clocksource: hyper-v: unexport __init-annotated hv_init_clocksource()
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
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)
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
5.3