1 | /* Read the dynamic section at DYN and fill in INFO with indices DT_*. |
2 | Copyright (C) 2012-2016 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <http://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <assert.h> |
20 | #include <libc-internal.h> |
21 | |
22 | #ifndef RESOLVE_MAP |
23 | static |
24 | #else |
25 | auto |
26 | #endif |
27 | inline void __attribute__ ((unused, always_inline)) |
28 | elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp) |
29 | { |
30 | ElfW(Dyn) *dyn = l->l_ld; |
31 | ElfW(Dyn) **info; |
32 | #if __ELF_NATIVE_CLASS == 32 |
33 | typedef Elf32_Word d_tag_utype; |
34 | #elif __ELF_NATIVE_CLASS == 64 |
35 | typedef Elf64_Xword d_tag_utype; |
36 | #endif |
37 | |
38 | #ifndef RTLD_BOOTSTRAP |
39 | if (dyn == NULL) |
40 | return; |
41 | #endif |
42 | |
43 | info = l->l_info; |
44 | |
45 | while (dyn->d_tag != DT_NULL) |
46 | { |
47 | if ((d_tag_utype) dyn->d_tag < DT_NUM) |
48 | info[dyn->d_tag] = dyn; |
49 | else if (dyn->d_tag >= DT_LOPROC && |
50 | dyn->d_tag < DT_LOPROC + DT_THISPROCNUM) |
51 | { |
52 | /* This does not violate the array bounds of l->l_info, but |
53 | gcc 4.6 on sparc somehow does not see this. */ |
54 | DIAG_PUSH_NEEDS_COMMENT; |
55 | DIAG_IGNORE_NEEDS_COMMENT (4.6, |
56 | "-Warray-bounds" ); |
57 | info[dyn->d_tag - DT_LOPROC + DT_NUM] = dyn; |
58 | DIAG_POP_NEEDS_COMMENT; |
59 | } |
60 | else if ((d_tag_utype) DT_VERSIONTAGIDX (dyn->d_tag) < DT_VERSIONTAGNUM) |
61 | info[VERSYMIDX (dyn->d_tag)] = dyn; |
62 | else if ((d_tag_utype) DT_EXTRATAGIDX (dyn->d_tag) < DT_EXTRANUM) |
63 | info[DT_EXTRATAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM |
64 | + DT_VERSIONTAGNUM] = dyn; |
65 | else if ((d_tag_utype) DT_VALTAGIDX (dyn->d_tag) < DT_VALNUM) |
66 | info[DT_VALTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM |
67 | + DT_VERSIONTAGNUM + DT_EXTRANUM] = dyn; |
68 | else if ((d_tag_utype) DT_ADDRTAGIDX (dyn->d_tag) < DT_ADDRNUM) |
69 | info[DT_ADDRTAGIDX (dyn->d_tag) + DT_NUM + DT_THISPROCNUM |
70 | + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] = dyn; |
71 | ++dyn; |
72 | } |
73 | |
74 | #define DL_RO_DYN_TEMP_CNT 8 |
75 | |
76 | #ifndef DL_RO_DYN_SECTION |
77 | /* Don't adjust .dynamic unnecessarily. */ |
78 | if (l->l_addr != 0) |
79 | { |
80 | ElfW(Addr) l_addr = l->l_addr; |
81 | int cnt = 0; |
82 | |
83 | # define ADJUST_DYN_INFO(tag) \ |
84 | do \ |
85 | if (info[tag] != NULL) \ |
86 | { \ |
87 | if (temp) \ |
88 | { \ |
89 | temp[cnt].d_tag = info[tag]->d_tag; \ |
90 | temp[cnt].d_un.d_ptr = info[tag]->d_un.d_ptr + l_addr; \ |
91 | info[tag] = temp + cnt++; \ |
92 | } \ |
93 | else \ |
94 | info[tag]->d_un.d_ptr += l_addr; \ |
95 | } \ |
96 | while (0) |
97 | |
98 | ADJUST_DYN_INFO (DT_HASH); |
99 | ADJUST_DYN_INFO (DT_PLTGOT); |
100 | ADJUST_DYN_INFO (DT_STRTAB); |
101 | ADJUST_DYN_INFO (DT_SYMTAB); |
102 | # if ! ELF_MACHINE_NO_RELA |
103 | ADJUST_DYN_INFO (DT_RELA); |
104 | # endif |
105 | # if ! ELF_MACHINE_NO_REL |
106 | ADJUST_DYN_INFO (DT_REL); |
107 | # endif |
108 | ADJUST_DYN_INFO (DT_JMPREL); |
109 | ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM)); |
110 | ADJUST_DYN_INFO (DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM |
111 | + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM); |
112 | # undef ADJUST_DYN_INFO |
113 | assert (cnt <= DL_RO_DYN_TEMP_CNT); |
114 | } |
115 | #endif |
116 | if (info[DT_PLTREL] != NULL) |
117 | { |
118 | #if ELF_MACHINE_NO_RELA |
119 | assert (info[DT_PLTREL]->d_un.d_val == DT_REL); |
120 | #elif ELF_MACHINE_NO_REL |
121 | assert (info[DT_PLTREL]->d_un.d_val == DT_RELA); |
122 | #else |
123 | assert (info[DT_PLTREL]->d_un.d_val == DT_REL |
124 | || info[DT_PLTREL]->d_un.d_val == DT_RELA); |
125 | #endif |
126 | } |
127 | #if ! ELF_MACHINE_NO_RELA |
128 | if (info[DT_RELA] != NULL) |
129 | assert (info[DT_RELAENT]->d_un.d_val == sizeof (ElfW(Rela))); |
130 | # endif |
131 | # if ! ELF_MACHINE_NO_REL |
132 | if (info[DT_REL] != NULL) |
133 | assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel))); |
134 | #endif |
135 | #ifdef RTLD_BOOTSTRAP |
136 | /* Only the bind now flags are allowed. */ |
137 | assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL |
138 | || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0); |
139 | assert (info[DT_FLAGS] == NULL |
140 | || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0); |
141 | /* Flags must not be set for ld.so. */ |
142 | assert (info[DT_RUNPATH] == NULL); |
143 | assert (info[DT_RPATH] == NULL); |
144 | #else |
145 | if (info[DT_FLAGS] != NULL) |
146 | { |
147 | /* Flags are used. Translate to the old form where available. |
148 | Since these l_info entries are only tested for NULL pointers it |
149 | is ok if they point to the DT_FLAGS entry. */ |
150 | l->l_flags = info[DT_FLAGS]->d_un.d_val; |
151 | |
152 | if (l->l_flags & DF_SYMBOLIC) |
153 | info[DT_SYMBOLIC] = info[DT_FLAGS]; |
154 | if (l->l_flags & DF_TEXTREL) |
155 | info[DT_TEXTREL] = info[DT_FLAGS]; |
156 | if (l->l_flags & DF_BIND_NOW) |
157 | info[DT_BIND_NOW] = info[DT_FLAGS]; |
158 | } |
159 | if (info[VERSYMIDX (DT_FLAGS_1)] != NULL) |
160 | { |
161 | l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val; |
162 | |
163 | /* Only DT_1_SUPPORTED_MASK bits are supported, and we would like |
164 | to assert this, but we can't. Users have been setting |
165 | unsupported DF_1_* flags for a long time and glibc has ignored |
166 | them. Therefore to avoid breaking existing applications the |
167 | best we can do is add a warning during debugging with the |
168 | intent of notifying the user of the problem. */ |
169 | if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0) |
170 | && l->l_flags_1 & ~DT_1_SUPPORTED_MASK) |
171 | _dl_debug_printf ("\nWARNING: Unsupported flag value(s) of 0x%x in DT_FLAGS_1.\n" , |
172 | l->l_flags_1 & ~DT_1_SUPPORTED_MASK); |
173 | |
174 | if (l->l_flags_1 & DF_1_NOW) |
175 | info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)]; |
176 | } |
177 | if (info[DT_RUNPATH] != NULL) |
178 | /* If both RUNPATH and RPATH are given, the latter is ignored. */ |
179 | info[DT_RPATH] = NULL; |
180 | #endif |
181 | } |
182 | |