Merge 1cea68e into 2d22fd6

package/yast2-bootloader.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Fri Apr 26 12:27:34 UTC 2019 - jreidinger <jreidinger@suse.com>
+
+- renamed "smt" to "cpu_mitigations", improved naming and help
+  (bsc#1098559)
+- 4.1.24
+
 -------------------------------------------------------------------
 Mon Mar 25 15:45:54 CET 2019 - schubi@suse.de
 

package/yast2-bootloader.spec

@@ -17,7 +17,7 @@
 
 
 Name:           yast2-bootloader
-Version:        4.1.23
+Version:        4.1.24
 Release:        0
 
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build

src/autoyast-rnc/bootloader.rnc

@@ -71,7 +71,7 @@ bl_global =
     boot_extended? &
     boot_mbr? &
     stage1_dev? &
-    smt? &
+    cpu_mitigations? &
     element vgamode { text }?
   }
 
@@ -86,7 +86,7 @@ boot_root = element boot_root { "true" | "false" }
 boot_boot = element boot_boot { "true" | "false" }
 boot_extended = element boot_extended { "true" | "false" }
 boot_mbr = element boot_mbr { "true" | "false" }
-smt = element smt { "true" | "false" }
+cpu_mitigations = element cpu_mitigations { "nosmt", "auto", "off", "manual" }
 
 sections =
   element sections {

src/lib/bootloader/autoyast_converter.rb

@@ -1,6 +1,7 @@
 require "yast"
 
 require "bootloader/bootloader_factory"
+require "bootloader/cpu_mitigations"
 
 Yast.import "BootStorage"
 Yast.import "Arch"
@@ -37,7 +38,8 @@ def import(data)
         # always nil pmbr as autoyast does not support it yet,
         # so use nil to always use proposed value (bsc#1081967)
         bootloader.pmbr_action = nil
-        bootloader.smt = data["global"]["smt"] == "true" unless data["global"]["smt"].nil?
+        cpu_mitigations = data["global"]["cpu_mitigations"]
+        bootloader.cpu_mitigations = CpuMitigations.from_string(cpu_mitigations) if cpu_mitigations
         # TODO: import Initrd
 
         log.warn "autoyast profile contain sections which won't be processed" if data["sections"]
@@ -57,7 +59,7 @@ def export(config)
         global = res["global"]
         export_grub2(global, config) if config.name == "grub2"
         export_default(global, config.grub_default)
-        res["global"]["smt"] = config.smt ? "true" : "false"
+        res["global"]["cpu_mitigations"] = config.cpu_mitigations.value.to_s
         # Do not export device map as device name are very unpredictable and is used only as
         # work-around when automatic ones do not work for what-ever reasons ( it can really safe
         # your day in L3 )
@@ -79,7 +81,7 @@ def import_grub2(data, bootloader)
       end
 
       def import_default(data, default)
-        # import first kernel params as smt can later modify it
+        # import first kernel params as cpu_mitigations can later modify it
         DEFAULT_KERNEL_PARAMS_MAPPING.each do |key, method|
           val = data["global"][key]
           next unless val

src/lib/bootloader/config_dialog.rb

@@ -17,6 +17,11 @@ class ConfigDialog
     include Yast::I18n
     include Yast::UIShortcuts
 
+    # param initial_tab [:boot_code|:kernel|:bootloader] initial tab when dialog open
+    def initialize(initial_tab: :boot_code)
+      @initial_tab = initial_tab
+    end
+
     def run
       guarded_run
     rescue ::Bootloader::BrokenConfiguration, ::Bootloader::UnsupportedOption => e
@@ -63,13 +68,6 @@ def guarded_run
       end
       # F#300779: end
 
-      if BootloaderFactory.current.is_a?(NoneBootloader)
-        contents = VBox(LoaderTypeWidget.new)
-      else
-        tabs = CWM::Tabs.new(BootCodeTab.new, KernelTab.new, BootloaderTab.new)
-        contents = VBox(tabs)
-      end
-
       Yast::CWM.show(
         contents,
         caption:        _("Boot Loader Settings"),
@@ -79,5 +77,22 @@ def guarded_run
         skip_store_for: [:redraw]
       )
     end
+
+    def contents
+      return VBox(LoaderTypeWidget.new) if BootloaderFactory.current.is_a?(NoneBootloader)
+
+      boot_code_tab = BootCodeTab.new
+      kernel_tab = KernelTab.new
+      bootloader_tab = BootloaderTab.new
+      case @initial_tab
+      when :boot_code then boot_code_tab.initial = true
+      when :kernel then kernel_tab.initial = true
+      when :bootloader then bootloader_tab.initial = true
+      else
+        raise "unknown initial tab #{@initial_tab.inspect}"
+      end
+
+      VBox(CWM::Tabs.new(boot_code_tab, kernel_tab, bootloader_tab))
+    end
   end
 end

src/lib/bootloader/cpu_mitigations.rb

@@ -0,0 +1,75 @@
+require "yast"
+
+require "cfa/matcher"
+require "cfa/placer"
+
+module Bootloader
+  # Specialized class to handle CPU mitigation settings.
+  # @see https://www.suse.com/support/kb/doc/?id=7023836
+  class CpuMitigations
+    include Yast::Logger
+    include Yast::I18n
+    extend Yast::I18n
+    KERNEL_MAPPING = {
+      nosmt:  "auto,nosmt",
+      auto:   "auto",
+      off:    "off",
+      manual: nil
+    }.freeze
+
+    HUMAN_MAPPING = {
+      nosmt:  N_("Auto + No SMT"),
+      auto:   N_("Auto"),
+      off:    N_("Off"),
+      manual: N_("Manually")
+    }.freeze
+
+    attr_reader :value
+
+    def initialize(value)
+      textdomain "bootloader"
+
+      @value = value
+    end
+
+    # Note: order of ALL is used also in UI as order of combobox.
+    ALL = KERNEL_MAPPING.keys.map { |k| CpuMitigations.new(k) }
+    DEFAULT = CpuMitigations.new(:auto)
+
+    def self.from_kernel_params(kernel_params)
+      log.info "kernel params #{kernel_params.inspect}"
+      param = kernel_params.parameter("mitigations")
+      log.info "mitigation param #{param.inspect}"
+      param = nil if param == false
+      reverse_mapping = KERNEL_MAPPING.invert
+      raise "Unknown mitigations value #{param.inspect}" if !reverse_mapping.key?(param)
+
+      new(reverse_mapping[param])
+    end
+
+    def self.from_string(string)
+      raise "Unknown mitigations value #{string.inspect}" unless KERNEL_MAPPING.key?(string.to_sym)
+
+      new(string.to_sym)
+    end
+
+    def to_human_string
+      _(HUMAN_MAPPING[value])
+    end
+
+    def kernel_value
+      KERNEL_MAPPING[value] or raise "Invalid value #{value.inspect}"
+    end
+
+    def modify_kernel_params(kernel_params)
+      matcher = CFA::Matcher.new(key: "mitigations")
+
+      kernel_params.remove_parameter(matcher)
+      if value != :manual
+        # TODO: fix cfa_grub2 with replace placer
+        kernel_params.add_parameter("mitigations", kernel_value)
+        log.info "replacing old config with #{kernel_value}: #{kernel_params.inspect}"
+      end
+    end
+  end
+end

src/lib/bootloader/grub2_widgets.rb

@@ -3,6 +3,7 @@
 require "bootloader/generic_widgets"
 require "bootloader/device_map_dialog"
 require "bootloader/serial_console"
+require "bootloader/cpu_mitigations"
 require "cfa/matcher"
 
 Yast.import "BootStorage"
@@ -113,30 +114,53 @@ def store
   end
 
   # Represents decision if smt is enabled
-  class Smt < CWM::CheckBox
+  class CpuMitigationsWidget < CWM::ComboBox
     include Grub2Widget
 
     def initialize
       textdomain "bootloader"
     end
 
     def label
-      _("Disable Simultaneous &Multithreading")
+      _("CPU Mitigations")
+    end
+
+    def items
+      ::Bootloader::CpuMitigations::ALL.map do |m|
+        [m.value, m.to_human_string]
+      end
     end
 
     def help
       _(
-        "<p><b>Disable Simultaneous Multithreading</b><br>\n" \
-          "To disable sharing physical cores by more virtual ones."
+        "<p><b>CPU Mitigations</b><br>\n" \
+          "The option selects which default settings should be used for CPU " \
+          "side channels mitigations. A highlevel description is on our Technical Information " \
+          "Document TID 7023836. Following options are available:<ul>" \
+          "<li><b>Auto</b>: This option enables all the mitigations needed for your CPU model. " \
+          "This setting can impact performance to some degree, depending on CPU model and " \
+          "workload. It provides all security mitigations, but it does not protect against " \
+          "cross-CPU thread attacks.</li>" \
+          "<li><b>Auto + No SMT</b>: This option enables all the above mitigations in \"Auto\", " \
+          "and also disables Simultaneous Multithreading to avoid side channel attacks across " \
+          "multiple CPU threads. This setting can further impact performance, depending on your " \
+          "workload. This setting provides the full set of available security mitigations.</li>" \
+          "<li><b>Off</b>: All CPU Mitigations are disabled. This setting has no performance " \
+          "impact, but side channel attacks against your CPU are possible, depending on CPU " \
+          "model.</li>" \
+          "<li><b>Manual</b>: This setting does not specify a mitigation level and leaves " \
+          "this to be the kernel default. The administrator can add other mitigations options " \
+          "in the <i>kernel command line</i> widget." \
+          "All CPU mitigation specific options can be set manually.</li></ul></p>"
       )
     end
 
     def init
-      self.value = !grub2.smt
+      self.value = grub2.cpu_mitigations.value
     end
 
     def store
-      grub2.smt = !value
+      grub2.cpu_mitigations = ::Bootloader::CpuMitigations.new(value)
     end
   end
 
@@ -240,7 +264,7 @@ def help
     end
 
     def init
-      self.value = grub_default.kernel_params.serialize.gsub(/nosmt/, "")
+      self.value = grub_default.kernel_params.serialize.gsub(/mitigations=\S+/, "")
     end
 
     def store
@@ -872,11 +896,10 @@ def label
 
     def contents
       console_widget = Yast::Arch.s390 ? CWM::Empty.new("console") : ConsoleWidget.new
-      smt_widget = Yast::Arch.x86_64 ? MarginBox(1, 0.5, Smt.new) : CWM::Empty.new("smt")
       VBox(
         VSpacing(1),
         MarginBox(1, 0.5, KernelAppendWidget.new),
-        Left(smt_widget),
+        MarginBox(1, 0.5, Left(CpuMitigationsWidget.new)),
         MarginBox(1, 0.5, console_widget),
         VStretch()
       )
@@ -887,10 +910,6 @@ def contents
   class BootCodeTab < CWM::Tab
     include Grub2Widget
 
-    def initialize
-      self.initial = true
-    end
-
     def label
       textdomain "bootloader"
 

src/lib/bootloader/grub2base.rb

@@ -54,7 +54,7 @@ def initialize
       @grub_default = ::CFA::Grub2::Default.new
       @sections = ::Bootloader::Sections.new
       @pmbr_action = :nothing
-      @smt = nil # nil means not set explicitly, otherwise boolean
+      @explicit_cpu_mitigations = false
     end
 
     # general functions
@@ -75,24 +75,18 @@ def pmbr_setup(*devices)
       end
     end
 
-    def smt
-      !grub_default.kernel_params.parameter("nosmt")
+    def cpu_mitigations
+      CpuMitigations.from_kernel_params(grub_default.kernel_params)
     end
 
-    def explicit_smt
-      @smt
+    def explicit_cpu_mitigations
+      @explicit_cpu_mitigations ? cpu_mitigations : nil
     end
 
-    def smt=(value)
-      log.info "setting smt to #{value}"
-      @smt = value
-
-      if value
-        matcher = CFA::Matcher.new(key: "nosmt")
-        grub_default.kernel_params.remove_parameter(matcher)
-      elsif !grub_default.kernel_params.parameter("nosmt")
-        grub_default.kernel_params.add_parameter("nosmt", true)
-      end
+    def cpu_mitigations=(value)
+      log.info "setting mitigations to #{value}"
+      @explicit_cpu_mitigations = true
+      value.modify_kernel_params(grub_default.kernel_params)
     end
 
     def read
@@ -219,28 +213,37 @@ def merge_grub_default(other)
       log.info "before merge other #{other_default.inspect}"
 
       KERNEL_FLAVORS_METHODS.each do |method|
-        other_params = other_default.public_send(method)
-        default_params = default.public_send(method)
-        next if other_params.empty?
-
-        default_serialize = default_params.serialize
-        # handle specially noresume as it should lead to remove all other resume
-        default_serialize.gsub!(/resume=\S+/, "") if other_params.parameter("noresume")
-
-        new_kernel_params = default_serialize + " " + other_params.serialize
-
-        default_params.replace(new_kernel_params)
+        merge_kernel_params(method, other_default)
       end
 
       merge_attributes(default, other_default)
 
-      # explicitly set smt
-      self.smt = other.explicit_smt unless other.explicit_smt.nil?
-      log.info "smt after merge #{smt}"
+      # explicitly set mitigations means overwrite of our
+      if other.explicit_cpu_mitigations
+        log.info "merging cpu_mitigations"
+        self.cpu_mitigations = other.cpu_mitigations
+      end
+      log.info "mitigations after merge #{cpu_mitigations}"
 
       log.info "after merge default #{default.inspect}"
     end
 
+    def merge_kernel_params(method, other_default)
+      other_params = other_default.public_send(method)
+      default_params = grub_default.public_send(method)
+      return if other_params.empty?
+
+      default_serialize = default_params.serialize
+      # handle specially noresume as it should lead to remove all other resume
+      default_serialize.gsub!(/resume=\S+/, "") if other_params.parameter("noresume")
+      # prevent double cpu_mitigations params
+      default_serialize.gsub!(/mitigations=\S+/, "") if other_params.parameter("mitigations")
+
+      new_kernel_params = default_serialize + " " + other_params.serialize
+
+      default_params.replace(new_kernel_params)
+    end
+
     def merge_attributes(default, other)
       # string attributes
       [:serial_console, :timeout, :hidden_timeout, :distributor,
@@ -338,4 +341,5 @@ def propose_encrypted
       grub_default.cryptodisk.value = !!Yast::BootStorage.encrypted_boot?
     end
   end
+  # rubocop:enable Metrics/ClassLength
 end