NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers
In the Linux kernel, the following vulnerability has been resolved: NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers flexfiles accepts NFSv4.0 data servers, but two NFSv4 code paths assume the data server client has a session. Unlike NFSv4.1+, an NFSv4.0 client has no session (clp->cl_session is NULL; it uses clp->cl_slot_tbl), so I/O to a v4.0 flexfiles DS oopses: - nfs4_init_ds_session() dereferences clp->cl_session->session_state while seeding the DS lease. It also only seeds cl_lease_time when NFS4_SESSION_INITING is set; without a session that never happens, so cl_lease_time stays 0 and nfs4_renew_state() busy-loops, requeuing every 5 seconds. Seed the lease whenever there is no session and return before touching session state. - ff_layout_async_handle_error_v4() dereferences clp->cl_session->fc_slot_table on every DS I/O error. Fall back to the v4.0 transport slot table (clp->cl_slot_tbl) when there is no session.
CVE-2026-90149
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-2026-90149
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": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "336b6da10021c69a8f273bbacdf7432fdc89a06f",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "5527af72b0100c94287bfec901b6313eeac567ca",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "163c16e01f53fc8eb8d0f3484ae6c382265ecbbd",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "436a214514e24103159aea455147d58b44a8a585",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc",
"versionType": "git"
}
],
"programFiles": [
"fs/nfs/flexfilelayout/flexfilelayout.c",
"fs/nfs/nfs4session.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.114",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/nfs/flexfilelayout/flexfilelayout.c",
"fs/nfs/nfs4session.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-90149
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #48616 · Revision 1
- Added to Heist Feed
- Publisher date