kernel/bpf/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0-only
   2
   3 # BPF interpreter that, for example, classic socket filters depend on.
   4 config BPF
   5         bool
   6
   7 # Used by archs to tell that they support BPF JIT compiler plus which
   8 # flavour. Only one of the two can be selected for a specific arch since
   9 # eBPF JIT supersedes the cBPF JIT.
  10
  11 # Classic BPF JIT (cBPF)
  12 config HAVE_CBPF_JIT
  13         bool
  14
  15 # Extended BPF JIT (eBPF)
  16 config HAVE_EBPF_JIT
  17         bool
  18
  19 # Used by archs to tell that they want the BPF JIT compiler enabled by
  20 # default for kernels that were compiled with BPF JIT support.
  21 config ARCH_WANT_DEFAULT_BPF_JIT
  22         bool
  23
  24 menu "BPF subsystem"
  25
  26 config BPF_SYSCALL
  27         bool "Enable bpf() system call"
  28         select BPF
  29         select IRQ_WORK
  30         select TASKS_TRACE_RCU
  31         select BINARY_PRINTF
  32         select NET_SOCK_MSG if NET
  33         default n
  34         help
  35           Enable the bpf() system call that allows to manipulate BPF programs
  36           and maps via file descriptors.
  37
  38 config BPF_JIT
  39         bool "Enable BPF Just In Time compiler"
  40         depends on BPF
  41         depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT
  42         depends on MODULES
  43         help
  44           BPF programs are normally handled by a BPF interpreter. This option
  45           allows the kernel to generate native code when a program is loaded
  46           into the kernel. This will significantly speed-up processing of BPF
  47           programs.
  48
  49           Note, an admin should enable this feature changing:
  50           /proc/sys/net/core/bpf_jit_enable
  51           /proc/sys/net/core/bpf_jit_harden   (optional)
  52           /proc/sys/net/core/bpf_jit_kallsyms (optional)
  53
  54 config BPF_JIT_ALWAYS_ON
  55         bool "Permanently enable BPF JIT and remove BPF interpreter"
  56         depends on BPF_SYSCALL && HAVE_EBPF_JIT && BPF_JIT
  57         help
  58           Enables BPF JIT and removes BPF interpreter to avoid speculative
  59           execution of BPF instructions by the interpreter.
  60
  61 config BPF_JIT_DEFAULT_ON
  62         def_bool ARCH_WANT_DEFAULT_BPF_JIT || BPF_JIT_ALWAYS_ON
  63         depends on HAVE_EBPF_JIT && BPF_JIT
  64
  65 config BPF_UNPRIV_DEFAULT_OFF
  66         bool "Disable unprivileged BPF by default"
  67         depends on BPF_SYSCALL
  68         help
  69           Disables unprivileged BPF by default by setting the corresponding
  70           /proc/sys/kernel/unprivileged_bpf_disabled knob to 2. An admin can
  71           still reenable it by setting it to 0 later on, or permanently
  72           disable it by setting it to 1 (from which no other transition to
  73           0 is possible anymore).
  74
  75 source "kernel/bpf/preload/Kconfig"
  76
  77 config BPF_LSM
  78         bool "Enable BPF LSM Instrumentation"
  79         depends on BPF_EVENTS
  80         depends on BPF_SYSCALL
  81         depends on SECURITY
  82         depends on BPF_JIT
  83         help
  84           Enables instrumentation of the security hooks with BPF programs for
  85           implementing dynamic MAC and Audit Policies.
  86
  87           If you are unsure how to answer this question, answer N.
  88
  89 endmenu # "BPF subsystem"