CVE-2024-50020 ice: Fix improper handling of refcount in ice_sriov_set_msix_vec_count()
A reference count leak in the Intel ice network driver can lead to resource exhaustion and 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-2024-50020?
CVE-2024-50020 is a medium-severity memory corruption 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:
ice: Fix improper handling of refcount in ice_sriov_set_msix_vec_count()
This patch addresses an issue with improper reference count handling in the ice_sriov_set_msix_vec_count() function.
First, the function calls ice_get_vf_by_id(), which increments the reference count of the vf pointer. If the subsequent call to ice_get_vf_vsi() fails, the function currently returns an error without decrementing the reference count of the vf pointer, leading to a reference count leak. The correct behavior, as implemented in this patch, is to decrement the reference count using ice_put_vf(vf) before returning an error when vsi is NULL.
Second, the function calls ice_sriov_get_irqs(), which sets vf->first_vector_idx. If this call returns a negative value, indicating an error, the function returns an error without decrementing the reference count of the vf pointer, resulting in another reference count leak. The patch addresses this by adding a call to ice_put_vf(vf) before returning an error when vf->first_vector_idx < 0.
This bug was identified by an experimental static analysis tool developed by our team. The tool specializes in analyzing reference count operations and identifying potential mismanagement of reference counts. In this case, the tool flagged the missing decrement operation as a potential issue, leading to this patch.
Which versions are affected by CVE-2024-50020?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-50020?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2024-50020 being exploited?
There is no known exploitation of CVE-2024-50020 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-50020, DEBIAN-CVE-2024-50020, GHSA-2mfj-xm96-46wm, UBUNTU-CVE-2024-50020.