Merged revisions 287661 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

........
  r287661 | alecdavis | 2010-09-21 10:21:50 +1200 (Tue, 21 Sep 2010) | 14 lines
  
  ast_do_masquerade. Keep channels ao2_container locked while unlink and linking channels.
  
  Previously, Masquerade would unlock 'original' and 'clonechan' and allow another masq thread to run.
  End result would be corrupted memory, and the frequent report 'Bad Magic Number'.
  
  (closes issue #17801,#17710)
  Reported by: notthematrix
  Patches: 
        Based on bug17801.diff1.txt uploaded by alecdavis (license 585)
  Tested by: alecdavis
  
  Review: https://reviewboard.asterisk.org/r/928
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@287671 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -5984,9 +5984,6 @@ int ast_do_masquerade(struct ast_channel *original)
 	ao2_unlink(channels, original);
 	ao2_unlink(channels, clonechan);
 
-	/* now that both channels are locked and unlinked from the container, it is safe to unlock it */
-	ao2_unlock(channels);
-
 	ast_debug(4, "Actually Masquerading %s(%d) into the structure of %s(%d)\n",
 		clonechan->name, clonechan->_state, original->name, original->_state);
 
@@ -6269,6 +6266,8 @@ done:
 		ao2_link(channels, original);
 	}
 
+	ao2_unlock(channels);
+
 	return 0;
 }