tipc: Fix bugs in rejection of message with short header

This patch ensures that TIPC doesn't try to access non-existent
message header fields when rejecting a message with a short header.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/net/tipc/port.c b/net/tipc/port.c
index 93014f9bc95f..2e0cff408ff9 100644
--- a/net/tipc/port.c
+++ b/net/tipc/port.c
@@ -448,13 +448,15 @@ int tipc_reject_msg(struct sk_buff *buf, u32 err)
         msg_set_errcode(rmsg, err);
         msg_set_destport(rmsg, msg_origport(msg));
         msg_set_origport(rmsg, msg_destport(msg));
-        if (msg_short(msg))
+        if (msg_short(msg)) {
                 msg_set_orignode(rmsg, tipc_own_addr);
-        else
+                /* leave name type & instance as zeroes */
+        } else {
                 msg_set_orignode(rmsg, msg_destnode(msg));
+                msg_set_nametype(rmsg, msg_nametype(msg));
+                msg_set_nameinst(rmsg, msg_nameinst(msg));
+        }
         msg_set_size(rmsg, data_sz + hdr_sz);
-        msg_set_nametype(rmsg, msg_nametype(msg));
-        msg_set_nameinst(rmsg, msg_nameinst(msg));
         skb_copy_to_linear_data_offset(rbuf, hdr_sz, msg_data(msg), data_sz);
 
         /* send self-abort message when rejecting on a connected port */