diff --git a/SOURCES/ksh-20120801-jobcontrol.patch b/SOURCES/ksh-20120801-jobcontrol.patch
new file mode 100644
index 0000000..903711d
--- /dev/null
+++ b/SOURCES/ksh-20120801-jobcontrol.patch
@@ -0,0 +1,47 @@
+From 27909acb584aed231d757d1d63c6c62b57c8e152 Mon Sep 17 00:00:00 2001
+From: Vincent Mihalkovic <vmihalko@redhat.com>
+Date: Mon, 3 Jan 2022 14:03:20 +0100
+Subject: [PATCH] Fix race conditions running external commands with job
+ control on
+
+When ksh is compiled with SHOPT_SPAWN (the default), which uses
+posix_spawn(3) or vfork(2) (via sh_ntfork()) to launch external
+commands, at least two race conditions occur when launching
+external commands while job control is active. See:
+https://bugs.launchpad.net/ubuntu/+source/ksh/+bug/1887863/comments/3
+https://www.mail-archive.com/ast-developers@research.att.com/msg00717.html
+
+The basic issue is that this performance optimisation is
+incompatible with job control, because it uses a spawning mechanism
+that doesn't copy the parent process' memory pages into the child
+process, therefore no state that involves memory can be set before
+exec-ing the external program. This makes it impossible to
+correctly set the terminal's process group ID in the child process,
+something that is essential for job control to work.
+
+src/cmd/ksh93/sh/xec.c:
+- Use sh_fork() instead of sh_ntfork() if job control is active.
+  This uses fork(2), which is 30%-ish slower on most sytems, but
+  allows for correctly setting the terminal process group.
+
+Fixes: https://github.com/ksh93/ksh/issues/79
+---
+ src/cmd/ksh93/sh/xec.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/cmd/ksh93/sh/xec.c b/src/cmd/ksh93/sh/xec.c
+index ae13178..be57a6b 100644
+--- a/src/cmd/ksh93/sh/xec.c
++++ b/src/cmd/ksh93/sh/xec.c
+@@ -1737,7 +1737,7 @@ int sh_exec(register const Shnode_t *t, int flags)
+ #else
+ #if SHOPT_SPAWN
+ #   ifdef _lib_fork
+-				if(com)
++				if(com && !job.jobcontrol)
+ 					parent = sh_ntfork(shp,t,com,&jobid,ntflag);
+ 				else
+ 					parent = sh_fork(shp,type,&jobid);
+-- 
+2.31.1
+
diff --git a/SPECS/ksh.spec b/SPECS/ksh.spec
index fe1adb8..6d5dfc2 100644
--- a/SPECS/ksh.spec
+++ b/SPECS/ksh.spec
@@ -6,7 +6,7 @@ Summary:      The Original ATT Korn Shell
 URL:          http://www.kornshell.com/
 License:      EPL
 Version:      %{releasedate}
-Release:      254%{?dist}
+Release:      255%{?dist}
 Source0:      http://www.research.att.com/~gsf/download/tgz/ast-ksh.%{release_date}.tgz
 Source1:      http://www.research.att.com/~gsf/download/tgz/INIT.%{release_date}.tgz
 Source2:      kshcomp.conf
@@ -217,6 +217,9 @@ Patch88: ksh-20120801-annocheck.patch
 # rhbz#1790547
 Patch89: ksh-20120801-cve-2019-14868.patch
 
+# rhbz#1857847
+Patch90: ksh-20120801-jobcontrol.patch
+
 Conflicts:    pdksh
 Requires: coreutils, diffutils, chkconfig
 BuildRequires: bison
@@ -369,6 +372,10 @@ fi
 %config(noreplace) %{_sysconfdir}/binfmt.d/kshcomp.conf
 
 %changelog
+* Mon Jan 03 2022 Vincent Mihalkovic <vmihalko@redhat.com> - 20120801-255
+- Fix race conditions running external commands with job control on
+  Resolves: #1857847
+
 * Thu Feb 06 2020 Siteshwar Vashisht <svashisht@redhat.com> - 20120801-254
 - Bump version number to avoid breaking upgrade path