From: Mark Michelson <mmichelson@digium.com>
Date: Wed, 17 Jun 2009 20:05:39 +0000 (+0000)
Subject: Merged revisions 201458 via svnmerge from
X-Git-Tag: 1.6.1.3-rc1~145
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=311e463f484e176c6ffb9bf01496ad7338d12155;p=thirdparty%2Fasterisk.git

Merged revisions 201458 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

................
  r201458 | mmichelson | 2009-06-17 15:04:12 -0500 (Wed, 17 Jun 2009) | 15 lines

  Merged revisions 201450 via svnmerge from
  https://origsvn.digium.com/svn/asterisk/branches/1.4

  ........
    r201450 | mmichelson | 2009-06-17 14:59:31 -0500 (Wed, 17 Jun 2009) | 9 lines

    Change the datastore traversal in ast_do_masquerade to use a safe list traversal.

    It is possible for datastore fixup functions to remove the datastore from the list
    and free it. In particular, the queue_transfer_fixup in app_queue does this. While
    I don't yet know of this causing any crashes, it certainly could.

    Found while discussing a separate issue with Brian Degenhardt.
  ........
................


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.1@201460 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/main/channel.c b/main/channel.c
index de71c71a5b..967b1f9e06 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -4397,10 +4397,14 @@ int ast_do_masquerade(struct ast_channel *original)
 	/* Move data stores over */
 	if (AST_LIST_FIRST(&clonechan->datastores)) {
 		struct ast_datastore *ds;
-		AST_LIST_TRAVERSE(&clonechan->datastores, ds, entry) {
+		/* We use a safe traversal here because some fixup routines actually
+		 * remove the datastore from the list and free them.
+		 */
+		AST_LIST_TRAVERSE_SAFE_BEGIN(&clonechan->datastores, ds, entry) {
 			if (ds->info->chan_fixup)
 				ds->info->chan_fixup(ds->data, clonechan, original);
 		}
+		AST_LIST_TRAVERSE_SAFE_END;
 		AST_LIST_APPEND_LIST(&original->datastores, &clonechan->datastores, entry);
 	}