CVE-2023-53393

An out-of-bounds write vulnerability exists in the linux kernel, such that when mlx5_ib_get_hw_stats() is used forthe device (port_num = 0), There is a special handling in order to use the correct counters, but, port_num is being passed down the stack without any change leading to damage in system availability and integrity.

A flaw in mlx5_ib_get_hw_stats() allowed port_num=0 (device-level query) to propagate down the stack, where code paths assumed port_num >= 1, leading to a NULL-pointer dereference and kernel oops during stats collection or device registration. The fix normalizes device queries by forcing port_num=1 before accessing per-port data and removes an unused variable. Exploitation requires local, highly privileged access to the RDMA device stack (e.g., devlink/IB admin), and impact is limited to local DoS.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.