s390/debug: Fix deadlock during unregister
In 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.
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.15.221, 6.1.188, 6.12.110, 6.18.52, 6.6.157, 7.2.6
- CVEs
- CVE-2026-90209
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 17:42 UTC · Revision 1
Source evidence
s390/debug: Fix deadlock during unregister
core-osv · Original sourcePublished 17 Sept 2026, 16:07 UTC
In 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.
osv:CVE-2026-90209
Kernel
Fixed versions: 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6
Complete source record
{
"id": "6e3b69473fb23da464c8d489652bfbbc243e33b9bbc449ac21090a2dfd2020bd",
"url": "https://osv.dev/vulnerability/CVE-2026-90209",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "s390/debug: Fix deadlock during unregister",
"summary": "In 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.",
"evidence": "osv:CVE-2026-90209",
"products": [
{
"name": {
"value": "Kernel",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "5.15.221",
"evidence": "/affected/1/ranges"
},
{
"value": "6.1.188",
"evidence": "/affected/1/ranges"
},
{
"value": "6.6.157",
"evidence": "/affected/1/ranges"
},
{
"value": "6.12.110",
"evidence": "/affected/1/ranges"
},
{
"value": "6.18.52",
"evidence": "/affected/1/ranges"
},
{
"value": "7.2.6",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CVE-2026-90209",
"aliases": [
"CVE-2026-90209"
],
"affected": [
{
"ranges": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "9372a82892c2caa6bccab9a4081166fa769699f8"
},
{
"fixed": "a214c3dacc779b2afcb0ac9c8001e45ee4ffb2ed"
},
{
"fixed": "183f8f6d64bb0510070c856b9927618c53014a7b"
},
{
"fixed": "a08b70ed2d1ec907353a72f15163b8e34ff4b2f8"
},
{
"fixed": "45bb341d1b73eb293e0dd43d9b72bbc8b615d0ba"
},
{
"fixed": "5d83f3faa3fb7f23f298cfd40382611999de5d1d"
},
{
"fixed": "54e1259b75d6402a1d0cfb822b9bb2c507e53dab"
},
{
"fixed": "445c31ac638fd1af203d79bdf25fc0cb3149fbbc"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "5.4.146"
},
{
"fixed": "5.5"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "5.10.65"
},
{
"fixed": "5.11"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "5.13.17"
},
{
"fixed": "5.14"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "5.14.4"
},
{
"fixed": "5.15"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "c68ba4a708fbd0efdc384cd29250bb292a45e559"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "86f9980909f31ab205323eeeb290fe3cbb4952b4"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "fe5793e90d3f572a87ba67fe2f0e1679fdff14f8"
}
]
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "e234f66168f0d50c0d28154fb983a14e85c3c526"
}
]
}
],
"versions": [
"v5.4.302",
"v5.4.301",
"v5.4.300",
"v5.4.299",
"v5.4.298",
"v5.4.297",
"v5.4.296",
"v5.4.295",
"v5.4.294",
"v5.4.293",
"v5.4.292",
"v5.4.291",
"v5.4.290",
"v5.4.289",
"v5.4.288",
"v5.4.287",
"v5.4.286",
"v5.4.285",
"v5.4.284",
"v5.4.283",
"v5.4.282",
"v5.4.281",
"v5.4.280",
"v5.4.279",
"v5.4.278",
"v5.4.277",
"v5.4.276",
"v5.4.275",
"v5.4.274",
"v5.4.273",
"v5.4.272",
"v5.4.271",
"v5.4.270",
"v5.4.269",
"v5.4.268",
"v5.4.267",
"v5.4.266",
"v5.4.265",
"v5.4.264",
"v5.4.263",
"v5.4.262",
"v5.4.261",
"v5.4.260",
"v5.4.259",
"v5.4.258",
"v5.4.257",
"v5.4.256",
"v5.4.255",
"v5.4.254",
"v5.4.253",
"v5.4.252",
"v5.4.251",
"v5.4.250",
"v5.4.249",
"v5.4.248",
"v5.4.247",
"v5.4.246",
"v5.4.245",
"v5.4.244",
"v5.4.243",
"v5.4.242",
"v5.4.241",
"v5.4.240",
"v5.4.239",
"v5.4.238",
"v5.4.237",
"v5.4.236",
"v5.4.235",
"v5.4.234",
"v5.4.233",
"v5.4.232",
"v5.4.231",
"v5.4.230",
"v5.4.229",
"v5.4.228",
"v5.4.227",
"v5.4.226",
"v5.4.225",
"v5.4.224",
"v5.4.223",
"v5.4.222",
"v5.4.221",
"v5.4.220",
"v5.4.219",
"v5.4.218",
"v5.4.217",
"v5.4.216",
"v5.4.215",
"v5.4.214",
"v5.4.213",
"v5.4.212",
"v5.4.211",
"v5.4.210",
"v5.4.209",
"v5.4.208",
"v5.4.207",
"v5.4.206",
"v5.4.205",
"v5.4.204",
"v5.4.203",
"v5.4.202",
"v5.4.201",
"v5.4.200",
"v5.4.199",
"v5.4.198",
"v5.4.197",
"v5.4.196",
"v5.4.195",
"v5.4.194",
"v5.4.193",
"v5.4.192",
"v5.4.191",
"v5.4.190",
"v5.4.189",
"v5.4.188",
"v5.4.187",
"v5.4.186",
"v5.4.185",
"v5.4.184",
"v5.4.183",
"v5.4.182",
"v5.4.181",
"v5.4.180",
"v5.4.179",
"v5.4.178",
"v5.4.177",
"v5.4.176",
"v5.4.175",
"v5.4.174",
"v5.4.173",
"v5.4.172",
"v5.4.171",
"v5.4.170",
"v5.4.169",
"v5.4.168",
"v5.4.167",
"v5.4.166",
"v5.4.165",
"v5.4.164",
"v5.4.163",
"v5.4.162",
"v5.4.161",
"v5.4.160",
"v5.4.159",
"v5.4.158",
"v5.4.157",
"v5.4.156",
"v5.4.155",
"v5.4.154",
"v5.4.153",
"v5.4.152",
"v5.4.151",
"v5.4.150",
"v5.4.149",
"v5.4.148",
"v5.4.147",
"v5.4.146",
"v5.10.272",
"v5.10.271",
"v5.10.270",
"v5.10.269",
"v5.10.268",
"v5.10.267",
"v5.10.266",
"v5.10.265",
"v5.10.264",
"v5.10.263",
"v5.10.262",
"v5.10.261",
"v5.10.260",
"v5.10.259",
"v5.10.258",
"v5.10.257",
"v5.10.256",
"v5.10.255",
"v5.10.254",
"v5.10.253",
"v5.10.252",
"v5.10.251",
"v5.10.250",
"v5.10.249",
"v5.10.248",
"v5.10.247",
"v5.10.246",
"v5.10.245",
"v5.10.244",
"v5.10.243",
"v5.10.242",
"v5.10.241",
"v5.10.240",
"v5.10.239",
"v5.10.238",
"v5.10.237",
"v5.10.236",
"v5.10.235",
"v5.10.234",
"v5.10.233",
"v5.10.232",
"v5.10.231",
"v5.10.230",
"v5.10.229",
"v5.10.228",
"v5.10.227",
"v5.10.226",
"v5.10.225",
"v5.10.224",
"v5.10.223",
"v5.10.222",
"v5.10.221",
"v5.10.220",
"v5.10.219",
"v5.10.218",
"v5.10.217",
"v5.10.216",
"v5.10.215",
"v5.10.214",
"v5.10.213",
"v5.10.212",
"v5.10.211",
"v5.10.210",
"v5.10.209",
"v5.10.208",
"v5.10.207",
"v5.10.206",
"v5.10.205",
"v5.10.204",
"v5.10.203",
"v5.10.202",
"v5.10.201",
"v5.10.200",
"v5.10.199",
"v5.10.198",
"v5.10.197",
"v5.10.196",
"v5.10.195",
"v5.10.194",
"v5.10.193",
"v5.10.192",
"v5.10.191",
"v5.10.190",
"v5.10.189",
"v5.10.188",
"v5.10.187",
"v5.10.186",
"v5.10.185",
"v5.10.184",
"v5.10.183",
"v5.10.182",
"v5.10.181",
"v5.10.180",
"v5.10.179",
"v5.10.178",
"v5.10.177",
"v5.10.176",
"v5.10.175",
"v5.10.174",
"v5.10.173",
"v5.10.172",
"v5.10.171",
"v5.10.170",
"v5.10.169",
"v5.10.168",
"v5.10.167",
"v5.10.166",
"v5.10.165",
"v5.10.164",
"v5.10.163",
"v5.10.162",
"v5.10.161",
"v5.10.160",
"v5.10.159",
"v5.10.158",
"v5.10.157",
"v5.10.156",
"v5.10.155",
"v5.10.154",
"v5.10.153",
"v5.10.152",
"v5.10.151",
"v5.10.150",
"v5.10.149",
"v5.10.148",
"v5.10.147",
"v5.10.146",
"v5.10.145",
"v5.10.144",
"v5.10.143",
"v5.10.142",
"v5.10.141",
"v5.10.140",
"v5.10.139",
"v5.10.138",
"v5.10.137",
"v5.10.136",
"v5.10.135",
"v5.10.134",
"v5.10.133",
"v5.10.132",
"v5.10.131",
"v5.10.130",
"v5.10.129",
"v5.10.128",
"v5.10.127",
"v5.10.126",
"v5.10.125",
"v5.10.124",
"v5.10.123",
"v5.10.122",
"v5.10.121",
"v5.10.120",
"v5.10.119",
"v5.10.118",
"v5.10.117",
"v5.10.116",
"v5.10.115",
"v5.10.114",
"v5.10.113",
"v5.10.112",
"v5.10.111",
"v5.10.110",
"v5.10.109",
"v5.10.108",
"v5.10.107",
"v5.10.106",
"v5.10.105",
"v5.10.104",
"v5.10.103",
"v5.10.102",
"v5.10.101",
"v5.10.100",
"v5.10.99",
"v5.10.98",
"v5.10.97",
"v5.10.96",
"v5.10.95",
"v5.10.94",
"v5.10.93",
"v5.10.92",
"v5.10.91",
"v5.10.90",
"v5.10.89",
"v5.10.88",
"v5.10.87",
"v5.10.86",
"v5.10.85",
"v5.10.84",
"v5.10.83",
"v5.10.82",
"v5.10.81",
"v5.10.80",
"v5.10.79",
"v5.10.78",
"v5.10.77",
"v5.10.76",
"v5.10.75",
"v5.10.74",
"v5.10.73",
"v5.10.72",
"v5.10.71",
"v5.10.70",
"v5.10.69",
"v5.10.68",
"v5.10.67",
"v5.10.66",
"v5.10.65",
"v5.13.19",
"v5.13.18",
"v5.13.17",
"v5.14.21",
"v5.14.20",
"v5.14.19",
"v5.14.18",
"v5.14.17",
"v5.14.16",
"v5.14.15",
"v5.14.14",
"v5.14.13",
"v5.14.12",
"v5.14.11",
"v5.14.10",
"v5.14.9",
"v5.14.8",
"v5.14.7",
"v5.14.6",
"v5.14.5",
"v5.14.4"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90209.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.15.0"
},
{
"fixed": "5.15.221"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.16.0"
},
{
"fixed": "6.1.188"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.2.0"
},
{
"fixed": "6.6.157"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.7.0"
},
{
"fixed": "6.12.110"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.13.0"
},
{
"fixed": "6.18.52"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.19.0"
},
{
"fixed": "7.2.6"
}
]
}
],
"package": {
"name": "Kernel",
"ecosystem": "Linux"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90209.json"
}
}
],
"modified": "2026-10-28T02:30:21.787181010Z",
"provider": "osv",
"references": [
"https://git.kernel.org/stable/c/183f8f6d64bb0510070c856b9927618c53014a7b",
"https://git.kernel.org/stable/c/445c31ac638fd1af203d79bdf25fc0cb3149fbbc",
"https://git.kernel.org/stable/c/45bb341d1b73eb293e0dd43d9b72bbc8b615d0ba",
"https://git.kernel.org/stable/c/54e1259b75d6402a1d0cfb822b9bb2c507e53dab",
"https://git.kernel.org/stable/c/5d83f3faa3fb7f23f298cfd40382611999de5d1d",
"https://git.kernel.org/stable/c/a08b70ed2d1ec907353a72f15163b8e34ff4b2f8",
"https://git.kernel.org/stable/c/a214c3dacc779b2afcb0ac9c8001e45ee4ffb2ed",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90209.json",
"https://nvd.nist.gov/vuln/detail/CVE-2026-90209",
"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
],
"provider_metadata": {
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90209.json"
}
},
"related_cves": [
{
"value": "CVE-2026-90209",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 487903,
"published_at": "2026-09-17T16:07:24.126+00:00"
}