CVE-2022-49726
Description
In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, arch/x86/kernel/cpu/mshyperv.c is never compiled as modular. (CONFIG_HYPERVISOR_GUEST is boolean)
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2022-49726
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2022-49726.html
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2023:2458
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 5.18.14-1 |
| debian | bullseye | fixed | 5.10.127-1 |
| debian | forky | fixed | 5.18.14-1 |
| debian | sid | fixed | 5.18.14-1 |
| debian | trixie | fixed | 5.18.14-1 |
References
Verify integrity in audit chain (admin only). AS-IS.