From patchwork Wed May 22 12:59:07 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Slaby X-Patchwork-Id: 245609 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 21F542C0098 for ; Wed, 22 May 2013 23:00:55 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754839Ab3EVM6k (ORCPT ); Wed, 22 May 2013 08:58:40 -0400 Received: from ip4-83-240-18-99.cust.nbox.cz ([83.240.18.99]:50082 "EHLO anemoi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754152Ab3EVM6j (ORCPT ); Wed, 22 May 2013 08:58:39 -0400 Received: from ku by anemoi with local (Exim 4.80.1) (envelope-from ) id 1Uf8dM-000341-3d; Wed, 22 May 2013 14:59:12 +0200 From: Jiri Slaby To: jirislaby@gmail.com Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, Jeff Mahoney , Patrick Koppen , Jiri Slaby , Karsten Keil , netdev@vger.kernel.org, "David S. Miller" Subject: [PATCH -resend 1/6] mISDN: Add support for group membership check Date: Wed, 22 May 2013 14:59:07 +0200 Message-Id: <1369227552-11743-1-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 1.8.2.3 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jeff Mahoney This patch adds a module parameter to allow a group access to the mISDN devices. Otherwise, unpriviledged users on systems with ISDN hardware have the ability to dial out, potentially causing expensive bills. Based on a different implementation by Patrick Koppen Acked-by: Jeff Mahoney Cc: Patrick Koppen Signed-off-by: Jiri Slaby Cc: Karsten Keil Cc: netdev@vger.kernel.org Cc: "David S. Miller" --- drivers/isdn/mISDN/core.c | 3 +++ drivers/isdn/mISDN/core.h | 1 + drivers/isdn/mISDN/socket.c | 8 ++++++++ 3 files changed, 12 insertions(+) diff --git a/drivers/isdn/mISDN/core.c b/drivers/isdn/mISDN/core.c index da30c5c..a7050c3 100644 --- a/drivers/isdn/mISDN/core.c +++ b/drivers/isdn/mISDN/core.c @@ -21,10 +21,13 @@ #include "core.h" static u_int debug; +u_int misdn_permitted_gid; MODULE_AUTHOR("Karsten Keil"); MODULE_LICENSE("GPL"); module_param(debug, uint, S_IRUGO | S_IWUSR); +module_param_named(gid, misdn_permitted_gid, uint, 0); +MODULE_PARM_DESC(gid, "Unix group for accessing misdn socket (default 0)"); static u64 device_ids; #define MAX_DEVICE_ID 63 diff --git a/drivers/isdn/mISDN/core.h b/drivers/isdn/mISDN/core.h index 52695bb..6ea673f 100644 --- a/drivers/isdn/mISDN/core.h +++ b/drivers/isdn/mISDN/core.h @@ -17,6 +17,7 @@ extern struct mISDNdevice *get_mdevice(u_int); extern int get_mdevice_count(void); +extern u_int misdn_permitted_gid; /* stack status flag */ #define mISDN_STACK_ACTION_MASK 0x0000ffff diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c index e47dcb9..71f4986 100644 --- a/drivers/isdn/mISDN/socket.c +++ b/drivers/isdn/mISDN/socket.c @@ -612,6 +612,10 @@ data_sock_create(struct net *net, struct socket *sock, int protocol) { struct sock *sk; + if(!capable(CAP_SYS_ADMIN) && (misdn_permitted_gid != current_gid()) + && (!in_group_p(misdn_permitted_gid))) + return -EPERM; + if (sock->type != SOCK_DGRAM) return -ESOCKTNOSUPPORT; @@ -694,6 +698,10 @@ base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) case IMSETDEVNAME: { struct mISDN_devrename dn; + if(!capable(CAP_SYS_ADMIN) + && (misdn_permitted_gid != current_gid()) + && (!in_group_p(misdn_permitted_gid))) + return -EPERM; if (copy_from_user(&dn, (void __user *)arg, sizeof(dn))) { err = -EFAULT;