From 5e1fccc0bfac4946932b36e4535c03957d35113d Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 16 Nov 2012 03:03:04 +0000 Subject: net: Allow userns root control of the core of the network stack. Allow an unpriviled user who has created a user namespace, and then created a network namespace to effectively use the new network namespace, by reducing capable(CAP_NET_ADMIN) and capable(CAP_NET_RAW) calls to be ns_capable(net->user_ns, CAP_NET_ADMIN), or capable(net->user_ns, CAP_NET_RAW) calls. Settings that merely control a single network device are allowed. Either the network device is a logical network device where restrictions make no difference or the network device is hardware NIC that has been explicity moved from the initial network namespace. In general policy and network stack state changes are allowed while resource control is left unchanged. Allow ethtool ioctls. Allow binding to network devices. Allow setting the socket mark. Allow setting the socket priority. Allow setting the network device alias via sysfs. Allow setting the mtu via sysfs. Allow changing the network device flags via sysfs. Allow setting the network device group via sysfs. Allow the following network device ioctls. SIOCGMIIPHY SIOCGMIIREG SIOCSIFNAME SIOCSIFFLAGS SIOCSIFMETRIC SIOCSIFMTU SIOCSIFHWADDR SIOCSIFSLAVE SIOCADDMULTI SIOCDELMULTI SIOCSIFHWBROADCAST SIOCSMIIREG SIOCBONDENSLAVE SIOCBONDRELEASE SIOCBONDSETHWADDR SIOCBONDCHANGEACTIVE SIOCBRADDIF SIOCBRDELIF SIOCSHWTSTAMP Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller --- net/core/sock.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 06286006a2c..d4f7b58b386 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -515,7 +515,7 @@ static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen) /* Sorry... */ ret = -EPERM; - if (!capable(CAP_NET_RAW)) + if (!ns_capable(net->user_ns, CAP_NET_RAW)) goto out; ret = -EINVAL; @@ -696,7 +696,8 @@ set_rcvbuf: break; case SO_PRIORITY: - if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN)) + if ((val >= 0 && val <= 6) || + ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) sk->sk_priority = val; else ret = -EPERM; @@ -813,7 +814,7 @@ set_rcvbuf: clear_bit(SOCK_PASSSEC, &sock->flags); break; case SO_MARK: - if (!capable(CAP_NET_ADMIN)) + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) ret = -EPERM; else sk->sk_mark = val; -- cgit v1.2.3