nfsd: size fh_verify server sockaddr slot by xpt_locallen
In the Linux kernel, the following vulnerability has been resolved: nfsd: size fh_verify server sockaddr slot by xpt_locallen The nfsd_fh_verify and nfsd_fh_verify_err tracepoints declare the server sockaddr slot sized by xpt_remotelen but fill it from xpt_local using xpt_locallen: TP_STRUCT__entry( ... __sockaddr(server, rqstp->rq_xprt->xpt_remotelen) ... ) TP_fast_assign( ... __assign_sockaddr(server, &rqstp->rq_xprt->xpt_local, rqstp->rq_xprt->xpt_locallen); ... ) When xpt_locallen exceeds xpt_remotelen, __assign_sockaddr's memcpy writes past the reserved ring-buffer slot. In the reverse direction (xpt_locallen < xpt_remotelen) the slot is oversized and the unwritten tail leaks prior ring-buffer contents to trace consumers. The write-past-end case is reachable on NFS/UDP. svc_xprt_set_remote() is only called from svc_tcp_accept() (net/sunrpc/svcsock.c) and from the RDMA connect path; svc_create_socket() for UDP calls only svc_xprt_set_local(), so xpt_remotelen stays 0 for the xprt's lifetime. Every fh_verify trace for an NFSv2/v3-over-UDP request then copies 16 or 28 bytes from xpt_local into a zero-byte slot. The other NFSD tracepoints that record the server address (NFSD_TRACE_PROC_CALL_FIELDS, NFSD_TRACE_PROC_RES_FIELDS, SVC_RQST_ENDPOINT_FIELDS) already size the server slot by xpt_locallen; nfsd_fh_verify and nfsd_fh_verify_err were the only exceptions. Fix by sizing the server slot with xpt_locallen so the declared slot matches the copy length. The client slot and its
CVE-2026-89702
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-2026-89702
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": "051382885552e12541cc0ebf82092be374a9ed2a",
"lessThan": "1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5",
"versionType": "git"
},
{
"status": "affected",
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
"lessThan": "95d064f9828a20ccca5ae90a17be3e2076f25272",
"versionType": "git"
},
{
"status": "affected",
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
"lessThan": "7ff8d6363cffff45654ea85e319f7c0c54226012",
"versionType": "git"
},
{
"status": "affected",
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
"lessThan": "719a10e3f5f868c3c4ac3cf3648c5775d12034bd",
"versionType": "git"
},
{
"status": "affected",
"version": "051382885552e12541cc0ebf82092be374a9ed2a",
"lessThan": "71d068490098b1d23c63b2345e40675d3a1ca763",
"versionType": "git"
},
{
"status": "affected",
"version": "dcbebc86850324fbe0a993ce352f0539cd98038a",
"versionType": "git"
},
{
"status": "affected",
"version": "62980365d6e894234b29f44fb2bfad4f7f8bb824",
"versionType": "git"
},
{
"status": "affected",
"version": "5.15.154",
"lessThan": "5.16",
"versionType": "semver"
}
],
"programFiles": [
"fs/nfsd/trace.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.0"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"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": [
"fs/nfsd/trace.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89702
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #46709 · Revision 1
- Added to Heist Feed
- Publisher date