1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> |
4 | */ |
5 | |
6 | #include <stdio.h> |
7 | #include <stdbool.h> |
8 | #include <string.h> |
9 | #include <stdlib.h> |
10 | #include <unistd.h> |
11 | #include <subcmd/exec-cmd.h> |
12 | #include <subcmd/pager.h> |
13 | #include <linux/kernel.h> |
14 | |
15 | #include <objtool/builtin.h> |
16 | #include <objtool/objtool.h> |
17 | #include <objtool/warn.h> |
18 | |
19 | bool help; |
20 | |
21 | const char *objname; |
22 | static struct objtool_file file; |
23 | |
24 | static bool objtool_create_backup(const char *_objname) |
25 | { |
26 | int len = strlen(_objname); |
27 | char *buf, *base, *name = malloc(len+6); |
28 | int s, d, l, t; |
29 | |
30 | if (!name) { |
31 | perror("failed backup name malloc" ); |
32 | return false; |
33 | } |
34 | |
35 | strcpy(name, _objname); |
36 | strcpy(name + len, ".orig" ); |
37 | |
38 | d = open(name, O_CREAT|O_WRONLY|O_TRUNC, 0644); |
39 | if (d < 0) { |
40 | perror("failed to create backup file" ); |
41 | return false; |
42 | } |
43 | |
44 | s = open(_objname, O_RDONLY); |
45 | if (s < 0) { |
46 | perror("failed to open orig file" ); |
47 | return false; |
48 | } |
49 | |
50 | buf = malloc(4096); |
51 | if (!buf) { |
52 | perror("failed backup data malloc" ); |
53 | return false; |
54 | } |
55 | |
56 | while ((l = read(s, buf, 4096)) > 0) { |
57 | base = buf; |
58 | do { |
59 | t = write(d, base, l); |
60 | if (t < 0) { |
61 | perror("failed backup write" ); |
62 | return false; |
63 | } |
64 | base += t; |
65 | l -= t; |
66 | } while (l); |
67 | } |
68 | |
69 | if (l < 0) { |
70 | perror("failed backup read" ); |
71 | return false; |
72 | } |
73 | |
74 | free(name); |
75 | free(buf); |
76 | close(d); |
77 | close(s); |
78 | |
79 | return true; |
80 | } |
81 | |
82 | struct objtool_file *objtool_open_read(const char *_objname) |
83 | { |
84 | if (objname) { |
85 | if (strcmp(objname, _objname)) { |
86 | WARN("won't handle more than one file at a time" ); |
87 | return NULL; |
88 | } |
89 | return &file; |
90 | } |
91 | objname = _objname; |
92 | |
93 | file.elf = elf_open_read(objname, O_RDWR); |
94 | if (!file.elf) |
95 | return NULL; |
96 | |
97 | if (opts.backup && !objtool_create_backup(objname: objname)) { |
98 | WARN("can't create backup file" ); |
99 | return NULL; |
100 | } |
101 | |
102 | hash_init(file.insn_hash); |
103 | INIT_LIST_HEAD(&file.retpoline_call_list); |
104 | INIT_LIST_HEAD(&file.return_thunk_list); |
105 | INIT_LIST_HEAD(&file.static_call_list); |
106 | INIT_LIST_HEAD(&file.mcount_loc_list); |
107 | INIT_LIST_HEAD(&file.endbr_list); |
108 | INIT_LIST_HEAD(&file.call_list); |
109 | file.ignore_unreachables = opts.no_unreachable; |
110 | file.hints = false; |
111 | |
112 | return &file; |
113 | } |
114 | |
115 | void objtool_pv_add(struct objtool_file *f, int idx, struct symbol *func) |
116 | { |
117 | if (!opts.noinstr) |
118 | return; |
119 | |
120 | if (!f->pv_ops) { |
121 | WARN("paravirt confusion" ); |
122 | return; |
123 | } |
124 | |
125 | /* |
126 | * These functions will be patched into native code, |
127 | * see paravirt_patch(). |
128 | */ |
129 | if (!strcmp(func->name, "_paravirt_nop" ) || |
130 | !strcmp(func->name, "_paravirt_ident_64" )) |
131 | return; |
132 | |
133 | /* already added this function */ |
134 | if (!list_empty(&func->pv_target)) |
135 | return; |
136 | |
137 | list_add(&func->pv_target, &f->pv_ops[idx].targets); |
138 | f->pv_ops[idx].clean = false; |
139 | } |
140 | |
141 | int main(int argc, const char **argv) |
142 | { |
143 | static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED" ; |
144 | |
145 | /* libsubcmd init */ |
146 | exec_cmd_init("objtool" , UNUSED, UNUSED, UNUSED); |
147 | pager_init(UNUSED); |
148 | |
149 | return objtool_run(argc, argv); |
150 | } |
151 | |