CVE-2022-50453
Description
In the Linux kernel, the following vulnerability has been resolved: gpiolib: cdev: fix NULL-pointer dereferences There are several places where we can crash the kernel by requesting lines, unbinding the GPIO device, then calling any of the system calls relevant to the GPIO character device's annonymous file descriptors: ioctl(), read(), poll(). While I observed it with the GPIO simulator, it will also happen for any of the GPIO devices that can be hot-unplugged - for instance any HID GPIO expander (e.g. CP2112). This affects both v1 and v2 uAPI. This fixes it partially by checking if gdev->chip is not NULL but it doesn't entirely remedy the situation as we still have a race condition in which another thread can remove the device after the check.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2022-50453
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2022-50453.html
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2024:2394
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2023:6583
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 6.1.4-1 |
| debian | bullseye | fixed | 5.10.178-1 |
| debian | forky | fixed | 6.1.4-1 |
| debian | sid | fixed | 6.1.4-1 |
| debian | trixie | fixed | 6.1.4-1 |
References
Verify integrity in audit chain (admin only). AS-IS.