diff --git a/SOURCES/libtirpc-1.1.4-dos-fix.patch b/SOURCES/libtirpc-1.1.4-dos-fix.patch
new file mode 100644
index 0000000..4b2c8eb
--- /dev/null
+++ b/SOURCES/libtirpc-1.1.4-dos-fix.patch
@@ -0,0 +1,154 @@
+diff --git a/src/rpc_com.h b/src/rpc_com.h
+index 10bec79..76badef 100644
+--- a/src/rpc_com.h
++++ b/src/rpc_com.h
+@@ -61,8 +61,7 @@ void __xprt_unregister_unlocked(SVCXPRT *);
+ void __xprt_set_raddr(SVCXPRT *, const struct sockaddr_storage *);
+ 
+ 
+-SVCXPRT **__svc_xports;
+-int __svc_maxrec;
++extern int __svc_maxrec;
+ 
+ #ifdef __cplusplus
+ }
+diff --git a/src/svc.c b/src/svc.c
+index b59467b..3a8709f 100644
+--- a/src/svc.c
++++ b/src/svc.c
+@@ -57,6 +57,9 @@
+ 
+ #define max(a, b) (a > b ? a : b)
+ 
++SVCXPRT **__svc_xports;
++int __svc_maxrec;
++
+ /*
+  * The services list
+  * Each entry represents a set of procedures (an rpc program).
+@@ -191,6 +194,21 @@ __xprt_do_unregister (xprt, dolock)
+     rwlock_unlock (&svc_fd_lock);
+ }
+ 
++int
++svc_open_fds()
++{
++	int ix;
++	int nfds = 0;
++
++	rwlock_rdlock (&svc_fd_lock);
++	for (ix = 0; ix < svc_max_pollfd; ++ix) {
++		if (svc_pollfd[ix].fd != -1)
++			nfds++;
++	}
++	rwlock_unlock (&svc_fd_lock);
++	return (nfds);
++}
++
+ /*
+  * Add a service program to the callout list.
+  * The dispatch routine will be called when a rpc request for this
+diff --git a/src/svc_vc.c b/src/svc_vc.c
+index c23cd36..1729963 100644
+--- a/src/svc_vc.c
++++ b/src/svc_vc.c
+@@ -64,6 +64,8 @@
+ 
+ 
+ extern rwlock_t svc_fd_lock;
++extern SVCXPRT **__svc_xports;
++extern int svc_open_fds();
+ 
+ static SVCXPRT *makefd_xprt(int, u_int, u_int);
+ static bool_t rendezvous_request(SVCXPRT *, struct rpc_msg *);
+@@ -82,6 +84,7 @@ static void svc_vc_ops(SVCXPRT *);
+ static bool_t svc_vc_control(SVCXPRT *xprt, const u_int rq, void *in);
+ static bool_t svc_vc_rendezvous_control (SVCXPRT *xprt, const u_int rq,
+ 				   	     void *in);
++static int __svc_destroy_idle(int timeout);
+ 
+ struct cf_rendezvous { /* kept in xprt->xp_p1 for rendezvouser */
+ 	u_int sendsize;
+@@ -312,13 +315,14 @@ done:
+ 	return (xprt);
+ }
+ 
++
+ /*ARGSUSED*/
+ static bool_t
+ rendezvous_request(xprt, msg)
+ 	SVCXPRT *xprt;
+ 	struct rpc_msg *msg;
+ {
+-	int sock, flags;
++	int sock, flags, nfds, cnt;
+ 	struct cf_rendezvous *r;
+ 	struct cf_conn *cd;
+ 	struct sockaddr_storage addr;
+@@ -378,6 +382,16 @@ again:
+ 
+ 	gettimeofday(&cd->last_recv_time, NULL);
+ 
++	nfds = svc_open_fds();
++	if (nfds >= (_rpc_dtablesize() / 5) * 4) {
++		/* destroy idle connections */
++		cnt = __svc_destroy_idle(15);
++		if (cnt == 0) {
++			/* destroy least active */
++			__svc_destroy_idle(0);
++		}
++	}
++
+ 	return (FALSE); /* there is never an rpc msg to be processed */
+ }
+ 
+@@ -819,3 +833,49 @@ __svc_clean_idle(fd_set *fds, int timeout, bool_t cleanblock)
+ {
+ 	return FALSE;
+ }
++
++static int
++__svc_destroy_idle(int timeout)
++{
++	int i, ncleaned = 0;
++	SVCXPRT *xprt, *least_active;
++	struct timeval tv, tdiff, tmax;
++	struct cf_conn *cd;
++
++	gettimeofday(&tv, NULL);
++	tmax.tv_sec = tmax.tv_usec = 0;
++	least_active = NULL;
++	rwlock_wrlock(&svc_fd_lock);
++
++	for (i = 0; i <= svc_max_pollfd; i++) {
++		if (svc_pollfd[i].fd == -1)
++			continue;
++		xprt = __svc_xports[i];
++		if (xprt == NULL || xprt->xp_ops == NULL ||
++			xprt->xp_ops->xp_recv != svc_vc_recv)
++			continue;
++		cd = (struct cf_conn *)xprt->xp_p1;
++		if (!cd->nonblock)
++			continue;
++		if (timeout == 0) {
++			timersub(&tv, &cd->last_recv_time, &tdiff);
++			if (timercmp(&tdiff, &tmax, >)) {
++				tmax = tdiff;
++				least_active = xprt;
++			}
++			continue;
++		}
++		if (tv.tv_sec - cd->last_recv_time.tv_sec > timeout) {
++			__xprt_unregister_unlocked(xprt);
++			__svc_vc_dodestroy(xprt);
++			ncleaned++;
++		}
++	}
++	if (timeout == 0 && least_active != NULL) {
++		__xprt_unregister_unlocked(least_active);
++		__svc_vc_dodestroy(least_active);
++		ncleaned++;
++	}
++	rwlock_unlock(&svc_fd_lock);
++	return (ncleaned);
++}
diff --git a/SPECS/libtirpc.spec b/SPECS/libtirpc.spec
index 259fee5..ff7f46c 100644
--- a/SPECS/libtirpc.spec
+++ b/SPECS/libtirpc.spec
@@ -2,7 +2,7 @@
 
 Name:			libtirpc
 Version:		1.1.4
-Release:		5%{?dist}
+Release:		6%{?dist}
 Summary:		Transport Independent RPC Library
 Group:		  	System Environment/Libraries
 License:		SISSL and BSD
@@ -31,6 +31,12 @@ Patch004: libtirpc-1.1.4-blacklist.patch
 # bz 1934866
 Patch005: libtirpc-1.1.4-disallow-auth_refresh.patch
 
+#
+# RHEL 8.6
+#
+# bz 1940341 
+Patch006: libtirpc-1.1.4-dos-fix.patch
+
 BuildRequires:		automake, autoconf, libtool, pkgconfig
 BuildRequires:		krb5-devel
 
@@ -150,6 +156,9 @@ mv %{buildroot}%{_mandir}/man3 %{buildroot}%{_mandir}/man3t
 %{_mandir}/*/*
 
 %changelog
+* Thu Dec  2 2021 Steve Dickson <steved@redhat.com> 1.1.4-6
+- Fix DoS vulnerability in libtirpc (bz 1940341)
+
 * Sat Apr 17 2021 Steve Dickson <steved@redhat.com> 1.1.4-5
 - blacklist: Add a few more well known ports (bz 1854147)
 - Disallow calling auth_refresh from clnt_call with RPCSEC_GSS (bz 1934866)