CVE-2026-90113 PUBLISHED

netdevsim: update queue NAPI association on queue reset

Assigner: Linux
Reserved: 11.09.2026 Published: 17.09.2026 Updated: 17.09.2026

In the Linux kernel, the following vulnerability has been resolved:

netdevsim: update queue NAPI association on queue reset

In netdevsim, receive queues (struct nsim_rq) embed their own struct napi_struct. When queue reset is performed (e.g. via queue_reset debugfs), nsim_queue_start() swaps in a newly allocated struct nsim_rq, and nsim_queue_mem_free() later deletes and frees the old one.

However, nsim_queue_start() failed to update the queue-to-NAPI mapping via netif_queue_set_napi(). As a result, dev->_rx[idx].napi continued to point to the old NAPI struct. After the old queue was freed, a subsequent queue dump via Netlink (NETDEV_CMD_QUEUE_GET) triggered a KASAN slab-use-after-free read in nla_put_napi_id() when accessing rxq->napi->napi_id.

Fix this by calling netif_queue_set_napi() in nsim_queue_start() to associate the new NAPI with the RX queue, and clear the association with netif_queue_set_napi(..., NULL) in nsim_del_napi() during teardown.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 5bc8e8dbef27b73bd7b6d1fd5108b4fd4c6d469f to b8f32b0804b4bf0cba0ee0a093e3fd74f11d7166 (excl.)
  • affected from 5bc8e8dbef27b73bd7b6d1fd5108b4fd4c6d469f to db038ac4dca0fa626199e9c297eddd8362be0550 (excl.)
  • affected from 5bc8e8dbef27b73bd7b6d1fd5108b4fd4c6d469f to 07e98a4d5e9c292eae97c9cc5ab0937384e48492 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.14 is affected
  • unaffected from 0 to 6.14 (excl.)
  • unaffected from 6.18.52 to 6.18.* (incl.)
  • unaffected from 7.2.6 to 7.2.* (incl.)
  • unaffected from 7.3-rc1 to * (incl.)

References