NetSight
medium5.5

CVE-2022-49726

In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __i…

Impact

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)

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 5.3 before 5.4.200
from 5.5 before 5.10.124
from 5.11 before 5.15.49
from 5.16 before 5.18.6
Version 5.19

Weakness classification

References