watchdog: pretimeout: Fix UAF in watchdog_unregister_governor()
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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: watchdog: pretimeout: Fix UAF in watchdog_unregister_governor() When a watchdog governor is unregistered, it updates existing watchdog devices that were using this governor by falling back to `default_gov`. If the governor being unregistered is currently set as `default_gov`, the `default_gov` is never cleared. This leads to 2 use-after-free issues: 1. New watchdog devices registered after this point will inherit the dangling `default_gov`. 2. Existing watchdog devices using the unregistered governor will have their `wdd->gov` reassigned to the dangling `default_gov`. Fix the UAF by clearing `default_gov` if it matches the governor being unregistered.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
4.9
References 8
git.kernel.org
- stable/c/b9ae33faa96bdec6bc60e4c5f8f53786182e4207
- stable/c/472ec1e34ff0bb26379805cae808f658cce58c35
- stable/c/7a2ee3ec6f208307eca1119a343c7b5d39c03708
- stable/c/2e47b91b9b4020fcc01def14d6b6556d66074cf4
- stable/c/0ca252720f0e38411cfec3431db9bb1aed0a412c
- stable/c/7d1658b066de30f4b23afc14814d22416a971e6e
- stable/c/7993d626983cc58fbde9607333cfd2d57725c197
- stable/c/7362ba0f9c96ac3ad6a2ca3995bd9fc9a28a8661