// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2015-2017 Josh Poimboeuf <jpoimboe@redhat.com> */ #include <subcmd/parse-options.h> #include <string.h> #include <stdlib.h> #include <objtool/builtin.h> #include <objtool/objtool.h> #define ERROR(format, ...) \ fprintf(stderr, \ "error: objtool: " format "\n", \ ##__VA_ARGS__) struct opts opts; static const char * const check_usage[] = { "objtool <actions> [<options>] file.o", NULL, }; static const char * const env_usage[] = { "OBJTOOL_ARGS=\"<options>\"", NULL, }; static int parse_dump(const struct option *opt, const char *str, int unset) { if (!str || !strcmp(str, "orc")) { opts.dump_orc = true; return 0; } return -1; } static int parse_hacks(const struct option *opt, const char *str, int unset) { bool found = false; /* * Use strstr() as a lazy method of checking for comma-separated * options. * * No string provided == enable all options. */ if (!str || strstr(str, "jump_label")) { opts.hack_jump_label = true; found = true; } if (!str || strstr(str, "noinstr")) { opts.hack_noinstr = true; found = true; } if (!str || strstr(str, "skylake")) { opts.hack_skylake = true; found = true; } return found ? 0 : -1; } const struct option check_options[] = { OPT_GROUP("Actions:"), OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label,noinstr,skylake", "patch toolchain bugs/limitations", parse_hacks), OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"), OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"), OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"), OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"), OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"), OPT_BOOLEAN(0, "rethunk", &opts.rethunk, "validate and annotate rethunk usage"), OPT_BOOLEAN(0, "unret", &opts.unret, "validate entry unret placement"), OPT_INTEGER(0, "prefix", &opts.prefix, "generate prefix symbols"), OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"), OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"), OPT_BOOLEAN('t', "static-call", &opts.static_call, "annotate static calls"), OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"), OPT_BOOLEAN(0 , "cfi", &opts.cfi, "annotate kernel control flow integrity (kCFI) function preambles"), OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump), OPT_GROUP("Options:"), OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"), OPT_BOOLEAN(0, "backup", &opts.backup, "create .orig files before modification"), OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"), OPT_BOOLEAN(0, "link", &opts.link, "object is a linked object"), OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"), OPT_BOOLEAN(0, "mnop", &opts.mnop, "nop out mcount call sites"), OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"), OPT_BOOLEAN(0, "sec-address", &opts.sec_address, "print section addresses in warnings"), OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"), OPT_END(), }; int cmd_parse_options(int argc, const char **argv, const char * const usage[]) { const char *envv[16] = { }; char *env; int envc; env = getenv("OBJTOOL_ARGS"); if (env) { envv[0] = "OBJTOOL_ARGS"; for (envc = 1; envc < ARRAY_SIZE(envv); ) { envv[envc++] = env; env = strchr(env, ' '); if (!env) break; *env = '\0'; env++; } parse_options(envc, envv, check_options, env_usage, 0); } argc = parse_options(argc, argv, check_options, usage, 0); if (argc != 1) usage_with_options(usage, check_options); return argc; } static bool opts_valid(void) { if (opts.hack_jump_label || opts.hack_noinstr || opts.ibt || opts.mcount || opts.noinstr || opts.orc || opts.retpoline || opts.rethunk || opts.sls || opts.stackval || opts.static_call || opts.uaccess) { if (opts.dump_orc) { ERROR("--dump can't be combined with other options"); return false; } return true; } if (opts.unret && !opts.rethunk) { ERROR("--unret requires --rethunk"); return false; } if (opts.dump_orc) return true; ERROR("At least one command required"); return false; } static bool mnop_opts_valid(void) { if (opts.mnop && !opts.mcount) { ERROR("--mnop requires --mcount"); return false; } return true; } static bool link_opts_valid(struct objtool_file *file) { if (opts.link) return true; if (has_multiple_files(file->elf)) { ERROR("Linked object detected, forcing --link"); opts.link = true; return true; } if (opts.noinstr) { ERROR("--noinstr requires --link"); return false; } if (opts.ibt) { ERROR("--ibt requires --link"); return false; } if (opts.unret) { ERROR("--unret requires --link"); return false; } return true; } int objtool_run(int argc, const char **argv) { const char *objname; struct objtool_file *file; int ret; argc = cmd_parse_options(argc, argv, check_usage); objname = argv[0]; if (!opts_valid()) return 1; if (opts.dump_orc) return orc_dump(objname); file = objtool_open_read(objname); if (!file) return 1; if (!mnop_opts_valid()) return 1; if (!link_opts_valid(file)) return 1; ret = check(file); if (ret) return ret; if (file->elf->changed) return elf_write(file->elf); return 0; }