git: 1771ab245c23 - main - nfsuserd.c: Fix handling where pw_name/gr_name differ from lookup name

From: Rick Macklem <rmacklem_at_FreeBSD.org>
Date: Mon, 07 Sep 2026 19:53:16 UTC
The branch main has been updated by rmacklem:

URL: https://cgit.FreeBSD.org/src/commit/?id=1771ab245c2341033f0cee3bd098c76888cf3515

commit 1771ab245c2341033f0cee3bd098c76888cf3515
Author:     Emanuel Helms <emanuel@nrv.cc>
AuthorDate: 2026-09-07 19:50:58 +0000
Commit:     Rick Macklem <rmacklem@FreeBSD.org>
CommitDate: 2026-09-07 19:50:58 +0000

    nfsuserd.c: Fix handling where pw_name/gr_name differ from lookup name
    
    When an NSS backend returns a canonical pw_name or gr_name that differs from
    the lookup name supplied by the NFSv4 upcall, nfsuserd stores the successful
    mapping in the kernel cache under the canonical name instead of the requested
    name.
    
    This causes the retry lookup performed by nfsv4_strtouid() or
    nfsv4_strtogid() to miss the newly inserted cache entry, resulting in the
    default UID/GID being returned although the NSS lookup itself succeeded.
    
    PR:     296753
    Reviewed by:    rmacklem
    Tested by:      Emanuel Helms <emanuel@nfv.cc>
    MFC after:      2 weeks
---
 usr.sbin/nfsuserd/nfsuserd.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/usr.sbin/nfsuserd/nfsuserd.c b/usr.sbin/nfsuserd/nfsuserd.c
index 9326dd9018e0..e6e215ad2a41 100644
--- a/usr.sbin/nfsuserd/nfsuserd.c
+++ b/usr.sbin/nfsuserd/nfsuserd.c
@@ -704,7 +704,8 @@ nfsuserdsrv(struct svc_req *rqstp, SVCXPRT *transp)
 		if (pwd != NULL) {
 			nid.nid_usertimeout = defusertimeout;
 			nid.nid_uid = pwd->pw_uid;
-			nid.nid_name = pwd->pw_name;
+			/* NSS may canonicalize the name used for the lookup. */
+			nid.nid_name = info.name;
 		} else {
 			nid.nid_usertimeout = 5;
 			nid.nid_uid = defaultuid;
@@ -737,7 +738,8 @@ nfsuserdsrv(struct svc_req *rqstp, SVCXPRT *transp)
 		if (grp != NULL) {
 			nid.nid_usertimeout = defusertimeout;
 			nid.nid_gid = grp->gr_gid;
-			nid.nid_name = grp->gr_name;
+			/* NSS may canonicalize the name used for the lookup. */
+			nid.nid_name = info.name;
 		} else {
 			nid.nid_usertimeout = 5;
 			nid.nid_gid = defaultgid;