CVE-2026-89702
- Source
- https://cve.org/CVERecord?id=CVE-2026-89702
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89702.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-89702
- Downstream
AZL (1)
BELL (1)
DEBIAN (1)
MGASA (2)
openSUSE (2)
SUSE (9)
UBUNTU (1)
- Related
- Published
- 2026-09-11T19:46:19Z
- Modified
- 2026-10-24T02:30:56Z
- Severity
-
- 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- nfsd: size fh_verify server sockaddr slot by xpt_locallen
- Details
-
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 assignment already agree on xpt_remotelen and are left untouched.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89702.json" }- References
-
- https://git.kernel.org/stable/c/1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5
- https://git.kernel.org/stable/c/719a10e3f5f868c3c4ac3cf3648c5775d12034bd
- https://git.kernel.org/stable/c/71d068490098b1d23c63b2345e40675d3a1ca763
- https://git.kernel.org/stable/c/7ff8d6363cffff45654ea85e319f7c0c54226012
- https://git.kernel.org/stable/c/95d064f9828a20ccca5ae90a17be3e2076f25272
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89702.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-89702
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced051382885552e12541cc0ebf82092be374a9ed2aFixed1c6a4d6c20fd42552ffc2c3dfaed2139c9477ee5Fixed95d064f9828a20ccca5ae90a17be3e2076f25272Fixed7ff8d6363cffff45654ea85e319f7c0c54226012Fixed719a10e3f5f868c3c4ac3cf3648c5775d12034bdFixed71d068490098b1d23c63b2345e40675d3a1ca763
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.15.154Fixed5.16
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduceddcbebc86850324fbe0a993ce352f0539cd98038a
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced62980365d6e894234b29f44fb2bfad4f7f8bb824