Andrew Rynhard ca35b85300 refactor: improve installation reliability
This change aims to make installations more unified and reliable. It
introduces the concept of a mountpoint manager that is capable of
mounting, unmounting, and moving a set of mountpoints in the correct
order.

Signed-off-by: Andrew Rynhard <andrew@andrewrynhard.com>
2019-08-01 11:44:40 -07:00

92 lines
2.3 KiB
Go

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package kspp
import (
"github.com/hashicorp/go-multierror"
"github.com/pkg/errors"
"github.com/talos-systems/talos/internal/pkg/kernel"
"github.com/talos-systems/talos/internal/pkg/kernel/sysctl"
)
var (
// RequiredKSPPKernelParameters is the set of kernel parameters required to
// satisfy the KSPP.
// # TODO(andrewrynhard): Add slub_debug=P. See https://github.com/talos-systems/talos/pull/157.
RequiredKSPPKernelParameters = kernel.Parameters{
kernel.NewParameter("page_poison").Append("1"),
kernel.NewParameter("slab_nomerge").Append(""),
kernel.NewParameter("pti").Append("on"),
}
)
// EnforceKSPPKernelParameters verifies that all required KSPP kernel
// parameters are present with the right value.
func EnforceKSPPKernelParameters() error {
var result *multierror.Error
for _, values := range RequiredKSPPKernelParameters {
var val *string
if val = kernel.ProcCmdline().Get(values.Key()).First(); val == nil {
result = multierror.Append(result, errors.Errorf("KSPP kernel parameter %s is required", values.Key()))
continue
}
expected := values.First()
if *val != *expected {
result = multierror.Append(result, errors.Errorf("KSPP kernel parameter %s was found with value %s, expected %s", values.Key(), *val, *expected))
}
}
return result.ErrorOrNil()
}
// EnforceKSPPSysctls verifies that all required KSPP kernel sysctls are set
// with the right value.
func EnforceKSPPSysctls() (err error) {
props := []*sysctl.SystemProperty{
{
Key: "kernel.kptr_restrict",
Value: "1",
},
{
Key: "kernel.dmesg_restrict",
Value: "1",
},
{
Key: "kernel.perf_event_paranoid",
Value: "3",
},
// We can skip this sysctl because CONFIG_KEXEC is not set.
// {
// Key: "kernel.kexec_load_disabled",
// Value: "1",
// },
{
Key: "kernel.yama.ptrace_scope",
Value: "1",
},
{
Key: "user.max_user_namespaces",
Value: "0",
},
{
Key: "kernel.unprivileged_bpf_disabled",
Value: "1",
},
{
Key: "net.core.bpf_jit_harden",
Value: "2",
},
}
for _, prop := range props {
if err = sysctl.WriteSystemProperty(prop); err != nil {
return
}
}
return nil
}