<Vulnerability name="CVE-2026-89652">
    <DocumentDistribution xml:lang="en">Copyright © 2012 Red Hat, Inc. All rights reserved.</DocumentDistribution>
    <ThreatSeverity>Important</ThreatSeverity>
    <PublicDate>2026-09-11T00:00:00</PublicDate>
    <Bugzilla id="2532101" url="https://bugzilla.redhat.com/show_bug.cgi?id=2532101" xml:lang="en:us">
kernel: ceph: bound copied dentry name length in NFS export get_name
    </Bugzilla>
    <CVSS3 status="draft">
        <CVSS3BaseScore>7.0</CVSS3BaseScore>
        <CVSS3ScoringVector>CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H</CVSS3ScoringVector>
    </CVSS3>
    <CWE>CWE-120</CWE>
    <Details xml:lang="en:us" source="Mitre">
In the Linux kernel, the following vulnerability has been resolved:

ceph: bound copied dentry name length in NFS export get_name

ceph_get_name() copies the MDS-supplied name into the caller's
NAME_MAX-sized buffer with memcpy(name, rinfo-&gt;dname, rinfo-&gt;dname_len)
and then writes name[rinfo-&gt;dname_len] = 0, without checking dname_len
against NAME_MAX. A malicious or buggy MDS that returns a LOOKUPNAME reply
with dname_len &gt; NAME_MAX overflows the buffer. __get_snap_name() copies
rde-&gt;name / rde-&gt;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().
    </Details>
    <Details xml:lang="en:us" source="Red Hat">
A flaw was found in the Linux kernel's Ceph file system. A malicious or compromised Ceph Metadata Server (MDS) can send a specially crafted `LOOKUPNAME` reply that causes a buffer overflow when copying dentry names during an NFS export operation. This out-of-bounds write can lead to memory corruption on the client system, particularly when a CephFS mount is re-exported over NFS.
    </Details>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:10">
        <ProductName>Red Hat Enterprise Linux 10</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:6">
        <ProductName>Red Hat Enterprise Linux 6</ProductName>
        <FixState>Not affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:7">
        <ProductName>Red Hat Enterprise Linux 7</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:8">
        <ProductName>Red Hat Enterprise Linux 8</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/o:redhat:enterprise_linux:9">
        <ProductName>Red Hat Enterprise Linux 9</ProductName>
        <FixState>Affected</FixState>
        <PackageName>kernel-rt</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/a:redhat:openshift:4">
        <ProductName>Red Hat OpenShift Container Platform 4</ProductName>
        <FixState>Affected</FixState>
        <PackageName>openshift/ose-rhel-coreos-8</PackageName>
    </PackageState>
    <PackageState cpe="cpe:/a:redhat:openshift:4">
        <ProductName>Red Hat OpenShift Container Platform 4</ProductName>
        <FixState>Affected</FixState>
        <PackageName>openshift/ose-rhel-coreos-9</PackageName>
    </PackageState>
    <References xml:lang="en:us">
https://www.cve.org/CVERecord?id=CVE-2026-89652
https://nvd.nist.gov/vuln/detail/CVE-2026-89652
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89652.mbox
    </References>
</Vulnerability>