gpiolib: cdev: fix NULL-pointer dereferences
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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: gpiolib: cdev: fix NULL-pointer dereferences There are several places where we can crash the kernel by requesting lines, unbinding the GPIO device, then calling any of the system calls relevant to the GPIO character device's annonymous file descriptors: ioctl(), read(), poll(). While I observed it with the GPIO simulator, it will also happen for any of the GPIO devices that can be hot-unplugged - for instance any HID GPIO expander (e.g. CP2112). This affects both v1 and v2 uAPI. This fixes it partially by checking if gdev->chip is not NULL but it doesn't entirely remedy the situation as we still have a race condition in which another thread can remove the device after the check.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
4.8