ghsa-mg7c-mfqw-jg72
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
md: fix mddev uaf while iterating all_mddevs list
While iterating all_mddevs list from md_notify_reboot() and md_exit(), list_for_each_entry_safe is used, and this can race with deletint the next mddev, causing UAF:
t1: spin_lock //list_for_each_entry_safe(mddev, n, ...) mddev_get(mddev1) // assume mddev2 is the next entry spin_unlock t2: //remove mddev2 ... mddev_free spin_lock list_del spin_unlock kfree(mddev2) mddev_put(mddev1) spin_lock //continue dereference mddev2->all_mddevs
The old helper for_each_mddev() actually grab the reference of mddev2 while holding the lock, to prevent from being freed. This problem can be fixed the same way, however, the code will be complex.
Hence switch to use list_for_each_entry, in this case mddev_put() can free the mddev1 and it's not safe as well. Refer to md_seq_show(), also factor out a helper mddev_put_locked() to fix this problem.
{
"affected": [],
"aliases": [
"CVE-2025-22126"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-04-16T15:16:06Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmd: fix mddev uaf while iterating all_mddevs list\n\nWhile iterating all_mddevs list from md_notify_reboot() and md_exit(),\nlist_for_each_entry_safe is used, and this can race with deletint the\nnext mddev, causing UAF:\n\nt1:\nspin_lock\n//list_for_each_entry_safe(mddev, n, ...)\n mddev_get(mddev1)\n // assume mddev2 is the next entry\n spin_unlock\n t2:\n //remove mddev2\n ...\n mddev_free\n spin_lock\n list_del\n spin_unlock\n kfree(mddev2)\n mddev_put(mddev1)\n spin_lock\n //continue dereference mddev2-\u003eall_mddevs\n\nThe old helper for_each_mddev() actually grab the reference of mddev2\nwhile holding the lock, to prevent from being freed. This problem can be\nfixed the same way, however, the code will be complex.\n\nHence switch to use list_for_each_entry, in this case mddev_put() can free\nthe mddev1 and it\u0027s not safe as well. Refer to md_seq_show(), also factor\nout a helper mddev_put_locked() to fix this problem.",
"id": "GHSA-mg7c-mfqw-jg72",
"modified": "2025-04-25T12:30:27Z",
"published": "2025-04-16T15:34:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-22126"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5462544ccbad3fc938a71b01fa5bd3a0dc2b750a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8542870237c3a48ff049b6c5df5f50c8728284fa"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ca9f84de76723b358dfc0606668efdca54afc2e5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d69a23d8e925f8052d657652a6875ec2712c7e33"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e2a9f73ee408a460f4c9dfe03b4741d6b11652b8"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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