ATM: CVE-2008-5079: duplicate listen() on socket corrupts the vcc table

As reported by Hugo Dias that it is possible to cause a local denial
of service attack by calling the svc_listen function twice on the same
socket and reading /proc/net/atm/*vc

Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Chas Williams 2008-12-04 14:58:13 -08:00 committed by David S. Miller
parent 2cc002c4bb
commit 17b24b3c97

View file

@ -293,7 +293,10 @@ static int svc_listen(struct socket *sock,int backlog)
error = -EINVAL;
goto out;
}
vcc_insert_socket(sk);
if (test_bit(ATM_VF_LISTEN, &vcc->flags)) {
error = -EADDRINUSE;
goto out;
}
set_bit(ATM_VF_WAITING, &vcc->flags);
prepare_to_wait(sk->sk_sleep, &wait, TASK_UNINTERRUPTIBLE);
sigd_enq(vcc,as_listen,NULL,NULL,&vcc->local);
@ -307,6 +310,7 @@ static int svc_listen(struct socket *sock,int backlog)
goto out;
}
set_bit(ATM_VF_LISTEN,&vcc->flags);
vcc_insert_socket(sk);
sk->sk_max_ack_backlog = backlog > 0 ? backlog : ATM_BACKLOG_DEFAULT;
error = -sk->sk_err;
out: