Merged revisions 131421 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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r131421 | russell | 2008-07-16 15:47:53 -0500 (Wed, 16 Jul 2008) | 7 lines

Always ensure that the channel's tech_pvt reference is NULL after calling the
destroy callback.
(closes issue #13060)
Reported by: jpgrayson
Patches:
      chan_iax2_tech_pvt_crash.patch uploaded by jpgrayson (license 492)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@131422 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_iax2.c

@@ -3738,6 +3738,12 @@ static int iax2_hangup(struct ast_channel *c)
 			ast_debug(1, "Really destroying %s now...\n", c->name);
 			iax2_destroy(callno);
 		}
+	} else if (c->tech_pvt) {
+		/* If this call no longer exists, but the channel still
+		 * references it we need to set the channel's tech_pvt to null
+		 * to avoid ast_channel_free() trying to free it.
+		 */
+		c->tech_pvt = NULL;
 	}
 	ast_mutex_unlock(&iaxsl[callno]);
 	ast_verb(3, "Hungup '%s'\n", c->name);