ghsa-rcjv-j3v6-r6cv
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
drm: Fix use-after-free read in drm_getunique()
There is a time-of-check-to-time-of-use error in drm_getunique() due to retrieving file_priv->master prior to locking the device's master mutex.
An example can be seen in the crash report of the use-after-free error found by Syzbot: https://syzkaller.appspot.com/bug?id=148d2f1dfac64af52ffd27b661981a540724f803
In the report, the master pointer was used after being freed. This is because another process had acquired the device's master mutex in drm_setmaster_ioctl(), then overwrote fpriv->master in drm_new_set_master(). The old value of fpriv->master was subsequently freed before the mutex was unlocked.
To fix this, we lock the device's master mutex before retrieving the pointer from from fpriv->master. This patch passes the Syzbot reproducer test.
{
"affected": [],
"aliases": [
"CVE-2021-47280"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-21T15:15:16Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm: Fix use-after-free read in drm_getunique()\n\nThere is a time-of-check-to-time-of-use error in drm_getunique() due\nto retrieving file_priv-\u003emaster prior to locking the device\u0027s master\nmutex.\n\nAn example can be seen in the crash report of the use-after-free error\nfound by Syzbot:\nhttps://syzkaller.appspot.com/bug?id=148d2f1dfac64af52ffd27b661981a540724f803\n\nIn the report, the master pointer was used after being freed. This is\nbecause another process had acquired the device\u0027s master mutex in\ndrm_setmaster_ioctl(), then overwrote fpriv-\u003emaster in\ndrm_new_set_master(). The old value of fpriv-\u003emaster was subsequently\nfreed before the mutex was unlocked.\n\nTo fix this, we lock the device\u0027s master mutex before retrieving the\npointer from from fpriv-\u003emaster. This patch passes the Syzbot\nreproducer test.",
"id": "GHSA-rcjv-j3v6-r6cv",
"modified": "2024-12-24T18:30:48Z",
"published": "2024-05-21T15:31:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47280"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/17dab9326ff263c62dab1dbac4492e2938a049e4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/491d52e0078860b33b6c14f0a7ac74ca1b603bd6"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7d233ba700ceb593905ea82b42dadb4ec8ef85e9"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b246b4c70c1250e7814f409b243000f9c0bf79a3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b436acd1cf7fac0ba987abd22955d98025c80c2b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f773f8cccac13c7e7bbd9182e7996c727742488e"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.