[TCP] MTUprobe: fix potential sk_send_head corruption

When the abstraction functions got added, conversion here was
made incorrectly. As a result, the skb may end up pointing
to skb which got included to the probe skb and then was freed.
For it to trigger, however, skb_transmit must fail sending as
well.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 1 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 324b4207254a..e48e28e7d539 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1352,7 +1352,6 @@ static int tcp_mtu_probe(struct sock *sk)
 
         skb = tcp_send_head(sk);
         tcp_insert_write_queue_before(nskb, skb, sk);
-        tcp_advance_send_head(sk, skb);
 
         TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(skb)->seq;
         TCP_SKB_CB(nskb)->end_seq = TCP_SKB_CB(skb)->seq + probe_size;