ceph: bound copied dentry name length in NFS export get_name
Published Sep 11, 2026
9.8
CRITICALCVSS 3.1
EPSS 0.46%
Description
ceph_get_name() copies the MDS-supplied name into the caller's NAME_MAX-sized buffer with memcpy(name, rinfo->dname, rinfo->dname_len) and then writes name[rinfo->dname_len] = 0, without checking dname_len against NAME_MAX. A malicious or buggy MDS that returns a LOOKUPNAME reply with dname_len > NAME_MAX overflows the buffer. __get_snap_name() copies rde->name / rde->name_len the same unchecked way.
Impact: a malicious or compromised Ceph MDS overflows the NAME_MAX name buffer in a client's NFS-export get_name path, a slab out-of-bounds write reported by KASAN. Reachable when a CephFS mount is re-exported over NFS.
Add ceph_export_copy_name(), which rejects lengths above NAME_MAX with -ENAMETOOLONG before the copy, and use it in both ceph_get_name() and __get_snap_name().
Affected products
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- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
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- Version 3.15StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<3.15
- Version 6.12.109StatusunaffectedConstraints<=6.12.*
- Version 6.18.50StatusunaffectedConstraints<=6.18.*
- Version 6.6.157StatusunaffectedConstraints<=6.6.*
- Version 7.2.4StatusunaffectedConstraints<=7.2.*
- Version 7.3-rc1StatusunaffectedConstraints<=*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
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| Linux | Linux | affected |
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No data.
No data.
Red Hat Enterprise Linux 10
kernel
Affected
Red Hat Enterprise Linux 10
kernel-rt
Affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Affected
Red Hat Enterprise Linux 7
kernel-rt
Affected
Red Hat Enterprise Linux 8
kernel
Affected
Red Hat Enterprise Linux 8
kernel-rt
Affected
Red Hat Enterprise Linux 9
kernel
Affected
Red Hat Enterprise Linux 9
kernel-rt
Affected
Red Hat OpenShift Container Platform 4
openshift/ose-rhel-coreos-8
Affected
Red Hat OpenShift Container Platform 4
openshift/ose-rhel-coreos-9
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 10 | kernel-rt | Affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Affected | n/a |
| Red Hat Enterprise Linux 8 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Affected | n/a |
| Red Hat Enterprise Linux 9 | kernel | Affected | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-8 | Affected | n/a |
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-9 | Affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (10)
- https://access.redhat.com/security/cve/CVE-2026-89652 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2532101 Issue Tracking
- https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89652.mbox
- https://git.kernel.org/stable/c/06fb5e623cdc2402d6bb29be94d9beb9a826ffec
- https://git.kernel.org/stable/c/61d9f27b191b838b96b697ce0bfaee39a138243a
- https://git.kernel.org/stable/c/a294064e0e0f81ea607b2f019e16888aa1b0a011
- https://git.kernel.org/stable/c/e7c2fd3893a7f7fcd7e8cf0b2c6348bb1e893df6
- https://git.kernel.org/stable/c/eff8013c5a8916613c742ae5a2cc341cb605c0ae
- https://nvd.nist.gov/vuln/detail/CVE-2026-89652
- https://www.cve.org/CVERecord?id=CVE-2026-89652
Change history (0)
No recorded changes yet.