From: Rémi Denis-Courmont <remi@xxxxxxxxxx> commit 75a2f31520095600f650597c0ac41f48b5ba0068 upstream. This ioctl() implicitly assumed that the socket was already bound to a valid local socket name, i.e. Phonet object. If the socket was not bound, two separate problems would occur: 1) We'd send an pipe enablement request with an invalid source object. 2) Later socket calls could BUG on the socket unexpectedly being connected yet not bound to a valid object. Reported-by: syzbot+2dc91e7fc3dea88b1e8a@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Rémi Denis-Courmont <remi@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/phonet/pep.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/phonet/pep.c +++ b/net/phonet/pep.c @@ -956,6 +956,8 @@ static int pep_ioctl(struct sock *sk, in ret = -EBUSY; else if (sk->sk_state == TCP_ESTABLISHED) ret = -EISCONN; + else if (!pn->pn_sk.sobject) + ret = -EADDRNOTAVAIL; else ret = pep_sock_enable(sk, NULL, 0); release_sock(sk);