CVE-2026-31644

HIGH

net: lan966x: fix use-after-free and leak in lan966x_fdma_reload()

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: net: lan966x: fix use-after-free and leak in lan966x_fdma_reload() When lan966x_fdma_reload() fails to allocate new RX buffers, the restore path restarts DMA using old descriptors whose pages were already freed via lan966x_fdma_rx_free_pages(). Since page_pool_put_full_page() can release pages back to the buddy allocator, the hardware may DMA into memory now owned by other kernel subsystems. Additionally, on the restore path, the newly created page pool (if allocation partially succeeded) is overwritten without being destroyed, leaking it. Fix both issues by deferring the release of old pages until after the new allocation succeeds. Save the old page array before the allocation so old pages can be freed on the success path. On the failure path, the old descriptors, pages and page pool are all still valid, making the restore safe. Also ensure the restore path re-enables NAPI and wakes the netdev, matching the success path.

Scores

CVSS v3 7.8
EPSS 0.0001
EPSS Percentile 2.4%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-416
Status published
Products (13)
Linux/Linux < 6.12
Linux/Linux 6.12
Linux/Linux 6.12.82 - 6.12.*
Linux/Linux 6.18.23 - 6.18.*
Linux/Linux 6.19.13 - 6.19.*
Linux/Linux 7.0
Linux/Linux 89ba464fcf548d64bc7215dfe769f791330ae8b6 - 59c3d55a946cacdb4181600723c20ac4f4c20c84
Linux/Linux 89ba464fcf548d64bc7215dfe769f791330ae8b6 - 691082c0b93c13a5e068c0905f673060bddc204e
Linux/Linux 89ba464fcf548d64bc7215dfe769f791330ae8b6 - 92a673019943770930e2a8bfd52e1aad47a1fc1f
Linux/Linux 89ba464fcf548d64bc7215dfe769f791330ae8b6 - 9950e9199b3dfdfbde0b8d96ba947d7b11243801
... and 3 more
Published Apr 24, 2026
Tracked Since Apr 24, 2026