| Message ID | 20201013171849.236025-3-kleber.souza@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | net: dccp: fix structure use-after-free | expand |
On 13/10/2020 19:18, Kleber Sacilotto de Souza wrote: > rom: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> > > 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@canonical.com> > Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> > --- Acked-by: Richard Sailer <richard_siegfried@systemli.org>
On Tue, 13 Oct 2020 19:18:49 +0200 Kleber Sacilotto de Souza wrote: > From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> > > 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 Does this person has an email address? > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> > Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
On 15.10.20 05:42, Jakub Kicinski wrote: > On Tue, 13 Oct 2020 19:18:49 +0200 Kleber Sacilotto de Souza wrote: >> From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> >> >> 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 > > Does this person has an email address? We have received this report via a private Launchpad bug and the submitter didn't provide any public email address, so we have only their name. > >> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> >> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
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);