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Release 4.15 kernel/bpf/disasm.c

Directory: kernel/bpf
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 * Copyright (c) 2016 Facebook
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 */

#include <linux/bpf.h>

#include "disasm.h"


#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)

static const char * const func_id_str[] = {
	__BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
};

#undef __BPF_FUNC_STR_FN


const char *func_id_name(int id) { BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID); if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id]) return func_id_str[id]; else return "unknown"; }

Contributors

PersonTokensPropCommitsCommitProp
Jakub Kiciński45100.00%1100.00%
Total45100.00%1100.00%

const char *const bpf_class_string[8] = { [BPF_LD] = "ld", [BPF_LDX] = "ldx", [BPF_ST] = "st", [BPF_STX] = "stx", [BPF_ALU] = "alu", [BPF_JMP] = "jmp", [BPF_RET] = "BUG", [BPF_ALU64] = "alu64", }; const char *const bpf_alu_string[16] = { [BPF_ADD >> 4] = "+=", [BPF_SUB >> 4] = "-=", [BPF_MUL >> 4] = "*=", [BPF_DIV >> 4] = "/=", [BPF_OR >> 4] = "|=", [BPF_AND >> 4] = "&=", [BPF_LSH >> 4] = "<<=", [BPF_RSH >> 4] = ">>=", [BPF_NEG >> 4] = "neg", [BPF_MOD >> 4] = "%=", [BPF_XOR >> 4] = "^=", [BPF_MOV >> 4] = "=", [BPF_ARSH >> 4] = "s>>=", [BPF_END >> 4] = "endian", }; static const char *const bpf_ldst_string[] = { [BPF_W >> 3] = "u32", [BPF_H >> 3] = "u16", [BPF_B >> 3] = "u8", [BPF_DW >> 3] = "u64", }; static const char *const bpf_jmp_string[16] = { [BPF_JA >> 4] = "jmp", [BPF_JEQ >> 4] = "==", [BPF_JGT >> 4] = ">", [BPF_JLT >> 4] = "<", [BPF_JGE >> 4] = ">=", [BPF_JLE >> 4] = "<=", [BPF_JSET >> 4] = "&", [BPF_JNE >> 4] = "!=", [BPF_JSGT >> 4] = "s>", [BPF_JSLT >> 4] = "s<", [BPF_JSGE >> 4] = "s>=", [BPF_JSLE >> 4] = "s<=", [BPF_CALL >> 4] = "call", [BPF_EXIT >> 4] = "exit", };
static void print_bpf_end_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, const struct bpf_insn *insn) { verbose(env, "(%02x) r%d = %s%d r%d\n", insn->code, insn->dst_reg, BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le", insn->imm, insn->dst_reg); }

Contributors

PersonTokensPropCommitsCommitProp
Jakub Kiciński56100.00%1100.00%
Total56100.00%1100.00%


void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, const struct bpf_insn *insn, bool allow_ptr_leaks) { u8 class = BPF_CLASS(insn->code); if (class == BPF_ALU || class == BPF_ALU64) { if (BPF_OP(insn->code) == BPF_END) { if (class == BPF_ALU64) verbose(env, "BUG_alu64_%02x\n", insn->code); else print_bpf_end_insn(verbose, env, insn); } else if (BPF_OP(insn->code) == BPF_NEG) { verbose(env, "(%02x) r%d = %s-r%d\n", insn->code, insn->dst_reg, class == BPF_ALU ? "(u32) " : "", insn->dst_reg); } else if (BPF_SRC(insn->code) == BPF_X) { verbose(env, "(%02x) %sr%d %s %sr%d\n", insn->code, class == BPF_ALU ? "(u32) " : "", insn->dst_reg, bpf_alu_string[BPF_OP(insn->code) >> 4], class == BPF_ALU ? "(u32) " : "", insn->src_reg); } else { verbose(env, "(%02x) %sr%d %s %s%d\n", insn->code, class == BPF_ALU ? "(u32) " : "", insn->dst_reg, bpf_alu_string[BPF_OP(insn->code) >> 4], class == BPF_ALU ? "(u32) " : "", insn->imm); } } else if (class == BPF_STX) { if (BPF_MODE(insn->code) == BPF_MEM) verbose(env, "(%02x) *(%s *)(r%d %+d) = r%d\n", insn->code, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->dst_reg, insn->off, insn->src_reg); else if (BPF_MODE(insn->code) == BPF_XADD) verbose(env, "(%02x) lock *(%s *)(r%d %+d) += r%d\n", insn->code, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->dst_reg, insn->off, insn->src_reg); else verbose(env, "BUG_%02x\n", insn->code); } else if (class == BPF_ST) { if (BPF_MODE(insn->code) != BPF_MEM) { verbose(env, "BUG_st_%02x\n", insn->code); return; } verbose(env, "(%02x) *(%s *)(r%d %+d) = %d\n", insn->code, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->dst_reg, insn->off, insn->imm); } else if (class == BPF_LDX) { if (BPF_MODE(insn->code) != BPF_MEM) { verbose(env, "BUG_ldx_%02x\n", insn->code); return; } verbose(env, "(%02x) r%d = *(%s *)(r%d %+d)\n", insn->code, insn->dst_reg, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->src_reg, insn->off); } else if (class == BPF_LD) { if (BPF_MODE(insn->code) == BPF_ABS) { verbose(env, "(%02x) r0 = *(%s *)skb[%d]\n", insn->code, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->imm); } else if (BPF_MODE(insn->code) == BPF_IND) { verbose(env, "(%02x) r0 = *(%s *)skb[r%d + %d]\n", insn->code, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->src_reg, insn->imm); } else if (BPF_MODE(insn->code) == BPF_IMM && BPF_SIZE(insn->code) == BPF_DW) { /* At this point, we already made sure that the second * part of the ldimm64 insn is accessible. */ u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm; bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD; if (map_ptr && !allow_ptr_leaks) imm = 0; verbose(env, "(%02x) r%d = 0x%llx\n", insn->code, insn->dst_reg, (unsigned long long)imm); } else { verbose(env, "BUG_ld_%02x\n", insn->code); return; } } else if (class == BPF_JMP) { u8 opcode = BPF_OP(insn->code); if (opcode == BPF_CALL) { verbose(env, "(%02x) call %s#%d\n", insn->code, func_id_name(insn->imm), insn->imm); } else if (insn->code == (BPF_JMP | BPF_JA)) { verbose(env, "(%02x) goto pc%+d\n", insn->code, insn->off); } else if (insn->code == (BPF_JMP | BPF_EXIT)) { verbose(env, "(%02x) exit\n", insn->code); } else if (BPF_SRC(insn->code) == BPF_X) { verbose(env, "(%02x) if r%d %s r%d goto pc%+d\n", insn->code, insn->dst_reg, bpf_jmp_string[BPF_OP(insn->code) >> 4], insn->src_reg, insn->off); } else { verbose(env, "(%02x) if r%d %s 0x%x goto pc%+d\n", insn->code, insn->dst_reg, bpf_jmp_string[BPF_OP(insn->code) >> 4], insn->imm, insn->off); } } else { verbose(env, "(%02x) %s\n", insn->code, bpf_class_string[class]); } }

Contributors

PersonTokensPropCommitsCommitProp
Jakub Kiciński899100.00%1100.00%
Total899100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Jakub Kiciński1380100.00%1100.00%
Total1380100.00%1100.00%
Directory: kernel/bpf
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