diff --git a/backport-do-not-substract-from-UT_NAMESIZE-for-length-check.patch b/backport-do-not-substract-from-UT_NAMESIZE-for-length-check.patch
new file mode 100644
index 0000000000000000000000000000000000000000..2712269af36682b30bfb9ea1e0a56ebddc00442d
--- /dev/null
+++ b/backport-do-not-substract-from-UT_NAMESIZE-for-length-check.patch
@@ -0,0 +1,29 @@
+From f894632f15f48ad9075b19dc763622a991ff8d0b Mon Sep 17 00:00:00 2001
+From:  Michal Hlavinka <mhlavink@redhat.com>
+Date:  Wed Nov 6 11:54:15 2024 +0100
+Subject: [PATCH] do not substract from UT_NAMESIZE for length check
+
+---
+ lib/user.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/lib/user.c b/lib/user.c
+index 42f0c53..6b1cf7a 100644
+--- a/lib/user.c
++++ b/lib/user.c
+@@ -223,10 +223,10 @@ lu_name_allowed(struct lu_ent *ent, struct lu_error **error)
+ 		lu_error_new(error, lu_error_name_bad, _("name is too short"));
+ 		return FALSE;
+ 	}
+-	if (len > UT_NAMESIZE - 1) {
++	if (len > UT_NAMESIZE) {
+ 		lu_error_new(error, lu_error_name_bad,
+ 			     _("name is too long (%zu > %d)"), len,
+-			     UT_NAMESIZE - 1);
++			     UT_NAMESIZE);
+ 		return FALSE;
+ 	}
+ 	for (i = 0; sdata[i] != '\0'; i++) {
+-- 
+2.43.0
+
diff --git a/libuser.spec b/libuser.spec
index e4f67927d4e8ab7f2af7421fbe9f9b604c0d2bac..eb9770f64f62b96402d1dc6cdbdea87b34484028 100644
--- a/libuser.spec
+++ b/libuser.spec
@@ -1,11 +1,12 @@
 Name:    libuser
 Version: 0.64
-Release: 2
+Release: 3
 Summary: A user and group account administration library
 License: LGPLv2+
 URL:     https://pagure.io/libuser
 Source:  http://releases.pagure.org/libuser/libuser-%{version}.tar.gz
 
+Patch6000:  backport-do-not-substract-from-UT_NAMESIZE-for-length-check.patch
 Patch9000:  add-sm3-crypt-support.patch
 
 BuildRequires: cyrus-sasl-devel, linuxdoc-tools, pam-devel, popt-devel, gcc
@@ -101,6 +102,9 @@ python3 -c "import libuser"
 %{_mandir}/man5/*
 
 %changelog
+* Wed Aug 27 2025 jinshuaiyu <jinshuaiyu@kylinos.cn> - 0.64-3
+- backport upstream patch
+
 * Mon Apr 29 2024 fuanan <fuanan3@h-partners.com> - 0.64-2
 - Added 'Buildarch: noarch' to the help subpackage