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 <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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 @@
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 @@
}
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 @@
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);