1# SPDX-License-Identifier: GPL-2.0-only
2
3# BPF interpreter that, for example, classic socket filters depend on.
4config BPF
5	bool
6	select CRYPTO_LIB_SHA1
7
8# Used by archs to tell that they support BPF JIT compiler plus which
9# flavour. Only one of the two can be selected for a specific arch since
10# eBPF JIT supersedes the cBPF JIT.
11
12# Classic BPF JIT (cBPF)
13config HAVE_CBPF_JIT
14	bool
15
16# Extended BPF JIT (eBPF)
17config HAVE_EBPF_JIT
18	bool
19
20# Used by archs to tell that they want the BPF JIT compiler enabled by
21# default for kernels that were compiled with BPF JIT support.
22config ARCH_WANT_DEFAULT_BPF_JIT
23	bool
24
25menu "BPF subsystem"
26
27config BPF_SYSCALL
28	bool "Enable bpf() system call"
29	select BPF
30	select IRQ_WORK
31	select NEED_TASKS_RCU
32	select TASKS_TRACE_RCU
33	select BINARY_PRINTF
34	select NET_SOCK_MSG if NET
35	select NET_XGRESS if NET
36	select PAGE_POOL if NET
37	default n
38	help
39	  Enable the bpf() system call that allows to manipulate BPF programs
40	  and maps via file descriptors.
41
42config BPF_JIT
43	bool "Enable BPF Just In Time compiler"
44	depends on BPF
45	depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT
46	select EXECMEM
47	help
48	  BPF programs are normally handled by a BPF interpreter. This option
49	  allows the kernel to generate native code when a program is loaded
50	  into the kernel. This will significantly speed-up processing of BPF
51	  programs.
52
53	  Note, an admin should enable this feature changing:
54	  /proc/sys/net/core/bpf_jit_enable
55	  /proc/sys/net/core/bpf_jit_harden   (optional)
56	  /proc/sys/net/core/bpf_jit_kallsyms (optional)
57
58config BPF_JIT_ALWAYS_ON
59	bool "Permanently enable BPF JIT and remove BPF interpreter"
60	depends on BPF_SYSCALL && HAVE_EBPF_JIT && BPF_JIT
61	help
62	  Enables BPF JIT and removes BPF interpreter to avoid speculative
63	  execution of BPF instructions by the interpreter.
64
65	  When CONFIG_BPF_JIT_ALWAYS_ON is enabled, /proc/sys/net/core/bpf_jit_enable
66	  is permanently set to 1 and setting any other value than that will
67	  return failure.
68
69config BPF_JIT_DEFAULT_ON
70	def_bool ARCH_WANT_DEFAULT_BPF_JIT || BPF_JIT_ALWAYS_ON
71	depends on HAVE_EBPF_JIT && BPF_JIT
72
73config BPF_UNPRIV_DEFAULT_OFF
74	bool "Disable unprivileged BPF by default"
75	default y
76	depends on BPF_SYSCALL
77	help
78	  Disables unprivileged BPF by default by setting the corresponding
79	  /proc/sys/kernel/unprivileged_bpf_disabled knob to 2. An admin can
80	  still reenable it by setting it to 0 later on, or permanently
81	  disable it by setting it to 1 (from which no other transition to
82	  0 is possible anymore).
83
84	  Unprivileged BPF could be used to exploit certain potential
85	  speculative execution side-channel vulnerabilities on unmitigated
86	  affected hardware.
87
88	  If you are unsure how to answer this question, answer Y.
89
90source "kernel/bpf/preload/Kconfig"
91
92config BPF_LSM
93	bool "Enable BPF LSM Instrumentation"
94	depends on BPF_EVENTS
95	depends on BPF_SYSCALL
96	depends on SECURITY
97	depends on BPF_JIT
98	help
99	  Enables instrumentation of the security hooks with BPF programs for
100	  implementing dynamic MAC and Audit Policies.
101
102	  If you are unsure how to answer this question, answer N.
103
104endmenu # "BPF subsystem"
105