Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!fxgrp!ljz
From: ljz%fxgrp.fx.com@ames.arc.nasa.gov (Lloyd Zusman)
Newsgroups: comp.sources.bugs
Subject: Bug fix for APM library.
Message-ID: <LJZ.88Oct20122226%fxgrp.fx.com@ames.arc.nasa.gov>
Date: 20 Oct 88 19:22:26 GMT
Sender: ljz@fxgrp.UUCP
Organization: FX Development Group, Inc., Mountain View, California
Lines: 109

Here are the context diffs for a bug fix for the APM library, which
was posted to comp.sources.misc a couple weeks ago.  When converting
APM values to ASCII and right justifying, a segment violation could
occur due to a byte copy overflow.

Go to the directory where the APM source code is stored, make sure
that misc.c is writable, and then type 'patch <thisfile'.  If you
don't have Larry Wall's "patch" program, you can apply these diffs by
hand ... they aren't all that extensive.

Good luck.

--
  Lloyd Zusman                  Internet:  ljz@fx.com
  Master Byte Software                  or ljz%fx.com@ames.arc.nasa.gov
  Los Gatos, California                 or fxgrp!ljz@ames.arc.nasa.gov
  "We take things well in hand."    uucp:  ...!ames!fxgrp!ljz
  [ our Internet connection is down: use uucp or mail to the entry above it ]

--------------------------------- cut here ------------------------------------
*** /tmp/,RCSt1a10696	Thu Oct 20 12:10:37 1988
--- misc.c	Thu Oct 20 12:09:18 1988
***************
*** 2,13 ****
   * Miscellaneous routines for the APM library.
   *
   * $Log:	misc.c,v $
   * Revision 1.0  88/10/05  12:38:14  ljz
   * Initial release.
   * 
   */
  #ifndef lint
! static char rcsid[] = "$Header: misc.c,v 1.0 88/10/05 12:38:14 ljz Exp $";
  #endif /* ! lint */
  
  #include <stdio.h>
--- 2,16 ----
   * Miscellaneous routines for the APM library.
   *
   * $Log:	misc.c,v $
+  * Revision 1.1  88/10/20  10:45:15  ljz
+  * Fixed byte copy overflow in apm_convert.
+  * 
   * Revision 1.0  88/10/05  12:38:14  ljz
   * Initial release.
   * 
   */
  #ifndef lint
! static char rcsid[] = "$Header: misc.c,v 1.1 88/10/20 10:45:15 ljz Exp $";
  #endif /* ! lint */
  
  #include <stdio.h>
***************
*** 192,197 ****
--- 195,201 ----
  	static int localLen = 0;
  	int roffset;
  	int loffset;
+ 	int copylength;
  	int stringlen;
  	int dpos = -1;
  	int n;
***************
*** 315,334 ****
  		roffset = 0;
  		loffset = 0;
  		if (length > stringlen) {
! 			length = stringlen;
  		}
  	}
  	else if (stringlen >= length) {
  		roffset = 0;
  		loffset = stringlen - length;
  	}
  	else {
  		roffset = length - stringlen;
  		loffset = 0;
  	}
  
! 	APM_copy_bytes(result + roffset, localString + loffset, length);
! 	result[length] = '\0';
  	while (roffset-- > 0) {
  		result[roffset] = ' ';
  	}
--- 319,343 ----
  		roffset = 0;
  		loffset = 0;
  		if (length > stringlen) {
! 			copylength = stringlen;
  		}
+ 		else {
+ 			copylength = length;
+ 		}
  	}
  	else if (stringlen >= length) {
  		roffset = 0;
  		loffset = stringlen - length;
+ 		copylength = length;
  	}
  	else {
  		roffset = length - stringlen;
  		loffset = 0;
+ 		copylength = stringlen;
  	}
  
! 	APM_copy_bytes(result + roffset, localString + loffset, copylength);
! 	result[copylength] = '\0';
  	while (roffset-- > 0) {
  		result[roffset] = ' ';
  	}