ghsa-mpc4-rxjp-4rpf
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
vsock: fix lock inversion in vsock_assign_transport()
Syzbot reported a potential lock inversion deadlock between vsock_register_mutex and sk_lock-AF_VSOCK when vsock_linger() is called.
The issue was introduced by commit 687aa0c5581b ("vsock: Fix transport_* TOCTOU") which added vsock_register_mutex locking in vsock_assign_transport() around the transport->release() call, that can call vsock_linger(). vsock_assign_transport() can be called with sk_lock held. vsock_linger() calls sk_wait_event() that temporarily releases and re-acquires sk_lock. During this window, if another thread hold vsock_register_mutex while trying to acquire sk_lock, a circular dependency is created.
Fix this by releasing vsock_register_mutex before calling transport->release() and vsock_deassign_transport(). This is safe because we don't need to hold vsock_register_mutex while releasing the old transport, and we ensure the new transport won't disappear by obtaining a module reference first via try_module_get().
{
"affected": [],
"aliases": [
"CVE-2025-40231"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-04T16:16:15Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock: fix lock inversion in vsock_assign_transport()\n\nSyzbot reported a potential lock inversion deadlock between\nvsock_register_mutex and sk_lock-AF_VSOCK when vsock_linger() is called.\n\nThe issue was introduced by commit 687aa0c5581b (\"vsock: Fix\ntransport_* TOCTOU\") which added vsock_register_mutex locking in\nvsock_assign_transport() around the transport-\u003erelease() call, that can\ncall vsock_linger(). vsock_assign_transport() can be called with sk_lock\nheld. vsock_linger() calls sk_wait_event() that temporarily releases and\nre-acquires sk_lock. During this window, if another thread hold\nvsock_register_mutex while trying to acquire sk_lock, a circular\ndependency is created.\n\nFix this by releasing vsock_register_mutex before calling\ntransport-\u003erelease() and vsock_deassign_transport(). This is safe\nbecause we don\u0027t need to hold vsock_register_mutex while releasing the\nold transport, and we ensure the new transport won\u0027t disappear by\nobtaining a module reference first via try_module_get().",
"id": "GHSA-mpc4-rxjp-4rpf",
"modified": "2025-12-04T18:30:52Z",
"published": "2025-12-04T18:30:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40231"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/09bba278ccde25a14b6e5088a9e65a8717d0cccf"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/251caee792a21eb0b781aab91362b422c945e162"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/42ed0784d11adebf748711e503af0eb9f1e6d81d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a2a4346eea8b4cb75037dbcb20b98cb454324f80"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b44182c116778feaa05da52a426aeb9da1878dcf"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ce4f856c64f0bc30e29302a0ce41f4295ca391c5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f7c877e7535260cc7a21484c994e8ce7e8cb6780"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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