dccp: CVE-2017-8824: use-after-free in DCCP code

commit 69c64866ce072dea1d1e59a0d61e0f66c0dffb76 upstream.

Whenever the sock object is in DCCP_CLOSED state,
dccp_disconnect() must free dccps_hc_tx_ccid and
dccps_hc_rx_ccid and set to NULL.

Signed-off-by: Mohamed Ghannam <simo.ghannam@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This commit is contained in:
Mohamed Ghannam 2017-12-05 20:58:35 +00:00 committed by syphyr
parent 67c46edd04
commit 3924c1e1de
1 changed files with 5 additions and 0 deletions

View File

@ -252,6 +252,7 @@ int dccp_disconnect(struct sock *sk, int flags)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct inet_sock *inet = inet_sk(sk);
struct dccp_sock *dp = dccp_sk(sk);
int err = 0;
const int old_state = sk->sk_state;
@ -271,6 +272,10 @@ int dccp_disconnect(struct sock *sk, int flags)
sk->sk_err = ECONNRESET;
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);