diff --git a/CVE-2021-3571.patch b/CVE-2021-3571.patch
new file mode 100644
index 0000000000000000000000000000000000000000..57525147c5e0d05c229d1f9c90391e2a8e11ccb2
--- /dev/null
+++ b/CVE-2021-3571.patch
@@ -0,0 +1,26 @@
+From d61d77e163dbee247819f3d88593ba111577af15 Mon Sep 17 00:00:00 2001
+From: Miroslav Lichvar <mlichvar@redhat.com>
+Date: Fri, 26 Mar 2021 09:57:43 +0100
+Subject: [PATCH] tc: Fix length of follow-up message of one-step sync.
+
+Convert the length of the generated follow-up message to network order.
+This fixes reading and sending of data past the message buffer.
+
+Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
+---
+ tc.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/tc.c b/tc.c
+index d9e4853..2e3830c 100644
+--- a/tc.c
++++ b/tc.c
+@@ -452,7 +452,7 @@ int tc_fwd_sync(struct port *q, struct ptp_message *msg)
+ 		}
+ 		fup->header.tsmt               = FOLLOW_UP | (msg->header.tsmt & 0xf0);
+ 		fup->header.ver                = msg->header.ver;
+-		fup->header.messageLength      = sizeof(struct follow_up_msg);
++		fup->header.messageLength      = htons(sizeof(struct follow_up_msg));
+ 		fup->header.domainNumber       = msg->header.domainNumber;
+ 		fup->header.sourcePortIdentity = msg->header.sourcePortIdentity;
+ 		fup->header.sequenceId         = msg->header.sequenceId;
diff --git a/linuxptp.spec b/linuxptp.spec
index a00959d6014b93d9e3f590b4ecda12663c375d7f..90c7eb80684b1aacae95b053aee168db6787e545 100644
--- a/linuxptp.spec
+++ b/linuxptp.spec
@@ -1,6 +1,6 @@
 Name:		linuxptp
 Version:	2.0
-Release:        3
+Release:        4
 Summary:	Linuxptp is an implementation of the Precision Time Protocol (PTP)
 Group:		System Environment/Base
 License:	GPLv2+
@@ -8,6 +8,9 @@ URL:		http://linuxptp.sourceforge.net/
 Source0:	https://downloads.sourceforge.net/%{name}/%{name}-%{version}.tgz
 Source1:	phc2sys.service
 Source2:	ptp4l.service
+
+patch0000: CVE-2021-3571.patch
+
 BuildRequires:	gcc gcc-c++ systemd git net-tools
 
 
@@ -77,6 +80,9 @@ echo 'OPTIONS="-a -r"' > %{buildroot}%{_sysconfdir}/sysconfig/phc2sys
 %{_mandir}/man8/*.8*
 
 %changelog
+* Wed Jul 14 2021 houyingchao <houyingchao@huawei.com> - 2.0-4
+- fix CVE-2021-3571
+
 * Thu Nov 28 2019 openEuler BuildTeam<buildteam@openeuler.org> 2.0-3
 - Package Init