Ensure that the stored CDR reference is still valid after the bridge before

poking at it.  Also, keep the channel locked while messing with this CDR.

(fixes crashes reported in issue #13409)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@142063 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_features.c

@@ -1678,6 +1678,22 @@ int ast_bridge_call(struct ast_channel *chan,struct ast_channel *peer,struct ast
 			ast_cdr_specialized_reset(chan->cdr,0);
 		}
 		if (peer->cdr) {
+			struct ast_cdr *cur;
+
+			ast_channel_lock(peer);
+			for (cur = peer->cdr; cur; cur = cur->next) {
+				if (cur == orig_peer_cdr) {
+					break;
+				}
+			}
+
+			if (!cur) {
+				/* orig_peer_cdr is gone, probably because of a masquerade
+				 * during the bridge. */
+				ast_channel_unlock(peer);
+				return res;
+			}
+
 			/* before resetting the peer cdr, throw a copy of it to the
 			   backend, just in case the cdr.conf file is calling for
 			   unanswered CDR's. */
@@ -1694,6 +1710,7 @@ int ast_bridge_call(struct ast_channel *chan,struct ast_channel *peer,struct ast
 				}
 			}
 			ast_cdr_specialized_reset(orig_peer_cdr,0);
+			ast_channel_unlock(peer);
 		}
 	}
 	return res;