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 <objtool/builtin.h> 19 #include <objtool/objtool.h> 20 21 bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, 22 validate_dup, vmlinux, mcount, noinstr, backup; 23 24 static const char * const check_usage[] = { 25 "objtool check [<options>] file.o", 26 NULL, 27 }; 28 29 const struct option check_options[] = { 30 OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"), 31 OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"), 32 OPT_BOOLEAN('r', "retpoline", &retpoline, "Validate retpoline assumptions"), 33 OPT_BOOLEAN('m', "module", &module, "Indicates the object will be part of a kernel module"), 34 OPT_BOOLEAN('b', "backtrace", &backtrace, "unwind on error"), 35 OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"), 36 OPT_BOOLEAN('s', "stats", &stats, "print statistics"), 37 OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"), 38 OPT_BOOLEAN('n', "noinstr", &noinstr, "noinstr validation for vmlinux.o"), 39 OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"), 40 OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), 41 OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"), 42 OPT_END(), 43 }; 44 45 int cmd_parse_options(int argc, const char **argv, const char * const usage[]) 46 { 47 argc = parse_options(argc, argv, check_options, usage, 0); 48 if (argc != 1) 49 usage_with_options(usage, check_options); 50 return argc; 51 } 52 53 int cmd_check(int argc, const char **argv) 54 { 55 const char *objname; 56 struct objtool_file *file; 57 int ret; 58 59 argc = cmd_parse_options(argc, argv, check_usage); 60 objname = argv[0]; 61 62 file = objtool_open_read(objname); 63 if (!file) 64 return 1; 65 66 ret = check(file); 67 if (ret) 68 return ret; 69 70 if (file->elf->changed) 71 return elf_write(file->elf); 72 73 return 0; 74 } 75