[PATCH 06/13 net-next-2.6] [TIPC]: Prevent access of non-existent field in short message header

[Allan Stephens <allan.stephens@windriver.com>]

This patch eliminates a case where TIPC's link code could try reading
a field that is not present in a short message header.  (The random
value obtained was not being used, but the read operation could result
in an invalid memory access exception in extremely rare circumstances.)

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
---
 net/tipc/link.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index c62ebfe..022cb2f 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -2674,10 +2674,12 @@ int tipc_link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
 	u32 pack_sz = link_max_pkt(l_ptr);
 	u32 fragm_sz = pack_sz - INT_H_SIZE;
 	u32 fragm_no = 1;
-	u32 destaddr = msg_destnode(inmsg);
+	u32 destaddr;
 
 	if (msg_short(inmsg))
 		destaddr = l_ptr->addr;
+	else
+		destaddr = msg_destnode(inmsg);
 
 	if (msg_routed(inmsg))
 		msg_set_prevnode(inmsg, tipc_own_addr);
-- 
1.5.3.2