Prereq: "2.8.19"
diff -cr --new-file /var/tmp/postfix-2.8.19/src/global/mail_version.h ./src/global/mail_version.h
*** /var/tmp/postfix-2.8.19/src/global/mail_version.h	2014-10-19 18:29:55.000000000 -0400
--- ./src/global/mail_version.h	2015-02-08 18:20:24.000000000 -0500
***************
*** 20,27 ****
    * Patches change both the patchlevel and the release date. Snapshots have no
    * patchlevel; they change the release date only.
    */
! #define MAIL_RELEASE_DATE	"20141019"
! #define MAIL_VERSION_NUMBER	"2.8.19"
  
  #ifdef SNAPSHOT
  # define MAIL_VERSION_DATE	"-" MAIL_RELEASE_DATE
--- 20,27 ----
    * Patches change both the patchlevel and the release date. Snapshots have no
    * patchlevel; they change the release date only.
    */
! #define MAIL_RELEASE_DATE	"20150208"
! #define MAIL_VERSION_NUMBER	"2.8.20"
  
  #ifdef SNAPSHOT
  # define MAIL_VERSION_DATE	"-" MAIL_RELEASE_DATE
diff -cr --new-file /var/tmp/postfix-2.8.19/HISTORY ./HISTORY
*** /var/tmp/postfix-2.8.19/HISTORY	2014-10-18 17:43:22.000000000 -0400
--- ./HISTORY	2015-02-08 18:02:50.000000000 -0500
***************
*** 17022,17024 ****
--- 17022,17036 ----
  	Cleanup: revert the workaround that places headers inserted
  	with PREPEND actions or policy requests BELOW Postfix's own
  	Received: message header. File: smtpd/smtpd.c.
+ 
+ 20150106
+ 
+ 	Robustness: don't segfault due to excessive recursion after
+ 	a faulty configuration runs into the virtual_alias_recursion_limit.
+ 	File: global/tok822_tree.c.
+ 
+ 20150115
+ 
+ 	Safety: stop aliasing loops that exponentially increase the
+ 	address length with each iteration. Back-ported from Postfix
+ 	3.0. File: cleanup/cleanup_map1n.c.
diff -cr --new-file /var/tmp/postfix-2.8.19/src/cleanup/cleanup_map1n.c ./src/cleanup/cleanup_map1n.c
*** /var/tmp/postfix-2.8.19/src/cleanup/cleanup_map1n.c	2010-12-05 18:53:37.000000000 -0500
--- ./src/cleanup/cleanup_map1n.c	2015-02-08 17:44:38.000000000 -0500
***************
*** 139,144 ****
--- 139,153 ----
  	    if ((lookup = mail_addr_map(maps, STR(state->temp1), propagate)) != 0) {
  		saved_lhs = mystrdup(argv->argv[arg]);
  		for (i = 0; i < lookup->argc; i++) {
+ 		    if (strlen(lookup->argv[i]) > var_line_limit) {
+ 			msg_warn("%s: unreasonable %s result %.300s... -- "
+ 				 "message not accepted, try again later",
+ 			     state->queue_id, maps->title, lookup->argv[i]);
+ 			state->errs |= CLEANUP_STAT_DEFER;
+ 			UPDATE(state->reason, "4.6.0 Alias expansion error");
+ 			UNEXPAND(argv, addr);
+ 			RETURN(argv);
+ 		    }
  		    unquote_822_local(state->temp1, lookup->argv[i]);
  		    if (i == 0) {
  			UPDATE(argv->argv[arg], STR(state->temp1));
diff -cr --new-file /var/tmp/postfix-2.8.19/src/global/tok822_tree.c ./src/global/tok822_tree.c
*** /var/tmp/postfix-2.8.19/src/global/tok822_tree.c	2000-11-20 13:05:32.000000000 -0500
--- ./src/global/tok822_tree.c	2015-01-06 12:51:58.000000000 -0500
***************
*** 259,269 ****
  
  TOK822 *tok822_free_tree(TOK822 *tp)
  {
!     if (tp) {
! 	if (tp->next)
! 	    tok822_free_tree(tp->next);
  	if (tp->head)
  	    tok822_free_tree(tp->head);
  	tok822_free(tp);
      }
      return (0);
--- 259,270 ----
  
  TOK822 *tok822_free_tree(TOK822 *tp)
  {
!     TOK822 *next;
! 
!     for (/* void */; tp != 0; tp = next) {
  	if (tp->head)
  	    tok822_free_tree(tp->head);
+ 	next = tp->next;
  	tok822_free(tp);
      }
      return (0);