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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2015-2017 Josh Poimboeuf <jpoimboe@redhat.com>4 */5 6#include <subcmd/parse-options.h>7#include <string.h>8#include <stdlib.h>9#include <objtool/builtin.h>10#include <objtool/objtool.h>11 12#define ERROR(format, ...) \13 fprintf(stderr, \14 "error: objtool: " format "\n", \15 ##__VA_ARGS__)16 17struct opts opts;18 19static const char * const check_usage[] = {20 "objtool <actions> [<options>] file.o",21 NULL,22};23 24static const char * const env_usage[] = {25 "OBJTOOL_ARGS=\"<options>\"",26 NULL,27};28 29static int parse_dump(const struct option *opt, const char *str, int unset)30{31 if (!str || !strcmp(str, "orc")) {32 opts.dump_orc = true;33 return 0;34 }35 36 return -1;37}38 39static int parse_hacks(const struct option *opt, const char *str, int unset)40{41 bool found = false;42 43 /*44 * Use strstr() as a lazy method of checking for comma-separated45 * options.46 *47 * No string provided == enable all options.48 */49 50 if (!str || strstr(str, "jump_label")) {51 opts.hack_jump_label = true;52 found = true;53 }54 55 if (!str || strstr(str, "noinstr")) {56 opts.hack_noinstr = true;57 found = true;58 }59 60 if (!str || strstr(str, "skylake")) {61 opts.hack_skylake = true;62 found = true;63 }64 65 return found ? 0 : -1;66}67 68static const struct option check_options[] = {69 OPT_GROUP("Actions:"),70 OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr,skylake", "patch toolchain bugs/limitations", parse_hacks),71 OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"),72 OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"),73 OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"),74 OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"),75 OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"),76 OPT_BOOLEAN(0, "rethunk", &opts.rethunk, "validate and annotate rethunk usage"),77 OPT_BOOLEAN(0, "unret", &opts.unret, "validate entry unret placement"),78 OPT_INTEGER(0, "prefix", &opts.prefix, "generate prefix symbols"),79 OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"),80 OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"),81 OPT_BOOLEAN('t', "static-call", &opts.static_call, "annotate static calls"),82 OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"),83 OPT_BOOLEAN(0 , "cfi", &opts.cfi, "annotate kernel control flow integrity (kCFI) function preambles"),84 OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump),85 86 OPT_GROUP("Options:"),87 OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"),88 OPT_BOOLEAN(0, "backup", &opts.backup, "create .orig files before modification"),89 OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"),90 OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"),91 OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"),92 OPT_BOOLEAN(0, "mnop", &opts.mnop, "nop out mcount call sites"),93 OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"),94 OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"),95 OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"),96 OPT_BOOLEAN('v', "verbose", &opts.verbose, "verbose warnings"),97 98 OPT_END(),99};100 101int cmd_parse_options(int argc, const char **argv, const char * const usage[])102{103 const char *envv[16] = { };104 char *env;105 int envc;106 107 env = getenv("OBJTOOL_ARGS");108 if (env) {109 envv[0] = "OBJTOOL_ARGS";110 for (envc = 1; envc < ARRAY_SIZE(envv); ) {111 envv[envc++] = env;112 env = strchr(env, ' ');113 if (!env)114 break;115 *env = '\0';116 env++;117 }118 119 parse_options(envc, envv, check_options, env_usage, 0);120 }121 122 env = getenv("OBJTOOL_VERBOSE");123 if (env && !strcmp(env, "1"))124 opts.verbose = true;125 126 argc = parse_options(argc, argv, check_options, usage, 0);127 if (argc != 1)128 usage_with_options(usage, check_options);129 return argc;130}131 132static bool opts_valid(void)133{134 if (opts.hack_jump_label ||135 opts.hack_noinstr ||136 opts.ibt ||137 opts.mcount ||138 opts.noinstr ||139 opts.orc ||140 opts.retpoline ||141 opts.rethunk ||142 opts.sls ||143 opts.stackval ||144 opts.static_call ||145 opts.uaccess) {146 if (opts.dump_orc) {147 ERROR("--dump can't be combined with other actions");148 return false;149 }150 151 return true;152 }153 154 if (opts.unret && !opts.rethunk) {155 ERROR("--unret requires --rethunk");156 return false;157 }158 159 if (opts.dump_orc)160 return true;161 162 ERROR("At least one action required");163 return false;164}165 166static bool mnop_opts_valid(void)167{168 if (opts.mnop && !opts.mcount) {169 ERROR("--mnop requires --mcount");170 return false;171 }172 173 return true;174}175 176static bool link_opts_valid(struct objtool_file *file)177{178 if (opts.link)179 return true;180 181 if (has_multiple_files(file->elf)) {182 ERROR("Linked object detected, forcing --link");183 opts.link = true;184 return true;185 }186 187 if (opts.noinstr) {188 ERROR("--noinstr requires --link");189 return false;190 }191 192 if (opts.ibt) {193 ERROR("--ibt requires --link");194 return false;195 }196 197 if (opts.unret) {198 ERROR("--unret requires --link");199 return false;200 }201 202 return true;203}204 205int objtool_run(int argc, const char **argv)206{207 const char *objname;208 struct objtool_file *file;209 int ret;210 211 argc = cmd_parse_options(argc, argv, check_usage);212 objname = argv[0];213 214 if (!opts_valid())215 return 1;216 217 if (opts.dump_orc)218 return orc_dump(objname);219 220 file = objtool_open_read(objname);221 if (!file)222 return 1;223 224 if (!mnop_opts_valid())225 return 1;226 227 if (!link_opts_valid(file))228 return 1;229 230 ret = check(file);231 if (ret)232 return ret;233 234 if (file->elf->changed)235 return elf_write(file->elf);236 237 return 0;238}239