CVE-2025-68209

Description

In the Linux kernel, the following vulnerability has been resolved: mlx5: Fix default values in create CQ Currently, CQs without a completion function are assigned the mlx5_add_cq_to_tasklet function by default. This is problematic since only user CQs created through the mlx5_ib driver are intended to use this function. Additionally, all CQs that will use doorbells instead of polling for completions must call mlx5_cq_arm. However, the default CQ creation flow leaves a valid value in the CQ's arm_db field, allowing FW to send interrupts to polling-only CQs in certain corner cases. These two factors would allow a polling-only kernel CQ to be triggered by an EQ interrupt and call a completion function intended only for user CQs, causing a null pointer exception. Some areas in the driver have prevented this issue with one-off fixes but did not address the root cause. This patch fixes the described issue by adding defaults to the create CQ flow. It adds a default dummy completion function to protect against null pointer exceptions, and it sets an invalid command sequence number by default in kernel CQs to prevent the FW from sending an interrupt to the CQ until it is armed. User CQs are responsible for their own initialization values. Callers of mlx5_core_create_cq are responsible for changing the completion function and arming the CQ per their needs.

Gravité et risque d'exploitation

CVE-2025-68209 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.18 %, ce qui la place devant 7.5 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa, <e5eba42f01340f73888dfe560be2806057c25913, <=*, <=6.17.*, 6.18, 6.0, 0, <6.0, 6.17.9, <08469f5393a1a39f26a6e2eb2e8c33187665c1f4) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/08469f5393a1a39f26a6e2eb2e8c33187665c1f4
• https://git.kernel.org/stable/c/e5eba42f01340f73888dfe560be2806057c25913