CVE-2026-43468

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix deadlock between devlink lock and esw->wq esw->work_queue executes esw_functions_changed_event_handler -> esw_vfs_changed_event_handler and acquires the devlink lock. .eswitch_mode_set (acquires devlink lock in devlink_nl_pre_doit) -> mlx5_devlink_eswitch_mode_set -> mlx5_eswitch_disable_locked -> mlx5_eswitch_event_handler_unregister -> flush_workqueue deadlocks when esw_vfs_changed_event_handler executes. Fix that by no longer flushing the work to avoid the deadlock, and using a generation counter to keep track of work relevance. This avoids an old handler manipulating an esw that has undergone one or more mode changes: - the counter is incremented in mlx5_eswitch_event_handler_unregister. - the counter is read and passed to the ephemeral mlx5_host_work struct. - the work handler takes the devlink lock and bails out if the current generation is different than the one it was scheduled to operate on. - mlx5_eswitch_cleanup does the final draining before destroying the wq. No longer flushing the workqueue has the side effect of maybe no longer cancelling pending vport_change_handler work items, but that's ok since those are disabled elsewhere: - mlx5_eswitch_disable_locked disables the vport eq notifier. - mlx5_esw_vport_disable disarms the HW EQ notification and marks vport->enabled under state_lock to false to prevent pending vport handler from doing anything. - mlx5_eswitch_cleanup destroys the workqueue and makes sure all events are disabled/finished.

Gravité et risque d'exploitation

CVE-2026-43468 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 0.13 %, ce qui la place devant 2.0 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, 6.12.78, <90e7e5d14d0bd25ffd019a3aa39d9f1c05fedbe1, 0, f1bc646c9a06f09aad5d8bacb87103b5573ee45e, 7.0, <aed763abf0e905b4b8d747d1ba9e172961572f57, <3c7313cb41b1b427078440364d2f042c276a1c0b, 6.18.19, <=6.6.*, 6.0, <=6.19.*, <6.0, 6.19.9, <957d2a58f7f8ebcbdd0a85935e0d2675134b890d, <=6.18.*, 6.1.167, <0de867f6e34eae6907b367fd152c55e61cb98608, <4a7838bebc38374f74baaf88bf2cf8d439a92923, <=*, 6.6.130) 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/0de867f6e34eae6907b367fd152c55e61cb98608
• https://git.kernel.org/stable/c/957d2a58f7f8ebcbdd0a85935e0d2675134b890d
• https://git.kernel.org/stable/c/3c7313cb41b1b427078440364d2f042c276a1c0b
• https://git.kernel.org/stable/c/4a7838bebc38374f74baaf88bf2cf8d439a92923
• https://git.kernel.org/stable/c/90e7e5d14d0bd25ffd019a3aa39d9f1c05fedbe1
• https://git.kernel.org/stable/c/aed763abf0e905b4b8d747d1ba9e172961572f57