LXR linux/tools/objtool/builtin-check.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright (C) 2015-2017 Josh Poimboeuf <jpoimboe@redhat.com>
   4 */
   5
   6/*
   7 * objtool check:
   8 *
   9 * This command analyzes every .o file and ensures the validity of its stack
  10 * trace metadata.  It enforces a set of rules on asm code and C inline
  11 * assembly code so that stack traces can be reliable.
  12 *
  13 * For more information, see tools/objtool/Documentation/stack-validation.txt.
  14 */
  15
  16#include <subcmd/parse-options.h>
  17#include <string.h>
  18#include <stdlib.h>
  19#include <objtool/builtin.h>
  20#include <objtool/objtool.h>
  21
  22bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats,
  23     validate_dup, vmlinux, mcount, noinstr, backup;
  24
  25static const char * const check_usage[] = {
  26        "objtool check [<options>] file.o",
  27        NULL,
  28};
  29
  30static const char * const env_usage[] = {
  31        "OBJTOOL_ARGS=\"<options>\"",
  32        NULL,
  33};
  34
  35const struct option check_options[] = {
  36        OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"),
  37        OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"),
  38        OPT_BOOLEAN('r', "retpoline", &retpoline, "Validate retpoline assumptions"),
  39        OPT_BOOLEAN('m', "module", &module, "Indicates the object will be part of a kernel module"),
  40        OPT_BOOLEAN('b', "backtrace", &backtrace, "unwind on error"),
  41        OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"),
  42        OPT_BOOLEAN('s', "stats", &stats, "print statistics"),
  43        OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"),
  44        OPT_BOOLEAN('n', "noinstr", &noinstr, "noinstr validation for vmlinux.o"),
  45        OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"),
  46        OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"),
  47        OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"),
  48        OPT_END(),
  49};
  50
  51int cmd_parse_options(int argc, const char **argv, const char * const usage[])
  52{
  53        const char *envv[16] = { };
  54        char *env;
  55        int envc;
  56
  57        env = getenv("OBJTOOL_ARGS");
  58        if (env) {
  59                envv[0] = "OBJTOOL_ARGS";
  60                for (envc = 1; envc < ARRAY_SIZE(envv); ) {
  61                        envv[envc++] = env;
  62                        env = strchr(env, ' ');
  63                        if (!env)
  64                                break;
  65                        *env = '\0';
  66                        env++;
  67                }
  68
  69                parse_options(envc, envv, check_options, env_usage, 0);
  70        }
  71
  72        argc = parse_options(argc, argv, check_options, usage, 0);
  73        if (argc != 1)
  74                usage_with_options(usage, check_options);
  75        return argc;
  76}
  77
  78int cmd_check(int argc, const char **argv)
  79{
  80        const char *objname;
  81        struct objtool_file *file;
  82        int ret;
  83
  84        argc = cmd_parse_options(argc, argv, check_usage);
  85        objname = argv[0];
  86
  87        file = objtool_open_read(objname);
  88        if (!file)
  89                return 1;
  90
  91        ret = check(file);
  92        if (ret)
  93                return ret;
  94
  95        if (file->elf->changed)
  96                return elf_write(file->elf);
  97
  98        return 0;
  99}
 100