Fix segfault in strdup

Resolves: RHEL-11982

ksh-20120801-segfault-strdup.patch

@@ -0,0 +1,45 @@
+From 9a9da2c299a0adcd36b4efd1b1c0ee2883beba7b Mon Sep 17 00:00:00 2001
+From: Johnothan King <johnothanking@protonmail.com>
+Date: Mon, 6 Jul 2020 13:51:44 -0700
+Subject: [PATCH] Fix use of strdup on a NULL pointer (#63)
+
+The following set of commands can rarely cause a memory fault
+when auditing[*] is enabled, although most of the time it will
+simply cause ksh to write '(null)' to the auditing file in place
+of a tty name:
+
+$ [ -e /etc/ksh_audit ] || echo "/tmp/ksh_auditfile;$(id -u)" | sudo tee /etc/ksh_audit;
+$ v=$(ksh  2> /dev/null +o rc -ic $'getopts a:bc: opt --man\nprint $?')
+$ cat /tmp/ksh_auditfile
+1000;1593599493;(null); getopts a:bc: opt --man
+
+This happens because strdup is used unconditionally on the pointer
+returned by 'ttyname', which can be NULL if stderr is closed. This
+then causes 'hp->tty' to be set to null, as strdup returns NULL.
+See https://github.com/att/ast/issues/1028
+
+src/cmd/ksh93/edit/history.c:
+- Make strdup duplicate 'notty' instead of NULL to prevent
+  crashes.
+
+[*] https://blog.fpmurphy.com/2008/12/ksh93-auditing-and-accounting.html
+
+Cherry-picked-by: Lukáš Zaoral <lzaoral@redhat.com>
+Upstream-commit: 9a9da2c299a0adcd36b4efd1b1c0ee2883beba7b
+---
+ src/cmd/ksh93/edit/history.c    | 2 +-
+ 1 files changed, 1 insertions(+), 1 deletions(-)
+
+diff --git a/src/cmd/ksh93/edit/history.c b/src/cmd/ksh93/edit/history.c
+index d6737e209ca0..f40f27b4a4d7 100644
+--- a/src/cmd/ksh93/edit/history.c
++++ b/src/cmd/ksh93/edit/history.c
+@@ -395,7 +395,7 @@ int  sh_histinit(void *sh_context)
+ 			if(fd>=0)
+ 			{
+ 				fcntl(fd,F_SETFD,FD_CLOEXEC);
+-				hp->tty = strdup(ttyname(2));
++				hp->tty = strdup(isatty(2)?ttyname(2):"notty");
+ 				hp->auditfp = sfnew((Sfio_t*)0,NULL,-1,fd,SF_WRITE);
+ 			}
+ 		}

ksh.spec

@@ -6,7 +6,7 @@ Summary:      The Original ATT Korn Shell
 URL:          http://www.kornshell.com/
 License:      EPL-1.0
 Version:      %{releasedate}
-Release:      260%{?dist}
+Release:      261%{?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
@@ -240,6 +240,10 @@ Patch94: ksh-20120801-segfault-long-command.patch
 # upstream commit: https://github.com/ksh93/ksh/commit/74b4162178c8a2347491b9fd3a22d8e6e1b7e831
 Patch95: ksh-20120801-set+r-fix.patch
 
+# RHEL-11982
+# upstream commit: https://github.com/ksh93/ksh/commit/9a9da2c299a0adcd36b4efd1b1c0ee2883beba7b.patch
+Patch96: ksh-20120801-segfault-strdup.patch
+
 Conflicts:    pdksh
 Requires: coreutils, diffutils, chkconfig
 BuildRequires: bison
@@ -393,6 +397,10 @@ fi
 %config(noreplace) %{_sysconfdir}/binfmt.d/kshcomp.conf
 
 %changelog
+* Tue Oct 31 2023 Lukáš Zaoral <lzaoral@redhat.com> - 20120801-261
+- Fix segfault in strdup
+  Resolves: RHEL-11982
+
 * Mon Sep 18 2023 Lukáš Zaoral <lzaoral@redhat.com> - 20120801-260
 - Fix set +r so that it cannot unset the restricted option
   Resolves: #1948588