CVE-2025-21676

Published Jan 31, 2025

Last updated 7 days ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: net: fec: handle page_pool_dev_alloc_pages error The fec_enet_update_cbd function calls page_pool_dev_alloc_pages but did not handle the case when it returned NULL. There was a WARN_ON(!new_page) but it would still proceed to use the NULL pointer and then crash. This case does seem somewhat rare but when the system is under memory pressure it can happen. One case where I can duplicate this with some frequency is when writing over a smbd share to a SATA HDD attached to an imx6q. Setting /proc/sys/vm/min_free_kbytes to higher values also seems to solve the problem for my test case. But it still seems wrong that the fec driver ignores the memory allocation error and can crash. This commit handles the allocation error by dropping the current packet.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-476
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-476

Social media

Hype score
Not currently trending

  1. CVE-2025-21676 In the Linux kernel, the following vulnerability has been resolved: net https://t.co/iLsyV9eQqq

    @VulmonFeeds

    31 Jan 2025

    26 Impressions

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  2. New post from https://t.co/uXvPWJy6tj (CVE-2025-21676 | Linux Kernel up to 6.6.73/6.12.10 page_pool_dev_alloc_pages null pointer dereference) has been published on https://t.co/3gYytlAjyB

    @WolfgangSesin

    31 Jan 2025

    27 Impressions

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  3. CVE-2025-21676 In the Linux kernel, the following vulnerability has been resolved: net: fec: handle page_pool_dev_alloc_pages error The fec_enet_update_cbd function calls page_poo… https://t.co/yHaBUAgsqP

    @CVEnew

    31 Jan 2025

    300 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.