CVE-2022-50576 serial: pch: Fix PCI device refcount leak in pch_request_dma()
A missing PCI device reference count decrement in the Linux kernel serial driver can lead to resource exhaustion and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-50576?
CVE-2022-50576 is a denial of service vulnerability in Linux, published on 22 Oct 2025. 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:
serial: pch: Fix PCI device refcount leak in pch_request_dma()
As comment of pci_get_slot() says, it returns a pci_device with its refcount increased. The caller must decrement the reference count by calling pci_dev_put().
Since 'dma_dev' is only used to filter the channel in filter(), we can call pci_dev_put() before exiting from pch_request_dma(). Add the missing pci_dev_put() for the normal and error path.
Which versions are affected by CVE-2022-50576?
How do I fix CVE-2022-50576?
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-2022-50576 being exploited?
There is no known exploitation of CVE-2022-50576 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2022-50576, GHSA-jchm-w95j-v3v9, UBUNTU-CVE-2022-50576.