CVE-2023-54048

A flaw was found in the Linux kernel's Remote Direct Memory Access (RDMA) bnxt_re driver. A local user could exploit a race condition that occurs when a Queue Pair (QP) is destroyed, but completion queue (CQ) polling continues. This can lead to a kernel panic, resulting in a Denial of Service (DoS) on the system.

This vulnerability is rated as Moderate severity because it requires systems to have specific Broadcom NetXtreme-E network controllers with Remote Direct Memory Access (RDMA) capabilities enabled and in active use. Under these conditions, concurrent cleanup of queue pairs alongside completion queue processing can trigger a kernel panic, resulting in a localized denial of service without compromising data confidentiality or integrity. Typical enterprise deployments that do not use Broadcom RoCE hardware or RDMA workloads are not affected by this flaw.

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.

To mitigate this issue, prevent the bnxt_re kernel module from loading if RDMA functionality with Broadcom NetXtreme-E hardware is not required. Create a blacklist file:

echo "blacklist bnxt_re" > /etc/modprobe.d/bnxt_re.conf

After creating the file, regenerate the initramfs and reboot the system for the changes to take effect. This may impact systems relying on the bnxt_re driver for RDMA operations.