On Thu, Jan 12, 2017 at 06:39:57AM -0800, Eric Dumazet wrote: > On Wed, 2017-01-11 at 22:52 -0800, Krister Johansen wrote: > > Add net.ipv4.ip_unprotected_port_start, which is a per namespace sysctl > > that denotes the first unprotected inet port in the namespace. To > > disable all protected ports set this to zero. It also checks for > > overlap with the local port range. The protected and local range may > > not overlap. > > > > The use case for this change is to allow containerized processes to bind > > to priviliged ports, but prevent them from ever being allowed to modify > > their container's network configuration. The latter is accomplished by > > ensuring that the network namespace is not a child of the user > > namespace. This modification was needed to allow the container manager > > to disable a namespace's priviliged port restrictions without exposing > > control of the network namespace to processes in the user namespace. > > > > Signed-off-by: Krister Johansen <k...@templeofstupid.com> > > --- > > include/net/ip.h | 10 +++++++++ > > include/net/netns/ipv4.h | 1 + > > net/ipv4/af_inet.c | 5 ++++- > > net/ipv4/sysctl_net_ipv4.c | 50 > > +++++++++++++++++++++++++++++++++++++++++- > > net/ipv6/af_inet6.c | 3 ++- > > net/netfilter/ipvs/ip_vs_ctl.c | 7 +++--- > > net/sctp/socket.c | 10 +++++---- > > security/selinux/hooks.c | 3 ++- > > Adding a new sysctl without documentation is generally not accepted. > > Please take a look at Documentation/networking/ip-sysctl.txt
Thanks for catching this. I'll add an entry to the documentation. > BTW, sticking to 'unprivileged' ports might be better than 'unprotected' > which is vague. I don't have a strong preference about the naming. I'd be happy to change it to 'unprivileged' instead. -K
