[net 1/1] tipc: initialize 'validated' field of received packets

[net 1/1] tipc: initialize 'validated' field of received packets

[Jon Maloy]

The tipc_msg_validate() function leaves a boolean flag 'validated' in
the validated buffer's control block, to avoid performing this action
more than once. However, at reception of new packets, the position of
this field may already have been set by lower layer protocols, so
that the packet is erroneously perceived as already validated by TIPC.

We fix this by initializing the said field to 'false' before performing
the initial validation.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/node.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/tipc/node.c b/net/tipc/node.c
index 324a1f9..3a5be1d 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -1807,6 +1807,7 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 	__skb_queue_head_init(&xmitq);
 
 	/* Ensure message is well-formed before touching the header */
+	TIPC_SKB_CB(skb)->validated = false;
 	if (unlikely(!tipc_msg_validate(&skb)))
 		goto discard;
 	hdr = buf_msg(skb);
-- 
2.1.4

Re: [net 1/1] tipc: initialize 'validated' field of received packets

[David Miller]

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Wed, 17 Jul 2019 23:43:44 +0200

> The tipc_msg_validate() function leaves a boolean flag 'validated' in
> the validated buffer's control block, to avoid performing this action
> more than once. However, at reception of new packets, the position of
> this field may already have been set by lower layer protocols, so
> that the packet is erroneously perceived as already validated by TIPC.
> 
> We fix this by initializing the said field to 'false' before performing
> the initial validation.
> 
> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>

Applied.