CVE-2026-31644
net: lan966x: fix use-after-free and leak in lan966x_fdma_reload()
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.
INFO
Published Date :
April 24, 2026, 3:16 p.m.
Last Modified :
April 27, 2026, 8:19 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Defer releasing old pages until new allocation succeeds.
- Save old page array before allocation for safe freeing.
- Re-enable NAPI and wake netdev on restore path failure.
- Apply the provided kernel patch.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-31644.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-31644 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-31644
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-31644 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-31644 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Apr. 27, 2026
Action Type Old Value New Value Added CWE CWE-416 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.12:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.23 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 6.19.13 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.12.1 up to (excluding) 6.12.82 Added Reference Type kernel.org: https://git.kernel.org/stable/c/59c3d55a946cacdb4181600723c20ac4f4c20c84 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/691082c0b93c13a5e068c0905f673060bddc204e Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/92a673019943770930e2a8bfd52e1aad47a1fc1f Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/9950e9199b3dfdfbde0b8d96ba947d7b11243801 Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 24, 2026
Action Type Old Value New Value Added 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. Added Reference https://git.kernel.org/stable/c/59c3d55a946cacdb4181600723c20ac4f4c20c84 Added Reference https://git.kernel.org/stable/c/691082c0b93c13a5e068c0905f673060bddc204e Added Reference https://git.kernel.org/stable/c/92a673019943770930e2a8bfd52e1aad47a1fc1f Added Reference https://git.kernel.org/stable/c/9950e9199b3dfdfbde0b8d96ba947d7b11243801