1*06c3fb27SDimitry Andric //===-- msan_dl.cpp -------------------------------------------------------===//
2*06c3fb27SDimitry Andric //
3*06c3fb27SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*06c3fb27SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*06c3fb27SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*06c3fb27SDimitry Andric //
7*06c3fb27SDimitry Andric //===----------------------------------------------------------------------===//
8*06c3fb27SDimitry Andric //
9*06c3fb27SDimitry Andric // This file is a part of MemorySanitizer.
10*06c3fb27SDimitry Andric //
11*06c3fb27SDimitry Andric // Helper functions for unpoisoning results of dladdr and dladdr1.
12*06c3fb27SDimitry Andric //===----------------------------------------------------------------------===//
13*06c3fb27SDimitry Andric
14*06c3fb27SDimitry Andric #include "msan_dl.h"
15*06c3fb27SDimitry Andric
16*06c3fb27SDimitry Andric #include <dlfcn.h>
17*06c3fb27SDimitry Andric #include <elf.h>
18*06c3fb27SDimitry Andric #include <link.h>
19*06c3fb27SDimitry Andric
20*06c3fb27SDimitry Andric #include "msan_poisoning.h"
21*06c3fb27SDimitry Andric
22*06c3fb27SDimitry Andric namespace __msan {
23*06c3fb27SDimitry Andric
UnpoisonDllAddrInfo(void * info)24*06c3fb27SDimitry Andric void UnpoisonDllAddrInfo(void *info) {
25*06c3fb27SDimitry Andric Dl_info *ptr = (Dl_info *)(info);
26*06c3fb27SDimitry Andric __msan_unpoison(ptr, sizeof(*ptr));
27*06c3fb27SDimitry Andric if (ptr->dli_fname)
28*06c3fb27SDimitry Andric __msan_unpoison(ptr->dli_fname, internal_strlen(ptr->dli_fname) + 1);
29*06c3fb27SDimitry Andric if (ptr->dli_sname)
30*06c3fb27SDimitry Andric __msan_unpoison(ptr->dli_sname, internal_strlen(ptr->dli_sname) + 1);
31*06c3fb27SDimitry Andric }
32*06c3fb27SDimitry Andric
33*06c3fb27SDimitry Andric #if SANITIZER_GLIBC
UnpoisonDllAddr1ExtraInfo(void ** extra_info,int flags)34*06c3fb27SDimitry Andric void UnpoisonDllAddr1ExtraInfo(void **extra_info, int flags) {
35*06c3fb27SDimitry Andric if (flags == RTLD_DL_SYMENT) {
36*06c3fb27SDimitry Andric __msan_unpoison(extra_info, sizeof(void *));
37*06c3fb27SDimitry Andric
38*06c3fb27SDimitry Andric ElfW(Sym) *s = *((ElfW(Sym) **)(extra_info));
39*06c3fb27SDimitry Andric __msan_unpoison(s, sizeof(ElfW(Sym)));
40*06c3fb27SDimitry Andric } else if (flags == RTLD_DL_LINKMAP) {
41*06c3fb27SDimitry Andric __msan_unpoison(extra_info, sizeof(void *));
42*06c3fb27SDimitry Andric
43*06c3fb27SDimitry Andric struct link_map *map = *((struct link_map **)(extra_info));
44*06c3fb27SDimitry Andric
45*06c3fb27SDimitry Andric // Walk forward
46*06c3fb27SDimitry Andric for (auto *ptr = map; ptr; ptr = ptr->l_next) {
47*06c3fb27SDimitry Andric __msan_unpoison(ptr, sizeof(struct link_map));
48*06c3fb27SDimitry Andric if (ptr->l_name)
49*06c3fb27SDimitry Andric __msan_unpoison(ptr->l_name, internal_strlen(ptr->l_name) + 1);
50*06c3fb27SDimitry Andric }
51*06c3fb27SDimitry Andric
52*06c3fb27SDimitry Andric if (!map)
53*06c3fb27SDimitry Andric return;
54*06c3fb27SDimitry Andric
55*06c3fb27SDimitry Andric // Walk backward
56*06c3fb27SDimitry Andric for (auto *ptr = map->l_prev; ptr; ptr = ptr->l_prev) {
57*06c3fb27SDimitry Andric __msan_unpoison(ptr, sizeof(struct link_map));
58*06c3fb27SDimitry Andric if (ptr->l_name)
59*06c3fb27SDimitry Andric __msan_unpoison(ptr->l_name, internal_strlen(ptr->l_name) + 1);
60*06c3fb27SDimitry Andric }
61*06c3fb27SDimitry Andric }
62*06c3fb27SDimitry Andric }
63*06c3fb27SDimitry Andric #endif
64*06c3fb27SDimitry Andric
65*06c3fb27SDimitry Andric } // namespace __msan
66