tick/nohz: unexport __init-annotated tick_nohz_full_setup()
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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: tick/nohz: unexport __init-annotated tick_nohz_full_setup() 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 had been broken for a decade. Commit 28438794aba4 ("modpost: fix section mismatch check for exported init/exit sections") fixed it so modpost started to warn it again, then this showed up: MODPOST vmlinux.symvers WARNING: modpost: vmlinux.o(___ksymtab_gpl+tick_nohz_full_setup+0x0): Section mismatch in reference from the variable __ksymtab_tick_nohz_full_setup to the function .init.text:tick_nohz_full_setup() The symbol tick_nohz_full_setup is exported and annotated __init Fix this by removing the __init annotation of tick_nohz_full_setup or drop the export. Drop the export because tick_nohz_full_setup() is only called from the built-in code in kernel/sched/isolation.c.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
5.5