CVE-2022-50370

/// Technical description

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

i2c: designware: Fix handling of real but unexpected device interrupts

Commit c7b79a752871 ("mfd: intel-lpss: Add Intel Alder Lake PCH-S PCI

IDs") caused a regression on certain Gigabyte motherboards for Intel

Alder Lake-S where system crashes to NULL pointer dereference in

i2c_dw_xfer_msg() when system resumes from S3 sleep state ("deep").

I was able to debug the issue on Gigabyte Z690 AORUS ELITE and made

following notes:

- Issue happens when resuming from S3 but not when resuming from

"s2idle"

- PCI device 00:15.0 == i2c_designware.0 is already in D0 state when

system enters into pci_pm_resume_noirq() while all other i2c_designware

PCI devices are in D3. Devices were runtime suspended and in D3 prior

entering into suspend

- Interrupt comes after pci_pm_resume_noirq() when device interrupts are

re-enabled

- According to register dump the interrupt really comes from the

i2c_designware.0. Controller is

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References