CVE-2025-39810

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

bnxt_en: Fix memory corruption when FW resources change during ifdown

bnxt_set_dflt_rings() assumes that it is always called before any TC has

been created. So it doesn't take bp->num_tc into account and assumes

that it is always 0 or 1.

In the FW resource or capability change scenario, the FW will return

flags in bnxt_hwrm_if_change() that will cause the driver to

reinitialize and call bnxt_cancel_reservations(). This will lead to

bnxt_init_dflt_ring_mode() calling bnxt_set_dflt_rings() and bp->num_tc

may be greater than 1. This will cause bp->tx_ring[] to be sized too

small and cause memory corruption in bnxt_alloc_cp_rings().

Fix it by properly scaling the TX rings by bp->num_tc in the code

paths mentioned above. Add 2 helper functions to determine

bp->tx_nr_rings and bp->tx_nr_rings_per_tc.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References