1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 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 17 struct opts opts; 18 19 static const char * const check_usage[] = { 20 "objtool <actions> [<options>] file.o", 21 NULL, 22 }; 23 24 static const char * const env_usage[] = { 25 "OBJTOOL_ARGS=\"<options>\"", 26 NULL, 27 }; 28 29 static 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 39 static 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-separated 45 * 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 return found ? 0 : -1; 61 } 62 63 const struct option check_options[] = { 64 OPT_GROUP("Actions:"), 65 OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr", "patch toolchain bugs/limitations", parse_hacks), 66 OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"), 67 OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"), 68 OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"), 69 OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"), 70 OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"), 71 OPT_BOOLEAN(0, "rethunk", &opts.rethunk, "validate and annotate rethunk usage"), 72 OPT_BOOLEAN(0, "unret", &opts.unret, "validate entry unret placement"), 73 OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"), 74 OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"), 75 OPT_BOOLEAN('t', "static-call", &opts.static_call, "annotate static calls"), 76 OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"), 77 OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump), 78 79 OPT_GROUP("Options:"), 80 OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"), 81 OPT_BOOLEAN(0, "backup", &opts.backup, "create .orig files before modification"), 82 OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"), 83 OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"), 84 OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"), 85 OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"), 86 OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"), 87 OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"), 88 89 OPT_END(), 90 }; 91 92 int cmd_parse_options(int argc, const char **argv, const char * const usage[]) 93 { 94 const char *envv[16] = { }; 95 char *env; 96 int envc; 97 98 env = getenv("OBJTOOL_ARGS"); 99 if (env) { 100 envv[0] = "OBJTOOL_ARGS"; 101 for (envc = 1; envc < ARRAY_SIZE(envv); ) { 102 envv[envc++] = env; 103 env = strchr(env, ' '); 104 if (!env) 105 break; 106 *env = '\0'; 107 env++; 108 } 109 110 parse_options(envc, envv, check_options, env_usage, 0); 111 } 112 113 argc = parse_options(argc, argv, check_options, usage, 0); 114 if (argc != 1) 115 usage_with_options(usage, check_options); 116 return argc; 117 } 118 119 static bool opts_valid(void) 120 { 121 if (opts.hack_jump_label || 122 opts.hack_noinstr || 123 opts.ibt || 124 opts.mcount || 125 opts.noinstr || 126 opts.orc || 127 opts.retpoline || 128 opts.rethunk || 129 opts.sls || 130 opts.stackval || 131 opts.static_call || 132 opts.uaccess) { 133 if (opts.dump_orc) { 134 ERROR("--dump can't be combined with other options"); 135 return false; 136 } 137 138 return true; 139 } 140 141 if (opts.unret && !opts.rethunk) { 142 ERROR("--unret requires --rethunk"); 143 return false; 144 } 145 146 if (opts.dump_orc) 147 return true; 148 149 ERROR("At least one command required"); 150 return false; 151 } 152 153 static bool link_opts_valid(struct objtool_file *file) 154 { 155 if (opts.link) 156 return true; 157 158 if (has_multiple_files(file->elf)) { 159 ERROR("Linked object detected, forcing --link"); 160 opts.link = true; 161 return true; 162 } 163 164 if (opts.noinstr) { 165 ERROR("--noinstr requires --link"); 166 return false; 167 } 168 169 if (opts.ibt) { 170 ERROR("--ibt requires --link"); 171 return false; 172 } 173 174 if (opts.unret) { 175 ERROR("--unret requires --link"); 176 return false; 177 } 178 179 return true; 180 } 181 182 int objtool_run(int argc, const char **argv) 183 { 184 const char *objname; 185 struct objtool_file *file; 186 int ret; 187 188 argc = cmd_parse_options(argc, argv, check_usage); 189 objname = argv[0]; 190 191 if (!opts_valid()) 192 return 1; 193 194 if (opts.dump_orc) 195 return orc_dump(objname); 196 197 file = objtool_open_read(objname); 198 if (!file) 199 return 1; 200 201 if (!link_opts_valid(file)) 202 return 1; 203 204 ret = check(file); 205 if (ret) 206 return ret; 207 208 if (file->elf->changed) 209 return elf_write(file->elf); 210 211 return 0; 212 } 213