linux/samples/bpf/test_verifier.c

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/*
* Testsuite for eBPF verifier
*
* Copyright (c) 2014 PLUMgrid, http://plumgrid.com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#include <stdio.h>
#include <unistd.h>
#include <linux/bpf.h>
#include <errno.h>
#include <linux/unistd.h>
#include <string.h>
#include <linux/filter.h>
#include <stddef.h>
#include "libbpf.h"
#define MAX_INSNS 512
#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
struct bpf_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
int fixup[32];
const char *errstr;
enum {
ACCEPT,
REJECT
} result;
};
static struct bpf_test tests[] = {
{
"add+sub+mul",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 1),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 2),
BPF_MOV64_IMM(BPF_REG_2, 3),
BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_2),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -1),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_1, 3),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"unreachable",
.insns = {
BPF_EXIT_INSN(),
BPF_EXIT_INSN(),
},
.errstr = "unreachable",
.result = REJECT,
},
{
"unreachable2",
.insns = {
BPF_JMP_IMM(BPF_JA, 0, 0, 1),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "unreachable",
.result = REJECT,
},
{
"out of range jump",
.insns = {
BPF_JMP_IMM(BPF_JA, 0, 0, 1),
BPF_EXIT_INSN(),
},
.errstr = "jump out of range",
.result = REJECT,
},
{
"out of range jump2",
.insns = {
BPF_JMP_IMM(BPF_JA, 0, 0, -2),
BPF_EXIT_INSN(),
},
.errstr = "jump out of range",
.result = REJECT,
},
{
"test1 ld_imm64",
.insns = {
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_MOV64_IMM(BPF_REG_0, 2),
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_LD_IMM insn",
.result = REJECT,
},
{
"test2 ld_imm64",
.insns = {
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_LD_IMM insn",
.result = REJECT,
},
{
"test3 ld_imm64",
.insns = {
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 0),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 0),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_LD_IMM64(BPF_REG_0, 1),
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_ld_imm64 insn",
.result = REJECT,
},
{
"test4 ld_imm64",
.insns = {
BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_ld_imm64 insn",
.result = REJECT,
},
{
"test5 ld_imm64",
.insns = {
BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, 0, 0, 0, 0),
},
.errstr = "invalid bpf_ld_imm64 insn",
.result = REJECT,
},
{
"no bpf_exit",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_0, BPF_REG_2),
},
.errstr = "jump out of range",
.result = REJECT,
},
{
"loop (back-edge)",
.insns = {
BPF_JMP_IMM(BPF_JA, 0, 0, -1),
BPF_EXIT_INSN(),
},
.errstr = "back-edge",
.result = REJECT,
},
{
"loop2 (back-edge)",
.insns = {
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_3, BPF_REG_0),
BPF_JMP_IMM(BPF_JA, 0, 0, -4),
BPF_EXIT_INSN(),
},
.errstr = "back-edge",
.result = REJECT,
},
{
"conditional loop",
.insns = {
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_3, BPF_REG_0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, -3),
BPF_EXIT_INSN(),
},
.errstr = "back-edge",
.result = REJECT,
},
{
"read uninitialized register",
.insns = {
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_EXIT_INSN(),
},
.errstr = "R2 !read_ok",
.result = REJECT,
},
{
"read invalid register",
.insns = {
BPF_MOV64_REG(BPF_REG_0, -1),
BPF_EXIT_INSN(),
},
.errstr = "R15 is invalid",
.result = REJECT,
},
{
"program doesn't init R0 before exit",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_1),
BPF_EXIT_INSN(),
},
.errstr = "R0 !read_ok",
.result = REJECT,
},
{
"program doesn't init R0 before exit in all branches",
.insns = {
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 2),
BPF_EXIT_INSN(),
},
.errstr = "R0 !read_ok",
.result = REJECT,
},
{
"stack out of bounds",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, 8, 0),
BPF_EXIT_INSN(),
},
.errstr = "invalid stack",
.result = REJECT,
},
{
"invalid call insn1",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL | BPF_X, 0, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "BPF_CALL uses reserved",
.result = REJECT,
},
{
"invalid call insn2",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 1, 0),
BPF_EXIT_INSN(),
},
.errstr = "BPF_CALL uses reserved",
.result = REJECT,
},
{
"invalid function call",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, 1234567),
BPF_EXIT_INSN(),
},
.errstr = "invalid func 1234567",
.result = REJECT,
},
{
"uninitialized stack1",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_EXIT_INSN(),
},
.fixup = {2},
.errstr = "invalid indirect read from stack",
.result = REJECT,
},
{
"uninitialized stack2",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -8),
BPF_EXIT_INSN(),
},
.errstr = "invalid read from stack",
.result = REJECT,
},
{
"check valid spill/fill",
.insns = {
/* spill R1(ctx) into stack */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
/* fill it back into R2 */
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -8),
/* should be able to access R0 = *(R2 + 8) */
/* BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 8), */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"check corrupted spill/fill",
.insns = {
/* spill R1(ctx) into stack */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
/* mess up with R1 pointer on stack */
BPF_ST_MEM(BPF_B, BPF_REG_10, -7, 0x23),
/* fill back into R0 should fail */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_EXIT_INSN(),
},
.errstr = "corrupted spill",
.result = REJECT,
},
{
"invalid src register in STX",
.insns = {
BPF_STX_MEM(BPF_B, BPF_REG_10, -1, -1),
BPF_EXIT_INSN(),
},
.errstr = "R15 is invalid",
.result = REJECT,
},
{
"invalid dst register in STX",
.insns = {
BPF_STX_MEM(BPF_B, 14, BPF_REG_10, -1),
BPF_EXIT_INSN(),
},
.errstr = "R14 is invalid",
.result = REJECT,
},
{
"invalid dst register in ST",
.insns = {
BPF_ST_MEM(BPF_B, 14, -1, -1),
BPF_EXIT_INSN(),
},
.errstr = "R14 is invalid",
.result = REJECT,
},
{
"invalid src register in LDX",
.insns = {
BPF_LDX_MEM(BPF_B, BPF_REG_0, 12, 0),
BPF_EXIT_INSN(),
},
.errstr = "R12 is invalid",
.result = REJECT,
},
{
"invalid dst register in LDX",
.insns = {
BPF_LDX_MEM(BPF_B, 11, BPF_REG_1, 0),
BPF_EXIT_INSN(),
},
.errstr = "R11 is invalid",
.result = REJECT,
},
{
"junk insn",
.insns = {
BPF_RAW_INSN(0, 0, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_LD_IMM",
.result = REJECT,
},
{
"junk insn2",
.insns = {
BPF_RAW_INSN(1, 0, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "BPF_LDX uses reserved fields",
.result = REJECT,
},
{
"junk insn3",
.insns = {
BPF_RAW_INSN(-1, 0, 0, 0, 0),
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_ALU opcode f0",
.result = REJECT,
},
{
"junk insn4",
.insns = {
BPF_RAW_INSN(-1, -1, -1, -1, -1),
BPF_EXIT_INSN(),
},
.errstr = "invalid BPF_ALU opcode f0",
.result = REJECT,
},
{
"junk insn5",
.insns = {
BPF_RAW_INSN(0x7f, -1, -1, -1, -1),
BPF_EXIT_INSN(),
},
.errstr = "BPF_ALU uses reserved fields",
.result = REJECT,
},
{
"misaligned read from stack",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -4),
BPF_EXIT_INSN(),
},
.errstr = "misaligned access",
.result = REJECT,
},
{
"invalid map_fd for function call",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.errstr = "fd 0 is not pointing to valid bpf_map",
.result = REJECT,
},
{
"don't check return value before access",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
.fixup = {3},
.errstr = "R0 invalid mem access 'map_value_or_null'",
.result = REJECT,
},
{
"access memory with incorrect alignment",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),
BPF_EXIT_INSN(),
},
.fixup = {3},
.errstr = "misaligned access",
.result = REJECT,
},
{
"sometimes access memory with incorrect alignment",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
},
.fixup = {3},
.errstr = "R0 invalid mem access",
.result = REJECT,
},
{
"jump test 1",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, -8),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -16, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 2, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -16, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 4, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 5, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -32, 5),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"jump test 2",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 0),
BPF_JMP_IMM(BPF_JA, 0, 0, 14),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -16, 0),
BPF_JMP_IMM(BPF_JA, 0, 0, 11),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 2, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -32, 0),
BPF_JMP_IMM(BPF_JA, 0, 0, 8),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -40, 0),
BPF_JMP_IMM(BPF_JA, 0, 0, 5),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 4, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -48, 0),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 5, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -56, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"jump test 3",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 19),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -16, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -16),
BPF_JMP_IMM(BPF_JA, 0, 0, 15),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 2, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -32, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -32),
BPF_JMP_IMM(BPF_JA, 0, 0, 11),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -40, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -40),
BPF_JMP_IMM(BPF_JA, 0, 0, 7),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 4, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -48, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -48),
BPF_JMP_IMM(BPF_JA, 0, 0, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 5, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -56, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -56),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.fixup = {24},
.result = ACCEPT,
},
{
"jump test 4",
.insns = {
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 1),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 2),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 3),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"jump test 5",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"access skb fields ok",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, len)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, mark)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, pkt_type)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, queue_mapping)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 0),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, protocol)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 0),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, vlan_present)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 0),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, vlan_tci)),
BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"access skb fields bad1",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, -4),
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
.result = REJECT,
},
{
"access skb fields bad2",
.insns = {
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 9),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, pkt_type)),
BPF_EXIT_INSN(),
},
.fixup = {4},
.errstr = "different pointers",
.result = REJECT,
},
{
"access skb fields bad3",
.insns = {
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, pkt_type)),
BPF_EXIT_INSN(),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_JMP_IMM(BPF_JA, 0, 0, -12),
},
.fixup = {6},
.errstr = "different pointers",
.result = REJECT,
},
{
"access skb fields bad4",
.insns = {
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 3),
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1,
offsetof(struct __sk_buff, len)),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_JMP_IMM(BPF_JA, 0, 0, -13),
},
.fixup = {7},
.errstr = "different pointers",
.result = REJECT,
},
};
static int probe_filter_length(struct bpf_insn *fp)
{
int len = 0;
for (len = MAX_INSNS - 1; len > 0; --len)
if (fp[len].code != 0 || fp[len].imm != 0)
break;
return len + 1;
}
static int create_map(void)
{
long long key, value = 0;
int map_fd;
map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
if (map_fd < 0) {
printf("failed to create map '%s'\n", strerror(errno));
}
return map_fd;
}
static int test(void)
{
int prog_fd, i, pass_cnt = 0, err_cnt = 0;
for (i = 0; i < ARRAY_SIZE(tests); i++) {
struct bpf_insn *prog = tests[i].insns;
int prog_len = probe_filter_length(prog);
int *fixup = tests[i].fixup;
int map_fd = -1;
if (*fixup) {
map_fd = create_map();
do {
prog[*fixup].imm = map_fd;
fixup++;
} while (*fixup);
}
printf("#%d %s ", i, tests[i].descr);
prog_fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, prog,
prog_len * sizeof(struct bpf_insn),
samples/bpf: Add simple non-portable kprobe filter example tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-26 03:49:23 +08:00
"GPL", 0);
if (tests[i].result == ACCEPT) {
if (prog_fd < 0) {
printf("FAIL\nfailed to load prog '%s'\n",
strerror(errno));
printf("%s", bpf_log_buf);
err_cnt++;
goto fail;
}
} else {
if (prog_fd >= 0) {
printf("FAIL\nunexpected success to load\n");
printf("%s", bpf_log_buf);
err_cnt++;
goto fail;
}
if (strstr(bpf_log_buf, tests[i].errstr) == 0) {
printf("FAIL\nunexpected error message: %s",
bpf_log_buf);
err_cnt++;
goto fail;
}
}
pass_cnt++;
printf("OK\n");
fail:
if (map_fd >= 0)
close(map_fd);
close(prog_fd);
}
printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, err_cnt);
return 0;
}
int main(void)
{
return test();
}