 [ 14.249338] x86_acpi_irq_helper_get+0x4b/0x190 [x86_android_tablets] [ 14.249355] x86_android_tablet_init+0x178/0xe34 [x86_android_tablets]

Add an init callback for the Chuwi Hi8, which detects when the Windows BIOS is in use and exits with -ENODEV in that case, fixing this.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux84c2dcdd475f3f5d1d30c87404cafba4dd4b75ec < c77b724cddfb8ac1291a60e3e68937e62cbfc5e0affected
LinuxLinux84c2dcdd475f3f5d1d30c87404cafba4dd4b75ec < 2986c51540ed50ac654ffb5a772e546c02628c91affected
LinuxLinux5.17affected
LinuxLinux0 < 5.17unaffected
LinuxLinux5.19.8 <= 5.19.*unaffected
LinuxLinux6.0 <= *unaffected

Weaknesses

References