CVE-2026-31530
type: TechArticle
description: In the Linux kernel, the following vulnerability has been resolved: cxl/port: Fix use after free of parent_port in cxl_detach_ep() cxl_detach_ep() is called during bottom-up removal when all CXL memory devices beneath a switch port have been removed. For each port in the hierarchy it locks both the port and its parent, removes the endpoint, and if the port is now empty, marks it dead and unregisters the port by calling delete_switch_port(). There are two places during this work where the parent_port may be used after freeing: First, a concurrent detach may have already processed a port by the time a second worker finds it via bus_find_device(). Without pinning parent_port, it may already be freed when we discover port->dead and attempt to unlock the parent_port. In a production kernel that's a silent memory corruption, with lock debug, it looks like this: []DEBUG_LOCKS_WARN_ON(__owner_task(owner) != get_current()) []WARNING: kernel/locking/mutex.c:949 at __mutex_unlock_slowpath+0x1
date published: 2026-04-22T14:16:53.293
license: https://creativecommons.org/publicdomain/zero/1.0/
source: https://nvd.nist.gov/vuln/detail/CVE-2026-31530
publisher: AI Analytics
source organization: NIST National Vulnerability Database
main entity: Thing
  additional type: Vulnerability
  score: 7.8
  severity: HIGH
keywords: CWE-416

AI Analytics
type: Organization