[PATCH net 03/14] mptcp: syncookies: remember the request backup flag

[Matthieu Baerts (NGI0)]

Instead of using an uninitialised bit when copying the info in
subflow_ulp_clone().

To fix this, no need to extend the join_entry structure: backup is
coming from struct mptcp_subflow_request_sock, only one bit. Do the same
here by using one bit for both.

Fixes: 9466a1ccebbe ("mptcp: enable JOIN requests even if cookies are in use")
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Geliang Tang <geliang@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
---
Cc: Florian Westphal <fw@xxxxxxxxx>
Note: Peter Krystad's email address is bouncing.
---
 net/mptcp/syncookies.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/syncookies.c b/net/mptcp/syncookies.c
index b5cac5701122..9474706641c1 100644
--- a/net/mptcp/syncookies.c
+++ b/net/mptcp/syncookies.c
@@ -26,7 +26,8 @@ struct join_entry {
 	u32 local_nonce;
 	u8 join_id;
 	u8 local_id;
-	u8 backup;
+	u8 backup:1,
+	   request_bkup:1;
 	u8 valid;
 };
 
@@ -63,6 +64,7 @@ static void mptcp_join_store_state(struct join_entry *entry,
 	entry->remote_nonce = subflow_req->remote_nonce;
 	entry->local_nonce = subflow_req->local_nonce;
 	entry->backup = subflow_req->backup;
+	entry->request_bkup = subflow_req->request_bkup;
 	entry->join_id = subflow_req->remote_id;
 	entry->local_id = subflow_req->local_id;
 	entry->valid = 1;
@@ -117,6 +119,7 @@ bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subfl
 	subflow_req->remote_nonce = e->remote_nonce;
 	subflow_req->local_nonce = e->local_nonce;
 	subflow_req->backup = e->backup;
+	subflow_req->request_bkup = e->request_bkup;
 	subflow_req->remote_id = e->join_id;
 	subflow_req->local_id = e->local_id;
 	subflow_req->token = e->token;

-- 
2.53.0