Threats Tagged 'cve-2025-40343'

A critical vulnerability in the Linux kernel's nvmet-fc subsystem involves scheduling association deletion twice during forced port shutdown via the configfs interface. The flaw arises because the system schedules deletion work items without properly preventing duplicate scheduling, potentially leading to double-free scenarios. This occurs as the association list uses RCU synchronization, preventing direct locking and removal, requiring a flag to track deletion status. The vulnerability has been resolved in the Linux kernel.

In the Linux kernel, the following vulnerability has been resolved: nvmet-fc: avoid scheduling association deletion twice When forcefully shutting down a port via the configfs interface, nvmet_port_subsys_drop_link() first calls nvmet_port_del_ctrls() and then nvmet_disable_port(). Both functions will eventually schedule all remaining associations for deletion. The current implementation checks whether an association is about to be removed, but only after the work item has already been scheduled. As a result, it is possible for the first scheduled work item to free all resources, and then for the same work item to be scheduled again for deletion. Because the association list is an RCU list, it is not possible to take a lock and remove the list entry directly, so it cannot be looked up again. Instead, a flag (terminating) must be used to determine whether the association is already in the process of being deleted.