libceph: reject buckets with mismatched CRUSH ids
In the Linux kernel, the following vulnerability has been resolved: libceph: reject buckets with mismatched CRUSH ids crush_decode() stores bucket data by array slot, and the mapper later derives the per-bucket workspace index from the decoded bucket id. A malformed map can therefore make one bucket reuse another bucket's workspace by encoding an id different from -1 - slot. For uniform buckets, the second replica selection expands the source bucket's permutation into that aliased workspace buffer. If the source bucket is larger than the aliased bucket, the write runs past the smaller permutation array and can escape the kvmalloc'd CRUSH workspace. KASAN reports a slab OOB write of 4 bytes in bucket_perm_choose(). Reject buckets whose encoded id does not match their array slot. Valid CRUSH maps already use the canonical negative id corresponding to the bucket slot, so this restores the invariant expected by work->work[-1 - in->id] without changing valid map behavior.
CVE-2026-89656
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89656
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "ee59040d6ed1a5f8d10d27174b8f32c90ca8e89a",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "baad5875fdd2f5e248250fc3519bb045d64f1716",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "4aeb93daadf388e72073abc204312dd364eeb30a",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "6e5c6ce252b1eccfd41670a5cf95ab44f7ba7022",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "3516a4131c4e45d62ee4e42e82c36930e8c1fbbd",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "00562ccd4e88d092b9b851df50fad20442bfeb24",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "79900d978158b2d80eef952fc41b9e4dc58d7b83",
"versionType": "git"
},
{
"status": "affected",
"version": "66a0e2d579dbec5c676cfe446234ffebb267c564",
"lessThan": "3cde4a8302301679937474a5f7a851394cc1bd11",
"versionType": "git"
}
],
"programFiles": [
"net/ceph/osdmap.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.11"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.11",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/ceph/osdmap.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89656
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #35149 · Revision 1
- Added to Heist Feed
- Publisher date