Hello, On Thu, 18 Apr 2024, Alexander Mikhalitsyn wrote: > Let's make all IPVS sysctls writtable even when > network namespace is owned by non-initial user namespace. > > Let's make a few sysctls to be read-only for non-privileged users: > - sync_qlen_max > - sync_sock_size > - run_estimation > - est_cpulist > - est_nice > > I'm trying to be conservative with this to prevent > introducing any security issues in there. Maybe, > we can allow more sysctls to be writable, but let's > do this on-demand and when we see real use-case. > > This patch is motivated by user request in the LXC > project [1]. Having this can help with running some > Kubernetes [2] or Docker Swarm [3] workloads inside the system > containers. > > Link: https://github.com/lxc/lxc/issues/4278 [1] > Link: https://github.com/kubernetes/kubernetes/blob/b722d017a34b300a2284b890448e5a605f21d01e/pkg/proxy/ipvs/proxier.go#L103 [2] > Link: https://github.com/moby/libnetwork/blob/3797618f9a38372e8107d8c06f6ae199e1133ae8/osl/namespace_linux.go#L682 [3] > > Cc: Stéphane Graber <stgraber@xxxxxxxxxxxx> > Cc: Christian Brauner <brauner@xxxxxxxxxx> > Cc: Julian Anastasov <ja@xxxxxx> > Cc: Simon Horman <horms@xxxxxxxxxxxx> > Cc: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> > Cc: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx> > Cc: Florian Westphal <fw@xxxxxxxxx> > Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@xxxxxxxxxxxxx> > --- > net/netfilter/ipvs/ip_vs_ctl.c | 21 +++++++++++++++------ > 1 file changed, 15 insertions(+), 6 deletions(-) > > diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c > index 32be24f0d4e4..c3ba71aa2654 100644 > --- a/net/netfilter/ipvs/ip_vs_ctl.c > +++ b/net/netfilter/ipvs/ip_vs_ctl.c ... > @@ -4284,12 +4285,6 @@ static int __net_init ip_vs_control_net_init_sysctl(struct netns_ipvs *ipvs) > tbl = kmemdup(vs_vars, sizeof(vs_vars), GFP_KERNEL); > if (tbl == NULL) > return -ENOMEM; > - > - /* Don't export sysctls to unprivileged users */ > - if (net->user_ns != &init_user_ns) { > - tbl[0].procname = NULL; > - ctl_table_size = 0; > - } > } else > tbl = vs_vars; > /* Initialize sysctl defaults */ Sorry but you have to send v4 because above if-block was changed with net-next commit 635470eb0aa7 from today... Regards -- Julian Anastasov <ja@xxxxxx>
