// 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 <fcntl.h>#include <unistd.h>#include <errno.h>#include <sys/stat.h>#include <sys/sendfile.h>#include <objtool/builtin.h>#include <objtool/objtool.h>#include <objtool/warn.h> #define ORIG_SUFFIX ".orig" int orig_argc;static char **orig_argv;const char *objname;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;} static const struct option check_options[] = {	OPT_GROUP("Actions:"),	OPT_STRING_OPTARG('d',	 "disas", &opts.disas, "function-pattern", "disassemble functions", "*"),	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(0,		 "klp-symids", &opts.klp_symids, "generate .klp.symids for duplicate symbol disambiguation"),	OPT_BOOLEAN('m',	 "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"),	OPT_BOOLEAN(0,		 "noabs", &opts.noabs, "reject absolute references in allocatable sections"),	OPT_BOOLEAN('n',	 "noinstr", &opts.noinstr, "validate noinstr rules"),	OPT_BOOLEAN(0,		 "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 or grow prefix symbols for N-byte function padding"),	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_CALLBACK_OPTARG(0,	 "dump", NULL, NULL, "orc", "dump metadata", parse_dump), 	OPT_GROUP("Options:"),	OPT_BOOLEAN(0,		 "cfi", &opts.cfi, "grow kCFI preamble symbols (use with --prefix)"),	OPT_BOOLEAN(0,		 "fineibt", &opts.fineibt, "create .cfi_sites section for FineIBT"),	OPT_BOOLEAN(0,		 "backtrace", &opts.backtrace, "unwind on error"),	OPT_BOOLEAN(0,		 "backup", &opts.backup, "create backup (.orig) file on warning/error"),	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_STRING('o',		 "output", &opts.output, "file", "output file name"),	OPT_BOOLEAN(0,		 "sec-address", &opts.sec_address, "print section addresses in warnings"),	OPT_BOOLEAN(0,		 "stats", &opts.stats, "print statistics"),	OPT_STRING(0,		 "trace", &opts.trace, "func", "trace function validation"),	OPT_BOOLEAN('v',	 "verbose", &opts.verbose, "verbose warnings"),	OPT_BOOLEAN(0,		 "werror", &opts.werror, "return error on warnings"),	OPT_BOOLEAN(0,		 "wide", &opts.wide, "wide output"), 	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);	} 	env = getenv("OBJTOOL_VERBOSE");	if (env && !strcmp(env, "1"))		opts.verbose = true; 	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.mnop && !opts.mcount) {		ERROR("--mnop requires --mcount");		return false;	} 	if (opts.noinstr && !opts.link) {		ERROR("--noinstr requires --link");		return false;	} 	if (opts.ibt && !opts.link) {		ERROR("--ibt requires --link");		return false;	} 	if (opts.unret && !opts.link) {		ERROR("--unret requires --link");		return false;	} 	if (opts.cfi && !opts.prefix) {		ERROR("--cfi requires --prefix");		return false;	} 	if (opts.fineibt && !opts.cfi) {		ERROR("--fineibt requires --cfi");		return false;	} 	if (opts.klp_symids && !opts.link) {		ERROR("--klp-symids requires --link");		return false;	} 	if (opts.disas			||	    opts.hack_jump_label	||	    opts.hack_noinstr		||	    opts.ibt			||	    opts.klp_symids		||	    opts.mcount			||	    opts.noabs			||	    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 actions");			return false;		} 		return true;	} 	if (opts.dump_orc)		return true; 	ERROR("At least one action required");	return false;} static int copy_file(const char *src, const char *dst){	size_t to_copy, copied;	int dst_fd, src_fd;	struct stat stat;	off_t offset = 0; 	src_fd = open(src, O_RDONLY);	if (src_fd == -1) {		ERROR("can't open %s for reading: %s", src, strerror(errno));		return 1;	} 	dst_fd = open(dst, O_WRONLY | O_CREAT | O_TRUNC, 0400);	if (dst_fd == -1) {		ERROR("can't open %s for writing: %s", dst, strerror(errno));		return 1;	} 	if (fstat(src_fd, &stat) == -1) {		ERROR_GLIBC("fstat");		return 1;	} 	if (fchmod(dst_fd, stat.st_mode) == -1) {		ERROR_GLIBC("fchmod");		return 1;	} 	for (to_copy = stat.st_size; to_copy > 0; to_copy -= copied) {		copied = sendfile(dst_fd, src_fd, &offset, to_copy);		if (copied == -1) {			ERROR_GLIBC("sendfile");			return 1;		}	} 	close(dst_fd);	close(src_fd);	return 0;} static void save_argv(int argc, const char **argv){	orig_argv = calloc(argc, sizeof(char *));	if (!orig_argv) {		ERROR_GLIBC("calloc");		exit(1);	} 	for (int i = 0; i < argc; i++) {		orig_argv[i] = strdup(argv[i]);		if (!orig_argv[i]) {			ERROR_GLIBC("strdup(%s)", argv[i]);			exit(1);		}	}} int make_backup(void){	char *backup; 	/*	 * Make a backup before kbuild deletes the file so the error	 * can be recreated without recompiling or relinking.	 */	backup = malloc(strlen(objname) + strlen(ORIG_SUFFIX) + 1);	if (!backup) {		ERROR_GLIBC("malloc");		return 1;	} 	strcpy(backup, objname);	strcat(backup, ORIG_SUFFIX);	if (copy_file(objname, backup))		return 1; 	/*	 * Print the cmdline args to make it easier to recreate.	 */ 	fprintf(stderr, "%s", orig_argv[0]); 	for (int i = 1; i < orig_argc; i++) {		char *arg = orig_argv[i]; 		/* Modify the printed args to use the backup */		if (!opts.output && !strcmp(arg, objname))			fprintf(stderr, " %s -o %s", backup, objname);		else			fprintf(stderr, " %s", arg);	} 	fprintf(stderr, "\n");	return 0;} int objtool_run(int argc, const char **argv){	struct objtool_file *file;	int ret = 0; 	orig_argc = argc;	save_argv(argc, argv); 	cmd_parse_options(argc, argv, check_usage); 	if (!opts_valid())		return 1; 	objname = argv[0]; 	if (opts.dump_orc)		return orc_dump(objname); 	if (!opts.dryrun && opts.output) {		/* copy original .o file to output file */		if (copy_file(objname, opts.output))			return 1; 		/* from here on, work directly on the output file */		objname = opts.output;	} 	file = objtool_open_read(objname);	if (!file)		return 1; 	if (!opts.link && has_multiple_files(file->elf)) {		ERROR("Linked object requires --link");		return 1;	} 	ret = check(file);	if (ret)		return ret; 	if (!opts.dryrun && file->elf->changed && elf_write(file->elf))		return 1; 	return elf_close(file->elf);}