diff -Nru ksh-93u+20120801/debian/changelog ksh-93u+20120801/debian/changelog
--- ksh-93u+20120801/debian/changelog	2013-01-08 12:11:05.000000000 -0300
+++ ksh-93u+20120801/debian/changelog	2017-07-04 15:24:08.000000000 -0400
@@ -1,3 +1,10 @@
+ksh (93u+20120801-1ubuntu0.14.04.1) trusty; urgency=medium
+
+  * d/p/locking.patch: Fix job locking mechanism to prevent
+    ksh to segfaults in job_chksave after receiving SIGCHLD. (LP: #1697501)
+
+ -- Eric Desrochers <eric.desrochers@canonical.com>  Fri, 23 Jun 2017 16:01:04 -0400
+
 ksh (93u+20120801-1) unstable; urgency=low
 
   * New upstream release.
diff -Nru ksh-93u+20120801/debian/patches/locking.patch ksh-93u+20120801/debian/patches/locking.patch
--- ksh-93u+20120801/debian/patches/locking.patch	1969-12-31 21:00:00.000000000 -0300
+++ ksh-93u+20120801/debian/patches/locking.patch	2017-07-04 15:38:29.000000000 -0400
@@ -0,0 +1,37 @@
+Description: ksh segfaults in job_chksave after receiving SIGCHLD
+ Prior to this update, the compiler optimization dropped parts from the ksh job
+ locking mechanism from the binary code. As a consequence, ksh could terminate
+ unexpectedly with a segmentation fault after it received the SIGCHLD signal.
+ This update implements a fix to ensure the compiler does not drop parts of the
+ ksh mechanism and the crash no longer occurs.
+
+Author: Michal Hlavinka <mhlavink@redhat.com>
+Origin: Red Hat fix, ksh-20120801-locking.patch
+Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1123467
+Bug-Ubuntu: https://bugs.launchpad.net/bugs/1697501
+Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=867181
+--- a/src/cmd/ksh93/include/jobs.h
++++ b/src/cmd/ksh93/include/jobs.h
+@@ -149,15 +149,18 @@
+ #define vmbusy()	0
+ #endif
+ 
+-#define job_lock()	(job.in_critical++)
++#define asoincint(p)  __sync_fetch_and_add(p,1)
++#define asodecint(p)  __sync_fetch_and_sub(p,1)
++
++#define job_lock()      asoincint(&job.in_critical)
+ #define job_unlock()	\
+ 	do { \
+ 		int	sig; \
+-		if (!--job.in_critical && (sig = job.savesig)) \
++		if (asodecint(&job.in_critical)==1 && (sig = job.savesig)) \
+ 		{ \
+-			if (!job.in_critical++ && !vmbusy()) \
++			if (!asoincint(&job.in_critical) && !vmbusy()) \
+ 				job_reap(sig); \
+-			job.in_critical--; \
++			asodecint(&job.in_critical); \
+ 		} \
+ 	} while(0)
+ 
diff -Nru ksh-93u+20120801/debian/patches/series ksh-93u+20120801/debian/patches/series
--- ksh-93u+20120801/debian/patches/series	2012-07-12 01:20:06.000000000 -0400
+++ ksh-93u+20120801/debian/patches/series	2017-07-04 15:21:37.000000000 -0400
@@ -1,3 +1,4 @@
 shell-options.patch
 cleanup-man-title.patch
 no-rpath.patch
+locking.patch