CVE-2022-48867 dmaengine: idxd: Prevent use after free on completion memory
A use-after-free vulnerability in the Linux kernel's idxd driver allows attackers to cause a system crash or potentially execute code during driver unload.
- 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-2022-48867?
CVE-2022-48867 is a high-severity use after free vulnerability in Linux kernel, published on 21 Aug 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:
dmaengine: idxd: Prevent use after free on completion memory
On driver unload any pending descriptors are flushed at the time the interrupt is freed: idxd_dmaengine_drv_remove() -> drv_disable_wq() -> idxd_wq_free_irq() -> idxd_flush_pending_descs().
If there are any descriptors present that need to be flushed this flow triggers a "not present" page fault as below:
BUG: unable to handle page fault for address: ff391c97c70c9040 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page
The address that triggers the fault is the address of the descriptor that was freed moments earlier via: drv_disable_wq()->idxd_wq_free_resources()
Fix the use after free by freeing the descriptors after any possible usage. This is done after idxd_wq_reset() to ensure that the memory remains accessible during possible completion writes by the device.
Weakness: CWE-416
Which versions are affected by CVE-2022-48867?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-48867?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2022-48867 being exploited?
There is no known exploitation of CVE-2022-48867 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-48867, GHSA-cfrr-p6rw-prf5, UBUNTU-CVE-2022-48867.