From 9f6bdcd4286145e812058e4111e906e9830514d8 Mon Sep 17 00:00:00 2001 From: Allan Stephens Date: Thu, 7 Apr 2011 14:57:53 -0400 Subject: [PATCH] tipc: Discard incoming broadcast messages that are unexpected Modifies TIPC's incoming broadcast packet handler to discard messages that cannot legally be sent over the broadcast link, including: - broadcast protocol messages that do no contain state information - payload messages that are not named multicast messages - any other form of message except for bundled messages, fragmented messages, and name distribution messages. These checks are needed to prevent TIPC from handing an unexpected message to a routine that isn't prepared to handle it, which could lead to incorrect processing (up to and including invalid memory references caused by attempts to access message fields that aren't present in the message). Signed-off-by: Allan Stephens Signed-off-by: Paul Gortmaker --- net/tipc/bcast.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c index 8d29852..bead28b 100644 --- a/net/tipc/bcast.c +++ b/net/tipc/bcast.c @@ -39,6 +39,7 @@ #include "link.h" #include "port.h" #include "bcast.h" +#include "name_distr.h" #define MAX_PKT_DEFAULT_MCAST 1500 /* bcast link max packet size (fixed) */ @@ -445,6 +446,8 @@ void tipc_bclink_recv_pkt(struct sk_buff *buf) goto unlock; if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) { + if (msg_type(msg) != STATE_MSG) + goto unlock; if (msg_destnode(msg) == tipc_own_addr) { tipc_bclink_acknowledge(node, msg_bcast_ack(msg)); tipc_node_unlock(node); @@ -480,7 +483,10 @@ receive: } if (likely(msg_isdata(msg))) { tipc_node_unlock(node); - tipc_port_recv_mcast(buf, NULL); + if (likely(msg_mcast(msg))) + tipc_port_recv_mcast(buf, NULL); + else + buf_discard(buf); } else if (msg_user(msg) == MSG_BUNDLER) { bcl->stats.recv_bundles++; bcl->stats.recv_bundled += msg_msgcnt(msg); @@ -493,9 +499,12 @@ receive: bcl->stats.recv_fragmented++; tipc_node_unlock(node); tipc_net_route_msg(buf); + } else if (msg_user(msg) == NAME_DISTRIBUTOR) { + tipc_node_unlock(node); + tipc_named_recv(buf); } else { tipc_node_unlock(node); - tipc_net_route_msg(buf); + buf_discard(buf); } buf = NULL; tipc_node_lock(node); -- 2.7.4