GHSA-5FHQ-J2H9-6QRX
Vulnerability from github – Published: 2026-09-17 18:31 – Updated: 2026-09-17 18:31In the Linux kernel, the following vulnerability has been resolved:
s390/debug: Fix deadlock during unregister
Unregistering an s390dbf debug area while one of the associated debugfs files is being written to can cause a deadlock:
$ echo >.../vmur/level $ rmmod vmur
debugfs write debugfs_file_get() debug_unregister() mutex_lock(debug_mutex) debugfs_remove() wait for debugfs_file_put() debug_file_ops.write() debug_input() mutex_lock(debug_mutex) ==> DEADLOCK
Fix this by splitting debug_unregister() into an s390dbf and debugfs part, and running only the s390dbf part with debug_mutex locked.
{
"affected": [],
"aliases": [
"CVE-2026-90209"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-17T17:17:16Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/debug: Fix deadlock during unregister\n\nUnregistering an s390dbf debug area while one of the associated debugfs\nfiles is being written to can cause a deadlock:\n\n$ echo \u003e.../vmur/level $ rmmod vmur\n===================================================\ndebugfs write\ndebugfs_file_get()\n debug_unregister()\n mutex_lock(debug_mutex)\n debugfs_remove()\n wait for debugfs_file_put()\ndebug_file_ops.write()\ndebug_input()\nmutex_lock(debug_mutex) ==\u003e DEADLOCK\n\nFix this by splitting debug_unregister() into an s390dbf and debugfs\npart, and running only the s390dbf part with debug_mutex locked.",
"id": "GHSA-5fhq-j2h9-6qrx",
"modified": "2026-09-17T18:31:56Z",
"published": "2026-09-17T18:31:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90209"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/183f8f6d64bb0510070c856b9927618c53014a7b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/445c31ac638fd1af203d79bdf25fc0cb3149fbbc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/45bb341d1b73eb293e0dd43d9b72bbc8b615d0ba"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/54e1259b75d6402a1d0cfb822b9bb2c507e53dab"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5d83f3faa3fb7f23f298cfd40382611999de5d1d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a08b70ed2d1ec907353a72f15163b8e34ff4b2f8"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a214c3dacc779b2afcb0ac9c8001e45ee4ffb2ed"
}
],
"schema_version": "1.4.0",
"severity": []
}
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