ceph: fix hanging __ceph_get_caps() with stale mds_wanted
In the Linux kernel, the following vulnerability has been resolved: ceph: fix hanging __ceph_get_caps() with stale mds_wanted A reader can hang forever in __ceph_get_caps() when the client no longer holds `FILE_RD`, but local cap state still says that the capability is already wanted (via `mds_wanted`). One way to trigger this is through MDS cap revocation. If another client performs a conflicting operation, the MDS can revoke `FILE_RD` from the reader; the next read then has to reacquire `FILE_RD`. If the cap update that should request `FILE_RD` never reaches the MDS after `cap->mds_wanted` was raised, the reader is left holding only non-file caps while local `mds_wanted` still includes the file read caps. In that state, try_get_cap_refs() sees `need <= mds_wanted` and returns 0, so __ceph_get_caps() just waits on `i_cap_wq`. If the cap update that was supposed to request `FILE_RD never reaches the MDS after `cap->mds_wanted was` raised, no further request is sent and the waiter can sleep indefinitely until unrelated cap traffic happens to wake it up. The ordering issue is that `cap->mds_wanted` is updated in __prep_cap() before the `CEPH_MSG_CLIENT_CAPS message` is actually queued for send. That makes one field serve two different meanings at once: what this client wants, and what the client believes the MDS already knows it wants. A proper fix would be to split those states and track whether a cap update is actually in flight or has been observed by the MDS. However, simpl
CVE-2026-80527
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-2026-80527
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": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "b5661524c5a45085a866864ca9b8ae2513dfd67a",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "5e84bc6f67e19fdd192d8b215de728acbfc12572",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "5fedf279a1ea369d39c8b06dd4547cdc576065d0",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "e05c315b4da0c16ea800ee4b2cb6c617f586d1b5",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "fcce1b3be6d286aa80831e730289f4c062053ae6",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "a3bc6b3e9ef3f5f5cb85a902a30a090c7931127c",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "9e55fe24c548ad3163903eb58bb002d28d32a630",
"versionType": "git"
},
{
"status": "affected",
"version": "0a454bdd501ad1aa30bb72e9581efa338ad6ce5c",
"lessThan": "50958bb928bad3bdba9e5d1b7ff4bbadcf6951e6",
"versionType": "git"
}
],
"programFiles": [
"fs/ceph/caps.c",
"fs/ceph/file.c",
"fs/ceph/mds_client.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.266",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.217",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.184",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.153",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.105",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.46",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.10",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/ceph/caps.c",
"fs/ceph/file.c",
"fs/ceph/mds_client.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-80527
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #34310 · Revision 1
- Added to Heist Feed
- Publisher date