From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx> This reverts commit 2677d20677314101293e6da0094ede7b5526d2b1. This fixes an issue that after disconnect, dccps_hc_tx_ccid will still be kept, allowing the socket to be reused as a listener socket, and the cloned socket will free its dccps_hc_tx_ccid, leading to a later use after free, when the listener socket is closed. This addresses CVE-2020-16119. Fixes: 2677d2067731 (dccp: don't free ccid2_hc_tx_sock struct in dccp_disconnect()) Reported-by: Hadar Manor Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@xxxxxxxxxxxxx> --- net/dccp/proto.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/dccp/proto.c b/net/dccp/proto.c index 6d705d90c614..359e848dba6c 100644 --- a/net/dccp/proto.c +++ b/net/dccp/proto.c @@ -279,7 +279,9 @@ int dccp_disconnect(struct sock *sk, int flags) dccp_clear_xmit_timers(sk); ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk); + ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk); dp->dccps_hc_rx_ccid = NULL; + dp->dccps_hc_tx_ccid = NULL; __skb_queue_purge(&sk->sk_receive_queue); __skb_queue_purge(&sk->sk_write_queue); -- 2.25.1
