tipc: eliminate unnecessary linearization of incoming buffers

Currently, TIPC linearizes all incoming buffers directly at reception
before passing them upwards in the stack. This is clearly a waste of
CPU resources, and must be avoided.

In this commit, we eliminate this unnecessary linearization. We still
ensure that at least the message header is linear, and that the buffer
is linearized where this is still needed, i.e. when unbundling and when
reversing messages.

In addition, we ensure that fragmented messages are validated after
reassembly before delivering them upwards in the stack.

Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 5 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 944c8c663a2d..8c6639d107fc 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1075,13 +1075,8 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
                 if (unlikely(!tipc_msg_validate(skb)))
                         goto discard;
 
-                /* Ensure message data is a single contiguous unit */
-                if (unlikely(skb_linearize(skb)))
-                        goto discard;
-
                 /* Handle arrival of a non-unicast link message */
                 msg = buf_msg(skb);
-
                 if (unlikely(msg_non_seq(msg))) {
                         if (msg_user(msg) ==  LINK_CONFIG)
                                 tipc_disc_rcv(net, skb, b_ptr);