CVE-2022-48996 mm/damon/sysfs: fix wrong empty schemes assumption under online tuning in damon_sysfs_set_schemes()
A logic error in Linux kernel DAMON sysfs interface causes excessive memory usage during online tuning, potentially leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-48996?
CVE-2022-48996 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 Oct 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/sysfs: fix wrong empty schemes assumption under online tuning in damon_sysfs_set_schemes()
Commit da87878010e5 ("mm/damon/sysfs: support online inputs update") made 'damon_sysfs_set_schemes()' to be called for running DAMON context, which could have schemes. In the case, DAMON sysfs interface is supposed to update, remove, or add schemes to reflect the sysfs files. However, the code is assuming the DAMON context wouldn't have schemes at all, and therefore creates and adds new schemes. As a result, the code doesn't work as intended for online schemes tuning and could have more than expected memory footprint. The schemes are all in the DAMON context, so it doesn't leak the memory, though.
Remove the wrong asssumption (the DAMON context wouldn't have schemes) in 'damon_sysfs_set_schemes()' to fix the bug.
Which versions are affected by CVE-2022-48996?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-48996?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-48996 being exploited?
There is no known exploitation of CVE-2022-48996 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-48996, GHSA-gqp9-r7wj-r9hc, UBUNTU-CVE-2022-48996.