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('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"), 72 OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"), 73 OPT_BOOLEAN('t', "static-call", &opts.static_call, "annotate static calls"), 74 OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"), 75 OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump), 76 77 OPT_GROUP("Options:"), 78 OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"), 79 OPT_BOOLEAN(0, "backup", &opts.backup, "create .orig files before modification"), 80 OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"), 81 OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"), 82 OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"), 83 OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"), 84 OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"), 85 OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"), 86 87 OPT_END(), 88 }; 89 90 int cmd_parse_options(int argc, const char **argv, const char * const usage[]) 91 { 92 const char *envv[16] = { }; 93 char *env; 94 int envc; 95 96 env = getenv("OBJTOOL_ARGS"); 97 if (env) { 98 envv[0] = "OBJTOOL_ARGS"; 99 for (envc = 1; envc < ARRAY_SIZE(envv); ) { 100 envv[envc++] = env; 101 env = strchr(env, ' '); 102 if (!env) 103 break; 104 *env = '\0'; 105 env++; 106 } 107 108 parse_options(envc, envv, check_options, env_usage, 0); 109 } 110 111 argc = parse_options(argc, argv, check_options, usage, 0); 112 if (argc != 1) 113 usage_with_options(usage, check_options); 114 return argc; 115 } 116 117 static bool opts_valid(void) 118 { 119 if (opts.hack_jump_label || 120 opts.hack_noinstr || 121 opts.ibt || 122 opts.mcount || 123 opts.noinstr || 124 opts.orc || 125 opts.retpoline || 126 opts.sls || 127 opts.stackval || 128 opts.static_call || 129 opts.uaccess) { 130 if (opts.dump_orc) { 131 ERROR("--dump can't be combined with other options"); 132 return false; 133 } 134 135 return true; 136 } 137 138 if (opts.dump_orc) 139 return true; 140 141 ERROR("At least one command required"); 142 return false; 143 } 144 145 static bool link_opts_valid(struct objtool_file *file) 146 { 147 if (opts.link) 148 return true; 149 150 if (has_multiple_files(file->elf)) { 151 ERROR("Linked object detected, forcing --link"); 152 opts.link = true; 153 return true; 154 } 155 156 if (opts.noinstr) { 157 ERROR("--noinstr requires --link"); 158 return false; 159 } 160 161 if (opts.ibt) { 162 ERROR("--ibt requires --link"); 163 return false; 164 } 165 166 return true; 167 } 168 169 int objtool_run(int argc, const char **argv) 170 { 171 const char *objname; 172 struct objtool_file *file; 173 int ret; 174 175 argc = cmd_parse_options(argc, argv, check_usage); 176 objname = argv[0]; 177 178 if (!opts_valid()) 179 return 1; 180 181 if (opts.dump_orc) 182 return orc_dump(objname); 183 184 file = objtool_open_read(objname); 185 if (!file) 186 return 1; 187 188 if (!link_opts_valid(file)) 189 return 1; 190 191 ret = check(file); 192 if (ret) 193 return ret; 194 195 if (file->elf->changed) 196 return elf_write(file->elf); 197 198 return 0; 199 } 200