From: Michal Ostrowski Subject: [PATCH 3/4] PPPOE: memory leak when socket is release()d before PPPIOCGCHAN has been called on it Date: Tue, 13 Mar 2007 09:09:34 -0500 Message-ID: <11737949751582-git-send-email-mostrows@earthlink.net> References: <11737949753580-git-send-email-mostrows@earthlink.net> <1173794975536-git-send-email-mostrows@earthlink.net> Cc: Florian Zumbiehl To: mostrows@watson.ibm.com, davem@davemloft.net, netdev@vger.kernel.org Return-path: Received: from igw2.watson.ibm.com ([129.34.20.6]:47129 "EHLO igw2.watson.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965755AbXCMOHW (ORCPT ); Tue, 13 Mar 2007 10:07:22 -0400 In-Reply-To: <1173794975536-git-send-email-mostrows@earthlink.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org below you find a patch that fixes a memory leak when a PPPoE socket is release()d after it has been connect()ed, but before the PPPIOCGCHAN ioctl ever has been called on it. This is somewhat of a security problem, too, since PPPoE sockets can be created by any user, so any user can easily allocate all the machine's RAM to non-swappable address space and thus DoS the system. Is there any specific reason for PPPoE sockets being available to any unprivileged process, BTW? After all, you need a packet socket for the discovery stage anyway, so it's unlikely that any unprivileged process will ever need to create a PPPoE socket, no? Allocating all session IDs for a known AC is a kind of DoS, too, after all - with Juniper ERXes, this is really easy, actually, since they don't ever assign session ids above 8000 ... Signed-off-by: Florian Zumbiehl Acked-by: Michal Ostrowski --- drivers/net/pppox.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/net/pppox.c b/drivers/net/pppox.c index 9315046..3f8115d 100644 --- a/drivers/net/pppox.c +++ b/drivers/net/pppox.c @@ -58,7 +58,7 @@ void pppox_unbind_sock(struct sock *sk) { /* Clear connection to ppp device, if attached. */ - if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE)) { + if (sk->sk_state & (PPPOX_BOUND | PPPOX_CONNECTED | PPPOX_ZOMBIE)) { ppp_unregister_channel(&pppox_sk(sk)->chan); sk->sk_state = PPPOX_DEAD; } -- 1.5.0.g78e90