GHSA-3F36-X6R9-R53H
Vulnerability from github – Published: 2025-12-04 18:30 – Updated: 2025-12-04 18:30In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix scx_enable() crash on helper kthread creation failure
A crash was observed when the sched_ext selftests runner was terminated with Ctrl+\ while test 15 was running:
NIP [c00000000028fa58] scx_enable.constprop.0+0x358/0x12b0 LR [c00000000028fa2c] scx_enable.constprop.0+0x32c/0x12b0 Call Trace: scx_enable.constprop.0+0x32c/0x12b0 (unreliable) bpf_struct_ops_link_create+0x18c/0x22c __sys_bpf+0x23f8/0x3044 sys_bpf+0x2c/0x6c system_call_exception+0x124/0x320 system_call_vectored_common+0x15c/0x2ec
kthread_run_worker() returns an ERR_PTR() on failure rather than NULL, but the current code in scx_alloc_and_add_sched() only checks for a NULL helper. Incase of failure on SIGQUIT, the error is not handled in scx_alloc_and_add_sched() and scx_enable() ends up dereferencing an error pointer.
Error handling is fixed in scx_alloc_and_add_sched() to propagate PTR_ERR() into ret, so that scx_enable() jumps to the existing error path, avoiding random dereference on failure.
{
"affected": [],
"aliases": [
"CVE-2025-40260"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-04T16:16:19Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix scx_enable() crash on helper kthread creation failure\n\nA crash was observed when the sched_ext selftests runner was\nterminated with Ctrl+\\ while test 15 was running:\n\nNIP [c00000000028fa58] scx_enable.constprop.0+0x358/0x12b0\nLR [c00000000028fa2c] scx_enable.constprop.0+0x32c/0x12b0\nCall Trace:\nscx_enable.constprop.0+0x32c/0x12b0 (unreliable)\nbpf_struct_ops_link_create+0x18c/0x22c\n__sys_bpf+0x23f8/0x3044\nsys_bpf+0x2c/0x6c\nsystem_call_exception+0x124/0x320\nsystem_call_vectored_common+0x15c/0x2ec\n\nkthread_run_worker() returns an ERR_PTR() on failure rather than NULL,\nbut the current code in scx_alloc_and_add_sched() only checks for a NULL\nhelper. Incase of failure on SIGQUIT, the error is not handled in\nscx_alloc_and_add_sched() and scx_enable() ends up dereferencing an\nerror pointer.\n\nError handling is fixed in scx_alloc_and_add_sched() to propagate\nPTR_ERR() into ret, so that scx_enable() jumps to the existing error\npath, avoiding random dereference on failure.",
"id": "GHSA-3f36-x6r9-r53h",
"modified": "2025-12-04T18:30:53Z",
"published": "2025-12-04T18:30:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40260"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/625e173e2a59b6cf6cbfb51c0a6bea47f3861eab"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7b6216baae751369195fa3c83d434d23bcda406a"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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- Confirmed: The vulnerability has been validated from an analyst's perspective.
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- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.