Patch Name: PHCO_20018

Patch Description: s700_800 10.20 ksh(1) cumulative patch

Creation Date: 99/10/20

Post Date:  99/10/29

Repost: 01/09/30
	The patch documentation was modified to remove references to
	here-document related defects that are not fully addressed.
	The defects described in Service Request 1653182162
	(DSDe430660) and 1653264812 (DSDe443517) are not fully
	addressed in the patch so references to these defect fixes
	were removed from the patch documentation.

Hardware Platforms - OS Releases:
	s700: 10.20
	s800: 10.20

Products: N/A

Filesets:
	OS-Core.UX-CORE OS-Core.CORE-ENG-A-MAN

Automatic Reboot?: No

Status: General Superseded

Critical: No

Path Name: /hp-ux_patches/s700_800/10.X/PHCO_20018

Symptoms:
	PHCO_20018:
	1. ksh(1) manpage does not have information about history
	   file trimming.

	2. ksh(1) getopts OPTARG is trashed.

	3. ksh(1) fails to login when the history file is >4k and
	   older than 10 min.

	4. ksh(1) coredump with history in heterogenous environment.

	5. ksh: read not interrupted by a SIGINT. Works fine with
	   MR ksh.

	6. After trapping SIGHUP, ksh exits.

	7. ksh does not trap SIGHUP if received within a function.

	PHCO_17691:
	   ksh(1) coredumps with script using many
	   heredocs.

	PHCO_16363:
	1. A return statement in a do-while loop
	   inside a function exits only the do-while
	   loop, not the function.

	PHCO_16065:
	2. ksh does not handle command
	   substitution of variables of length 2047,
	   3071, etc. correctly. When a variable is
	   assigned a string of length equal to
	   2047/3071/..., the result of command
	   substitution using this variable retains
	   only the last 1023 bytes of the variable.

	PHCO_15648:
	   10.20 ksh subshell exits prematurely on a
	   uniprocessor. When ksh is executed from a
	   script on a uniprocessor, the shell exits by
	   itself, without the user typing an explicit
	   <exit>.

	PHCO_13698:
	1) ksh dies after sourcing .  ./script using while loop
	   and command redirect. Scripts like the following, when
	   sourced cause the shell to exit.

	   echo test |
	   while read r
	   do
		a=$(date)
	   done

	2) POSIX and Korn shell do not wait(2) for zombies
	   while in vi input mode

	PHCO_13655:

	Problem with set -e in ksh:
	When set -e is on, ksh  does not  exit on  encountering
	error while expanding the word list in a for statement.
	This happens even in a case  statement and a pipe list.

	PHCO_11347:

	1) Korn shell does not source a script if stderr is closed.

	   $cat prog
	   . sprog
	   $cat sprog
	   echo hello
	   $prog 2>&-          &lt;--- does not source 'sprog'
	   $

	2) trap DEBUG does not behave consistently with command
	   substitution.

	3) Shell builtin ':' (: > file) does not truncate
	   file when called second time from a function.

	4) Korh shell dumps core due to memory fault when
	   function is  defined in a loop.

	5) Korn shell adds character when parsing input for
	   trap action name

	   $cat prog
	   #!/usr/bin/ksh
	   trap $1 EXIT
	   echo t (d )
	   $./prog ate
	   prog[2]: syntax error at line 3 : `(' unexpected
	   Fri Jun 13 18:01:14 IST 1997 <-- 'd' from line 3 is added
						to action name 'ate'

	PHCO_11010:

	1) Korn shell dumps core during command substitution if
	   standard input is closed.

	2) Korn shell does not remove the temporary files when
	   it exits due to receipt of a signal.

	PHCO_10719:
	1) When ksh sees history file (using old internal magic
	   cookies) of pre-10.10 release, it simply unlinks
	   (discards) that history file.

	2) When any shell-builtin command returns NULL in command
	   substitution and the execution trace flag -x is on, then
	   the output of the next shell-builtin in command
	   substition is affected.

	PHCO_9484:

	1)  While using in-line command editing, characters
	    would sometimes appear that had not been typed
	    by the user, most commonly ^B.  Also, in editing
	    long history lines, especially near the end of
	    the lines, garbage characters would appear and
	    the line couldn't be edited properly.

	2)  ksh was leaving fd 10 [used for history file]
	    always open.  File descriptor 10 was being
	    reserved for use by the shell, but the file
	    descriptor was opened in a way that it would
	    remain open across an exec(2) system call.

	3)  ksh returns incorrect exit-status when it executes
	    'exit' command on trap.

	    For Example, When you run the following script
	    "trap.sh"

		#! /usr/bin/ksh
	        trap "_Exit" 0 1 2 3 15

		_Exit(){
		   exit
		}

	        rm FOOOOOOOO
	        ls FOOOOOOOO

	    $trap.sh
	    $echo $?
	    0

	    The exit-value of the above script should be of last
	    command executed that is 2 (exit value of ls FOOOOOOOO),
	    rather it will return 0.

	PHCO_9088:
	 1) Trap on EXIT set outside a function is not executed.
	    For example,

		trap 'echo exiting shell' EXIT
		f()
		{
		   exit
		}
		f

	    should output "exiting shell" but instead produces no
	    output.

	 3) cd -P and pwd -P can fail when current directory path
	    includes symbolic links where the link starts with ../
	    For example:

		cd /tmp
		mkdir test
		cd test
		ln -s ../../usr lnk
		cd lnk
		pwd -P

	    will produce the error "pwd: permission denied".

	 4) ksh hangs when processing "cat bigfile | while read ..."
	    The right side of the pipe can be any shell command
	    (while, if, for, etc.)

Defect Description:
	PHCO_20018:
	1. ksh manpage does not say anything about the history
	   file trimming.

	Resolution:
	   The necessery information regarding the trimming of
	   history file is added in the manpage.

	2. When getopts is executed it reads the option argument
	   from the command line and stores it in the static memory.
	   If we execute some other command before using the value
	   of OPTARG, the memory will be overwritten and the
	   argument is lost.

	Resolution:
	   To avoid this the argument that is read from the command
	   line is stored in the heap so that it will not be
	   corrupted.

	3. When the history file size is more than 4K and the file
	   is older than 10 minutes, there is some unwanted
	   recursion between the function which opens the history
	   file and the function which trims the history file.

	Resolution:
	   The resolution involves avoiding this unwanted recursion
	   by using a global flag.

	4. The problem was due to a corrupt .sh_history file which
	   was causing the shell to core dump. The problem was due
	   to an array buffer overflow.

	Resolution:
	   Now this array allocation has been changed to dynamic
	   allocation & this fixes the problem.

	5. When a script was executing a read command and a signal
	   was sent to it, the signal was not delivered until after
	   the completion of read.

	Resolution:
	   Now checking of trap has been introduced so as to catch
	   signals even during input processing.

	6. If SIGHUP is trapped and a SIGHUP signal received,
	   ksh(1) exits after executing the trap. It should
	   continue to run instead.

	Resolution:
	   ksh(1) was deliberately exiting after executing the
	   trap for SIGHUP. This part of the code has now been
	   eliminated, so that it continues to execute.

	7. The trap set for signal SIGHUP is not executed
	   by ksh(1), if it is received while a function
	   is being executed.

	Resolution:
	   When executing a function, ksh(1) resets all traps to
	   their default action. If SIGHUP was received while
	   executing a function, ksh(1) used to exit without
	   executing the trap set.
	   This specific check for SIGHUP has been now removed
	   so that ksh(1) does not exit immediately, but instead
	   executes the trap set and then exits.

	PHCO_17691:
	   ksh(1) dumps core while executing scripts
	   having large number of heredocs.

	Resolution:
	   ksh(1) had limited the number of open files at
	   any time to 20, which was not sufficient in the
	   case of the script which used a large number of
	   heredocs. ksh(1) didn't handle the case when
	   this limit was exceeded, and hence it coredumped.

	   ksh(1) now allows as many number of open files as
	   the system allows, i.e. it retrieves the system
	   configured value for the number of open files per
	   process and allocates sufficient memory to the
	   various data structures. Now, ksh(1) does not have
	   internal restriction on the number of open files
	   and handles the situation correctly by displaying
	   appropriate error messages, when the number of
	   open files is exceeded.

	PHCO_16363:
	   A return statement within a do-while loop
	   that is in a function, does not return from
	   the function, but exits only the do-while
	   loop. Running the following script demonstrates
	   this fact.

	#!/usr/bin/ksh

	fxn()
	{
	cat /etc/passwd | while read line
	do
	        echo $line
	        return
	done
	echo after fxn return, still in fxn
	}

	fxn
	echo after fxn

	   We see the message "after fxn return, still
	   in fxn" even after the return statement is
	   executed.

	PHCO_16065:
	2) ksh does not handle command
	   substitution of variables of length 2047,
	   3071, etc. correctly. In the following command,
	   where variable "stuff" is assigned a string of
	   length 2047, the contents of resulting string
	   "str" will be the last 1023 bytes of "stuff".

	   str=`echo $stuff`

	PHCO_15648:
	   10.20 Ksh subshell exits prematurely on a
	   uniprocessor. On uniprocessor machines running
	   one of 10.20, 10.10, 10.01 and 10.0 HP-UX'es,
	   the subshell run through a script exits by itself
	   without entering the exit routine.

	PHCO_13698:
	1) Scripts like the following when sourced, cause
	   the shell to exit.
	   echo test | while read r
	   do
		a=$(date)
	   done

	2) POSIX and Korn shell do not wait(2) for zombies
	   while in vi input mode.  Jobs which are started in
	   the background and exit show up as zombies (defunct)
	   until the user presses the return key in the xterm
	   where the job was started.

	PHCO_13655:
	If set -e is ON, ksh should exit on encountering errors
	during processing the word list in a for statement, and
	case  statement.  When the last  command in a pipe list
	fails  also, it should exit if set -e is on.  Currently
	it is not happening. Scripts like the following should
	exit on error.

	set -e
	for i in `sort a_non_existant_file`
	do
		echo Hello $i
	done
	echo "return code is " $? " -> Should not display this."

	PHCO_11347:
	1) Since file descriptor ERRIO (2) is used in parser, it
	   resets the i/o stream established with fd=2 when stderr
	   is closed.  This indirectly leads to syntax error while
	   parsing and hence aborts.

	2) trap DEBUG does not behave consistently with command
	   substitution.

	3) Shell builtin ':' (: > file) does not truncate
	   file when called second time from a function.

	4) Korh shell dumps core due to memory fault when
	   function is  defined in a loop.

	5) Unread (undo read) character in lexical analyser is
	   stored in shell data structure and this is added to input
	   for trap action name is read.

	PHCO_11010:
	1) When standard input is closed, the i/o channel
	   established using the file descriptor 0 for the command
	   substitution is not closed.  This further leads ksh to
	   bus error and hence make ksh dump core when it refers
	   invalid location in the memory.

	2) Korn shell does not clean up temporary files created when
	   it exits due to receipt of a signal.

	PHCO_10719:
	1) Since the internal magic cookies (H_UNDO & H_CMDNO) used
	   in history file were valid multibyte characters, the
	   cookies were changed to and hence aviod ambiguity when a
	   history file is read in multibyte locales, the old
	   history files were simply discarded.

	2) When any shell-builtin command returns NULL in command
	   substitution and the execution trace flag -x is on, then
	   it takes incorrect output from the I/O stream for next
	   shell-builtin command substition.

	        set -x
	        FOO=$(whence non_existing_file)
	        FOO=$(whence ls)
	        echo $FOO

	PHCO_9484:
	1)  While using in-line command editing, untyped
	    characters would sometimes appear, most often
	    ^B.  These occurred most typically when very
	    long command lines had been created.  Also,
	    in editing long history lines, especially
	    near the end of the lines, garbage characters
	    would appear and the line couldn't be edited
	    properly.

	2)  File descriptor 10 was being reserved for use by
	    the shell, but the file descriptor was opened in a
	    way that it would remain open across an exec(2)
	    system call.

	3)  ksh returns incorrect exit-status when it executes
	    'exit' command on trap.

	PHCO_9088:
	 1) A trap on EXIT set outside of a function is not
	    executed if an exit is called from within a
	    function.

	 3) cd -P and pwd -P generate nonexistent path names
	    when the logical path uses symbolic links containing
	    ..

	 4) ksh hangs when processing "cat bigfile | while read ..."
	    The right side of the pipe can be any shell command
	    (while, if, for, etc.)

SR:
	8606104865 1653298927 8606101547 8606103328 1653299891
	5003442533 5003455519 1653302570 1653298422 4701413922
	5003428490 5003424754 5003417931 1653239947 1653236851
	1653240390 1653240408 4701339309 1653164350 1653174615
	5003295741 5003340166 5003359547 1653210948 5003366856
	1653205088 1653152892 1653216481

Patch Files:
	/usr/bin/ksh
	/usr/bin/rksh
	/usr/share/man/man1.Z/ksh.1

what(1) Output:
	/usr/bin/ksh:
		$Revision: 78.5.1.45 $
		Version 11/16/88
		PATCH_10_20: arith.o blok.o ctype.o defs.o edit.o ec
			ho.o expand.o fault.o io.o string.o stak.o w
			ord.o emacs.o vi.o hpux_rel.o args.o builtin
			.o cmd.o main.o msg.o print.o xec.o name.o m
			acro.o error.o service.o test.o jobs.o histo
			ry.o 99/10/18
	/usr/bin/rksh:
		$Revision: 78.5.1.45 $
		Version 11/16/88
		PATCH_10_20: arith.o blok.o ctype.o defs.o edit.o ec
			ho.o expand.o fault.o io.o string.o stak.o w
			ord.o emacs.o vi.o hpux_rel.o args.o builtin
			.o cmd.o main.o msg.o print.o xec.o name.o m
			acro.o error.o service.o test.o jobs.o histo
			ry.o 99/10/18
	/usr/share/man/man1.Z/ksh.1:
		None

cksum(1) Output:
	3552933687 159744 /usr/bin/ksh
	3552933687 159744 /usr/bin/rksh
	3561129141 40993 /usr/share/man/man1.Z/ksh.1

Patch Conflicts: None

Patch Dependencies:
	s700: 10.20: PHCO_10718
	s800: 10.20: PHCO_10718

Hardware Dependencies: None

Other Dependencies:
	Since the POSIX sh(1) and the ksh(1) by default share the
	same history file it is advised to install the
	corresponding patches on all systems that access these.

	This is of particular interest in environments that mount
	home directories from a central NFS server.

	s700:  9.0X: PHCO_12193
	s700: 10.00: PHCO_10730 PHCO_10731
	s700: 10.01: PHCO_10728 PHCO_10729
	s700: 10.10: PHCO_10720 PHCO_10721
	s800:  9.0X: PHCO_12193
	s800: 10.00: PHCO_10730 PHCO_10731
	s800: 10.01: PHCO_10728 PHCO_10729
	s800: 10.10: PHCO_10720 PHCO_10721

Supersedes:
	PHCO_9088 PHCO_9484 PHCO_10719 PHCO_11010 PHCO_11347 PHCO_13655
	PHCO_13698 PHCO_15648 PHCO_16065 PHCO_16363 PHCO_17691

Equivalent Patches: None

Patch Package Size: 260 KBytes

Installation Instructions:
	Please review all instructions and the Hewlett-Packard
	SupportLine User Guide or your Hewlett-Packard support terms
	and conditions for precautions, scope of license,
	restrictions, and, limitation of liability and warranties,
	before installing this patch.
	------------------------------------------------------------
	1. Back up your system before installing a patch.

	2. Login as root.

	3. Copy the patch to the /tmp directory.

	4. Move to the /tmp directory and unshar the patch:

		cd /tmp
		sh PHCO_20018

	5a. For a standalone system, run swinstall to install the
	    patch:

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHCO_20018.depot

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHCO_20018.  If you do not wish to retain a
	copy of the original software, you can create an empty file
	named /var/adm/sw/patch/PATCH_NOSAVE.

	WARNING: If this file exists when a patch is installed, the
	         patch cannot be deinstalled.  Please be careful
		 when using this feature.

	It is recommended that you move the PHCO_20018.text file to
	/var/adm/sw/patch for future reference.

	To put this patch on a magnetic tape and install from the
	tape drive, use the command:

		dd if=/tmp/PHCO_20018.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions: None