CVE-2024-56660

What it actually does

Potential dereference of an error pointer (ERR_PTR(-ENOMEM)) returned from dr_domain_add_vport_cap() when propagated to dr_ste_v0_build_src_gvmi_qpn_tag() instead of NULL.

Why it matters to the business

Kernel instability or crashes on systems using affected Mellanox network hardware, leading to downtime and potential data loss in high-availability environments.

How an attack unfolds

An attacker triggers memory allocation failure in dr_domain_add_vport_cap() so that -ENOMEM is returned; the error pointer is then passed and dereferenced in the tag-building function, causing a crash.

How to fix it

Apply the kernel patch that resolves the error-pointer handling in dr_domain_add_vport_cap(); upgrade to a fixed kernel version containing the resolution for CVE-2024-56660.

How to confirm the fix worked

Confirm the updated kernel source no longer allows ERR_PTR(-ENOMEM) to reach the dereference site; review commit logs for the fix and test vport capability addition under memory pressure.

Typical attack path

1. Trigger conditions leading to -ENOMEM in dr_domain_add_vport_cap()
2. Allow error pointer to propagate instead of NULL
3. Dereference occurs in dr_ste_v0_build_src_gvmi_qpn_tag()
4. Resulting kernel fault causes denial of service

How to detect it

Review kernel logs for oops or panic messages involving dr_ste_v0_build_src_gvmi_qpn_tag or dr_domain_add_vport_cap under memory exhaustion conditions.

What your security team should do

• Prioritize kernel updates on systems with mlx5 hardware
• Monitor for related stability issues in network drivers
• Apply patches before any future exploitation attempts