1 | /*- |
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2 | * Copyright (c) 2006-2011 Joseph Koshy |
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3 | * All rights reserved. |
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4 | * |
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5 | * Redistribution and use in source and binary forms, with or without |
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6 | * modification, are permitted provided that the following conditions |
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7 | * are met: |
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8 | * 1. Redistributions of source code must retain the above copyright |
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9 | * notice, this list of conditions and the following disclaimer. |
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10 | * 2. Redistributions in binary form must reproduce the above copyright |
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11 | * notice, this list of conditions and the following disclaimer in the |
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12 | * documentation and/or other materials provided with the distribution. |
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13 | * |
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14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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15 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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16 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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17 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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18 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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19 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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20 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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21 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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22 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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23 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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24 | * SUCH DAMAGE. |
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25 | */ |
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26 | |
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27 | #include <sys/mman.h> |
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28 | |
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29 | #include <assert.h> |
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30 | #include <errno.h> |
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31 | #include <gelf.h> |
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32 | #include <libelf.h> |
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33 | #include <stdlib.h> |
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34 | #include <string.h> |
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35 | #include <unistd.h> |
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36 | |
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37 | #include "_libelf.h" |
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38 | |
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39 | LIBELF_VCSID("$Id$"); |
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40 | |
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41 | /* |
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42 | * Layout strategy: |
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43 | * |
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44 | * - Case 1: ELF_F_LAYOUT is asserted |
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45 | * In this case the application has full control over where the |
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46 | * section header table, program header table, and section data |
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47 | * will reside. The library only perform error checks. |
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48 | * |
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49 | * - Case 2: ELF_F_LAYOUT is not asserted |
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50 | * |
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51 | * The library will do the object layout using the following |
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52 | * ordering: |
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53 | * - The executable header is placed first, are required by the |
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54 | * ELF specification. |
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55 | * - The program header table is placed immediately following the |
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56 | * executable header. |
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57 | * - Section data, if any, is placed after the program header |
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58 | * table, aligned appropriately. |
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59 | * - The section header table, if needed, is placed last. |
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60 | * |
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61 | * There are two sub-cases to be taken care of: |
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62 | * |
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63 | * - Case 2a: e->e_cmd == ELF_C_READ or ELF_C_RDWR |
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64 | * |
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65 | * In this sub-case, the underlying ELF object may already have |
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66 | * content in it, which the application may have modified. The |
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67 | * library will retrieve content from the existing object as |
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68 | * needed. |
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69 | * |
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70 | * - Case 2b: e->e_cmd == ELF_C_WRITE |
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71 | * |
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72 | * The ELF object is being created afresh in this sub-case; |
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73 | * there is no pre-existing content in the underlying ELF |
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74 | * object. |
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75 | */ |
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76 | |
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77 | /* |
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78 | * The types of extents in an ELF object. |
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79 | */ |
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80 | enum elf_extent { |
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81 | ELF_EXTENT_EHDR, |
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82 | ELF_EXTENT_PHDR, |
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83 | ELF_EXTENT_SECTION, |
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84 | ELF_EXTENT_SHDR |
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85 | }; |
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86 | |
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87 | /* |
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88 | * A extent descriptor, used when laying out an ELF object. |
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89 | */ |
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90 | struct _Elf_Extent { |
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91 | SLIST_ENTRY(_Elf_Extent) ex_next; |
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92 | uint64_t ex_start; /* Start of the region. */ |
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93 | uint64_t ex_size; /* The size of the region. */ |
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94 | enum elf_extent ex_type; /* Type of region. */ |
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95 | void *ex_desc; /* Associated descriptor. */ |
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96 | }; |
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97 | |
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98 | SLIST_HEAD(_Elf_Extent_List, _Elf_Extent); |
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99 | |
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100 | /* |
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101 | * Compute the extents of a section, by looking at the data |
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102 | * descriptors associated with it. The function returns 1 |
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103 | * if successful, or zero if an error was detected. |
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104 | */ |
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105 | static int |
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106 | _libelf_compute_section_extents(Elf *e, Elf_Scn *s, off_t rc) |
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107 | { |
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108 | int ec; |
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109 | size_t fsz, msz; |
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110 | Elf_Data *d; |
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111 | Elf32_Shdr *shdr32; |
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112 | Elf64_Shdr *shdr64; |
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113 | uint32_t sh_type; |
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114 | uint64_t d_align; |
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115 | unsigned int elftype; |
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116 | uint64_t scn_size, scn_alignment; |
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117 | uint64_t sh_align, sh_entsize, sh_offset, sh_size; |
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118 | |
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119 | ec = e->e_class; |
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120 | |
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121 | shdr32 = &s->s_shdr.s_shdr32; |
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122 | shdr64 = &s->s_shdr.s_shdr64; |
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123 | if (ec == ELFCLASS32) { |
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124 | sh_type = shdr32->sh_type; |
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125 | sh_align = (uint64_t) shdr32->sh_addralign; |
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126 | sh_entsize = (uint64_t) shdr32->sh_entsize; |
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127 | sh_offset = (uint64_t) shdr32->sh_offset; |
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128 | sh_size = (uint64_t) shdr32->sh_size; |
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129 | } else { |
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130 | sh_type = shdr64->sh_type; |
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131 | sh_align = shdr64->sh_addralign; |
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132 | sh_entsize = shdr64->sh_entsize; |
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133 | sh_offset = shdr64->sh_offset; |
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134 | sh_size = shdr64->sh_size; |
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135 | } |
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136 | |
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137 | assert(sh_type != SHT_NULL && sh_type != SHT_NOBITS); |
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138 | |
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139 | elftype = _libelf_xlate_shtype(sh_type); |
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140 | if (elftype > ELF_T_LAST) { |
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141 | LIBELF_SET_ERROR(SECTION, 0); |
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142 | return (0); |
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143 | } |
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144 | |
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145 | if (sh_align == 0) |
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146 | sh_align = _libelf_falign(elftype, ec); |
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147 | |
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148 | /* |
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149 | * Compute the section's size and alignment using the data |
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150 | * descriptors associated with the section. |
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151 | */ |
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152 | if (STAILQ_EMPTY(&s->s_data)) { |
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153 | /* |
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154 | * The section's content (if any) has not been read in |
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155 | * yet. If section is not dirty marked dirty, we can |
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156 | * reuse the values in the 'sh_size' and 'sh_offset' |
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157 | * fields of the section header. |
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158 | */ |
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159 | if ((s->s_flags & ELF_F_DIRTY) == 0) { |
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160 | /* |
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161 | * If the library is doing the layout, then we |
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162 | * compute the new start offset for the |
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163 | * section based on the current offset and the |
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164 | * section's alignment needs. |
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165 | * |
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166 | * If the application is doing the layout, we |
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167 | * can use the value in the 'sh_offset' field |
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168 | * in the section header directly. |
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169 | */ |
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170 | if (e->e_flags & ELF_F_LAYOUT) |
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171 | goto updatedescriptor; |
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172 | else |
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173 | goto computeoffset; |
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174 | } |
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175 | |
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176 | /* |
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177 | * Otherwise, we need to bring in the section's data |
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178 | * from the underlying ELF object. |
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179 | */ |
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180 | if (e->e_cmd != ELF_C_WRITE && elf_getdata(s, NULL) == NULL) |
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181 | return (0); |
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182 | } |
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183 | |
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184 | /* |
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185 | * Loop through the section's data descriptors. |
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186 | */ |
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187 | scn_size = 0L; |
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188 | scn_alignment = 0; |
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189 | STAILQ_FOREACH(d, &s->s_data, d_next) { |
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190 | |
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191 | /* |
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192 | * The data buffer's type is known. |
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193 | */ |
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194 | if (d->d_type >= ELF_T_NUM) { |
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195 | LIBELF_SET_ERROR(DATA, 0); |
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196 | return (0); |
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197 | } |
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198 | |
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199 | /* |
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200 | * The data buffer's version is supported. |
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201 | */ |
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202 | if (d->d_version != e->e_version) { |
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203 | LIBELF_SET_ERROR(VERSION, 0); |
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204 | return (0); |
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205 | } |
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206 | |
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207 | /* |
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208 | * The buffer's alignment is non-zero and a power of |
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209 | * two. |
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210 | */ |
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211 | if ((d_align = d->d_align) == 0 || |
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212 | (d_align & (d_align - 1))) { |
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213 | LIBELF_SET_ERROR(DATA, 0); |
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214 | return (0); |
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215 | } |
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216 | |
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217 | /* |
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218 | * The buffer's size should be a multiple of the |
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219 | * memory size of the underlying type. |
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220 | */ |
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221 | msz = _libelf_msize(d->d_type, ec, e->e_version); |
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222 | if (d->d_size % msz) { |
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223 | LIBELF_SET_ERROR(DATA, 0); |
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224 | return (0); |
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225 | } |
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226 | |
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227 | /* |
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228 | * If the application is controlling layout, then the |
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229 | * d_offset field should be compatible with the |
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230 | * buffer's specified alignment. |
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231 | */ |
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232 | if ((e->e_flags & ELF_F_LAYOUT) && |
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233 | (d->d_off & (d_align - 1))) { |
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234 | LIBELF_SET_ERROR(LAYOUT, 0); |
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235 | return (0); |
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236 | } |
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237 | |
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238 | /* |
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239 | * Compute the section's size. |
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240 | */ |
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241 | if (e->e_flags & ELF_F_LAYOUT) { |
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242 | if ((uint64_t) d->d_off + d->d_size > scn_size) |
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243 | scn_size = d->d_off + d->d_size; |
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244 | } else { |
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245 | scn_size = roundup2(scn_size, d->d_align); |
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246 | d->d_off = scn_size; |
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247 | fsz = _libelf_fsize(d->d_type, ec, d->d_version, |
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248 | d->d_size / msz); |
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249 | scn_size += fsz; |
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250 | } |
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251 | |
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252 | /* |
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253 | * The section's alignment is the maximum alignment |
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254 | * needed for its data buffers. |
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255 | */ |
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256 | if (d_align > scn_alignment) |
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257 | scn_alignment = d_align; |
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258 | } |
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259 | |
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260 | |
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261 | /* |
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262 | * If the application is requesting full control over the |
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263 | * layout of the section, check the section's specified size, |
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264 | * offsets and alignment for sanity. |
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265 | */ |
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266 | if (e->e_flags & ELF_F_LAYOUT) { |
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267 | if (scn_alignment > sh_align || sh_offset % sh_align || |
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268 | sh_size < scn_size) { |
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269 | LIBELF_SET_ERROR(LAYOUT, 0); |
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270 | return (0); |
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271 | } |
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272 | goto updatedescriptor; |
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273 | } |
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274 | |
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275 | /* |
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276 | * Otherwise, compute the values in the section header. |
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277 | * |
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278 | * The section alignment is the maximum alignment for any of |
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279 | * its contained data descriptors. |
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280 | */ |
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281 | if (scn_alignment > sh_align) |
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282 | sh_align = scn_alignment; |
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283 | |
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284 | /* |
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285 | * If the section entry size is zero, try and fill in an |
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286 | * appropriate entry size. Per the elf(5) manual page |
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287 | * sections without fixed-size entries should have their |
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288 | * 'sh_entsize' field set to zero. |
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289 | */ |
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290 | if (sh_entsize == 0 && |
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291 | (sh_entsize = _libelf_fsize(elftype, ec, e->e_version, |
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292 | (size_t) 1)) == 1) |
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293 | sh_entsize = 0; |
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294 | |
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295 | sh_size = scn_size; |
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296 | |
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297 | computeoffset: |
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298 | /* |
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299 | * Compute the new offset for the section based on |
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300 | * the section's alignment needs. |
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301 | */ |
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302 | sh_offset = roundup(rc, sh_align); |
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303 | |
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304 | /* |
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305 | * Update the section header. |
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306 | */ |
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307 | if (ec == ELFCLASS32) { |
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308 | shdr32->sh_addralign = (uint32_t) sh_align; |
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309 | shdr32->sh_entsize = (uint32_t) sh_entsize; |
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310 | shdr32->sh_offset = (uint32_t) sh_offset; |
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311 | shdr32->sh_size = (uint32_t) sh_size; |
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312 | } else { |
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313 | shdr64->sh_addralign = sh_align; |
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314 | shdr64->sh_entsize = sh_entsize; |
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315 | shdr64->sh_offset = sh_offset; |
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316 | shdr64->sh_size = sh_size; |
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317 | } |
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318 | |
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319 | updatedescriptor: |
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320 | /* |
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321 | * Update the section descriptor. |
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322 | */ |
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323 | s->s_size = sh_size; |
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324 | s->s_offset = sh_offset; |
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325 | |
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326 | return (1); |
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327 | } |
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328 | |
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329 | /* |
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330 | * Free a list of extent descriptors. |
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331 | */ |
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332 | |
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333 | static void |
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334 | _libelf_release_extents(struct _Elf_Extent_List *extents) |
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335 | { |
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336 | struct _Elf_Extent *ex; |
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337 | |
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338 | while ((ex = SLIST_FIRST(extents)) != NULL) { |
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339 | SLIST_REMOVE_HEAD(extents, ex_next); |
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340 | free(ex); |
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341 | } |
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342 | } |
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343 | |
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344 | /* |
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345 | * Check if an extent 's' defined by [start..start+size) is free. |
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346 | * This routine assumes that the given extent list is sorted in order |
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347 | * of ascending extent offsets. |
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348 | */ |
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349 | |
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350 | static int |
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351 | _libelf_extent_is_unused(struct _Elf_Extent_List *extents, |
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352 | const uint64_t start, const uint64_t size, struct _Elf_Extent **prevt) |
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353 | { |
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354 | uint64_t tmax, tmin; |
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355 | struct _Elf_Extent *t, *pt; |
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356 | const uint64_t smax = start + size; |
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357 | |
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358 | /* First, look for overlaps with existing extents. */ |
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359 | pt = NULL; |
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360 | SLIST_FOREACH(t, extents, ex_next) { |
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361 | tmin = t->ex_start; |
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362 | tmax = tmin + t->ex_size; |
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363 | |
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364 | if (tmax <= start) { |
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365 | /* |
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366 | * 't' lies entirely before 's': ...| t |...| s |... |
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367 | */ |
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368 | pt = t; |
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369 | continue; |
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370 | } else if (smax <= tmin) { |
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371 | /* |
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372 | * 's' lies entirely before 't', and after 'pt': |
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373 | * ...| pt |...| s |...| t |... |
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374 | */ |
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375 | assert(pt == NULL || |
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376 | pt->ex_start + pt->ex_size <= start); |
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377 | break; |
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378 | } else |
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379 | /* 's' and 't' overlap. */ |
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380 | return (0); |
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381 | } |
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382 | |
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383 | if (prevt) |
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384 | *prevt = pt; |
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385 | return (1); |
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386 | } |
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387 | |
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388 | /* |
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389 | * Insert an extent into the list of extents. |
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390 | */ |
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391 | |
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392 | static int |
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393 | _libelf_insert_extent(struct _Elf_Extent_List *extents, int type, |
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394 | uint64_t start, uint64_t size, void *desc) |
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395 | { |
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396 | struct _Elf_Extent *ex, *prevt; |
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397 | |
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398 | assert(type >= ELF_EXTENT_EHDR && type <= ELF_EXTENT_SHDR); |
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399 | |
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400 | prevt = NULL; |
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401 | |
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402 | /* |
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403 | * If the requested range overlaps with an existing extent, |
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404 | * signal an error. |
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405 | */ |
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406 | if (!_libelf_extent_is_unused(extents, start, size, &prevt)) { |
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407 | LIBELF_SET_ERROR(LAYOUT, 0); |
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408 | return (0); |
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409 | } |
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410 | |
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411 | /* Allocate and fill in a new extent descriptor. */ |
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412 | if ((ex = malloc(sizeof(struct _Elf_Extent))) == NULL) { |
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413 | LIBELF_SET_ERROR(RESOURCE, errno); |
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414 | return (0); |
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415 | } |
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416 | ex->ex_start = start; |
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417 | ex->ex_size = size; |
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418 | ex->ex_desc = desc; |
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419 | ex->ex_type = type; |
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420 | |
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421 | /* Insert the region descriptor into the list. */ |
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422 | if (prevt) |
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423 | SLIST_INSERT_AFTER(prevt, ex, ex_next); |
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424 | else |
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425 | SLIST_INSERT_HEAD(extents, ex, ex_next); |
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426 | return (1); |
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427 | } |
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428 | |
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429 | /* |
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430 | * Recompute section layout. |
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431 | */ |
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432 | |
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433 | static off_t |
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434 | _libelf_resync_sections(Elf *e, off_t rc, struct _Elf_Extent_List *extents) |
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435 | { |
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436 | int ec; |
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437 | Elf_Scn *s; |
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438 | size_t sh_type; |
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439 | |
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440 | ec = e->e_class; |
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441 | |
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442 | /* |
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443 | * Make a pass through sections, computing the extent of each |
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444 | * section. |
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445 | */ |
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446 | STAILQ_FOREACH(s, &e->e_u.e_elf.e_scn, s_next) { |
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447 | if (ec == ELFCLASS32) |
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448 | sh_type = s->s_shdr.s_shdr32.sh_type; |
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449 | else |
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450 | sh_type = s->s_shdr.s_shdr64.sh_type; |
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451 | |
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452 | if (sh_type == SHT_NOBITS || sh_type == SHT_NULL) |
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453 | continue; |
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454 | |
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455 | if (_libelf_compute_section_extents(e, s, rc) == 0) |
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456 | return ((off_t) -1); |
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457 | |
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458 | if (s->s_size == 0) |
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459 | continue; |
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460 | |
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461 | if (!_libelf_insert_extent(extents, ELF_EXTENT_SECTION, |
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462 | s->s_offset, s->s_size, s)) |
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463 | return ((off_t) -1); |
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464 | |
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465 | if ((size_t) rc < s->s_offset + s->s_size) |
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466 | rc = s->s_offset + s->s_size; |
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467 | } |
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468 | |
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469 | return (rc); |
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470 | } |
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471 | |
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472 | /* |
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473 | * Recompute the layout of the ELF object and update the internal data |
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474 | * structures associated with the ELF descriptor. |
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475 | * |
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476 | * Returns the size in bytes the ELF object would occupy in its file |
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477 | * representation. |
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478 | * |
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479 | * After a successful call to this function, the following structures |
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480 | * are updated: |
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481 | * |
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482 | * - The ELF header is updated. |
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483 | * - All extents in the ELF object are sorted in order of ascending |
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484 | * addresses. Sections have their section header table entries |
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485 | * updated. An error is signalled if an overlap was detected among |
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486 | * extents. |
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487 | * - Data descriptors associated with sections are checked for valid |
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488 | * types, offsets and alignment. |
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489 | * |
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490 | * After a resync_elf() successfully returns, the ELF descriptor is |
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491 | * ready for being handed over to _libelf_write_elf(). |
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492 | */ |
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493 | |
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494 | static off_t |
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495 | _libelf_resync_elf(Elf *e, struct _Elf_Extent_List *extents) |
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496 | { |
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497 | int ec, eh_class, eh_type; |
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498 | unsigned int eh_byteorder, eh_version; |
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499 | size_t align, fsz; |
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500 | size_t phnum, shnum; |
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501 | off_t rc, phoff, shoff; |
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502 | void *ehdr, *phdr; |
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503 | Elf32_Ehdr *eh32; |
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504 | Elf64_Ehdr *eh64; |
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505 | |
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506 | rc = 0; |
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507 | |
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508 | ec = e->e_class; |
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509 | |
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510 | assert(ec == ELFCLASS32 || ec == ELFCLASS64); |
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511 | |
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512 | /* |
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513 | * Prepare the EHDR. |
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514 | */ |
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515 | if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) |
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516 | return ((off_t) -1); |
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517 | |
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518 | eh32 = ehdr; |
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519 | eh64 = ehdr; |
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520 | |
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521 | if (ec == ELFCLASS32) { |
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522 | eh_byteorder = eh32->e_ident[EI_DATA]; |
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523 | eh_class = eh32->e_ident[EI_CLASS]; |
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524 | phoff = (uint64_t) eh32->e_phoff; |
---|
525 | shoff = (uint64_t) eh32->e_shoff; |
---|
526 | eh_type = eh32->e_type; |
---|
527 | eh_version = eh32->e_version; |
---|
528 | } else { |
---|
529 | eh_byteorder = eh64->e_ident[EI_DATA]; |
---|
530 | eh_class = eh64->e_ident[EI_CLASS]; |
---|
531 | phoff = eh64->e_phoff; |
---|
532 | shoff = eh64->e_shoff; |
---|
533 | eh_type = eh64->e_type; |
---|
534 | eh_version = eh64->e_version; |
---|
535 | } |
---|
536 | |
---|
537 | if (eh_version == EV_NONE) |
---|
538 | eh_version = EV_CURRENT; |
---|
539 | |
---|
540 | if (eh_version != e->e_version) { /* always EV_CURRENT */ |
---|
541 | LIBELF_SET_ERROR(VERSION, 0); |
---|
542 | return ((off_t) -1); |
---|
543 | } |
---|
544 | |
---|
545 | if (eh_class != e->e_class) { |
---|
546 | LIBELF_SET_ERROR(CLASS, 0); |
---|
547 | return ((off_t) -1); |
---|
548 | } |
---|
549 | |
---|
550 | if (e->e_cmd != ELF_C_WRITE && eh_byteorder != e->e_byteorder) { |
---|
551 | LIBELF_SET_ERROR(HEADER, 0); |
---|
552 | return ((off_t) -1); |
---|
553 | } |
---|
554 | |
---|
555 | shnum = e->e_u.e_elf.e_nscn; |
---|
556 | phnum = e->e_u.e_elf.e_nphdr; |
---|
557 | |
---|
558 | e->e_byteorder = eh_byteorder; |
---|
559 | |
---|
560 | #define INITIALIZE_EHDR(E,EC,V) do { \ |
---|
561 | (E)->e_ident[EI_MAG0] = ELFMAG0; \ |
---|
562 | (E)->e_ident[EI_MAG1] = ELFMAG1; \ |
---|
563 | (E)->e_ident[EI_MAG2] = ELFMAG2; \ |
---|
564 | (E)->e_ident[EI_MAG3] = ELFMAG3; \ |
---|
565 | (E)->e_ident[EI_CLASS] = (EC); \ |
---|
566 | (E)->e_ident[EI_VERSION] = (V); \ |
---|
567 | (E)->e_ehsize = _libelf_fsize(ELF_T_EHDR, (EC), (V), \ |
---|
568 | (size_t) 1); \ |
---|
569 | (E)->e_phentsize = (phnum == 0) ? 0 : _libelf_fsize( \ |
---|
570 | ELF_T_PHDR, (EC), (V), (size_t) 1); \ |
---|
571 | (E)->e_shentsize = _libelf_fsize(ELF_T_SHDR, (EC), (V), \ |
---|
572 | (size_t) 1); \ |
---|
573 | } while (0) |
---|
574 | |
---|
575 | if (ec == ELFCLASS32) |
---|
576 | INITIALIZE_EHDR(eh32, ec, eh_version); |
---|
577 | else |
---|
578 | INITIALIZE_EHDR(eh64, ec, eh_version); |
---|
579 | |
---|
580 | (void) elf_flagehdr(e, ELF_C_SET, ELF_F_DIRTY); |
---|
581 | |
---|
582 | rc += _libelf_fsize(ELF_T_EHDR, ec, eh_version, (size_t) 1); |
---|
583 | |
---|
584 | if (!_libelf_insert_extent(extents, ELF_EXTENT_EHDR, 0, rc, ehdr)) |
---|
585 | return ((off_t) -1); |
---|
586 | |
---|
587 | /* |
---|
588 | * Compute the layout the program header table, if one is |
---|
589 | * present. The program header table needs to be aligned to a |
---|
590 | * `natural' boundary. |
---|
591 | */ |
---|
592 | if (phnum) { |
---|
593 | fsz = _libelf_fsize(ELF_T_PHDR, ec, eh_version, phnum); |
---|
594 | align = _libelf_falign(ELF_T_PHDR, ec); |
---|
595 | |
---|
596 | if (e->e_flags & ELF_F_LAYOUT) { |
---|
597 | /* |
---|
598 | * Check offsets for sanity. |
---|
599 | */ |
---|
600 | if (rc > phoff) { |
---|
601 | LIBELF_SET_ERROR(LAYOUT, 0); |
---|
602 | return ((off_t) -1); |
---|
603 | } |
---|
604 | |
---|
605 | if (phoff % align) { |
---|
606 | LIBELF_SET_ERROR(LAYOUT, 0); |
---|
607 | return ((off_t) -1); |
---|
608 | } |
---|
609 | |
---|
610 | } else |
---|
611 | phoff = roundup(rc, align); |
---|
612 | |
---|
613 | rc = phoff + fsz; |
---|
614 | |
---|
615 | phdr = _libelf_getphdr(e, ec); |
---|
616 | |
---|
617 | if (!_libelf_insert_extent(extents, ELF_EXTENT_PHDR, phoff, |
---|
618 | fsz, phdr)) |
---|
619 | return ((off_t) -1); |
---|
620 | } else |
---|
621 | phoff = 0; |
---|
622 | |
---|
623 | /* |
---|
624 | * Compute the layout of the sections associated with the |
---|
625 | * file. |
---|
626 | */ |
---|
627 | |
---|
628 | if (e->e_cmd != ELF_C_WRITE && |
---|
629 | (e->e_flags & LIBELF_F_SHDRS_LOADED) == 0 && |
---|
630 | _libelf_load_section_headers(e, ehdr) == 0) |
---|
631 | return ((off_t) -1); |
---|
632 | |
---|
633 | if ((rc = _libelf_resync_sections(e, rc, extents)) < 0) |
---|
634 | return ((off_t) -1); |
---|
635 | |
---|
636 | /* |
---|
637 | * Compute the space taken up by the section header table, if |
---|
638 | * one is needed. |
---|
639 | * |
---|
640 | * If ELF_F_LAYOUT has been asserted, the application may have |
---|
641 | * placed the section header table in between existing |
---|
642 | * sections, so the net size of the file need not increase due |
---|
643 | * to the presence of the section header table. |
---|
644 | * |
---|
645 | * If the library is responsible for laying out the object, |
---|
646 | * the section header table is placed after section data. |
---|
647 | */ |
---|
648 | if (shnum) { |
---|
649 | fsz = _libelf_fsize(ELF_T_SHDR, ec, eh_version, shnum); |
---|
650 | align = _libelf_falign(ELF_T_SHDR, ec); |
---|
651 | |
---|
652 | if (e->e_flags & ELF_F_LAYOUT) { |
---|
653 | if (shoff % align) { |
---|
654 | LIBELF_SET_ERROR(LAYOUT, 0); |
---|
655 | return ((off_t) -1); |
---|
656 | } |
---|
657 | } else |
---|
658 | shoff = roundup(rc, align); |
---|
659 | |
---|
660 | if (shoff + fsz > (size_t) rc) |
---|
661 | rc = shoff + fsz; |
---|
662 | |
---|
663 | if (!_libelf_insert_extent(extents, ELF_EXTENT_SHDR, shoff, |
---|
664 | fsz, NULL)) |
---|
665 | return ((off_t) -1); |
---|
666 | } else |
---|
667 | shoff = 0; |
---|
668 | |
---|
669 | /* |
---|
670 | * Set the fields of the Executable Header that could potentially use |
---|
671 | * extended numbering. |
---|
672 | */ |
---|
673 | _libelf_setphnum(e, ehdr, ec, phnum); |
---|
674 | _libelf_setshnum(e, ehdr, ec, shnum); |
---|
675 | |
---|
676 | /* |
---|
677 | * Update the `e_phoff' and `e_shoff' fields if the library is |
---|
678 | * doing the layout. |
---|
679 | */ |
---|
680 | if ((e->e_flags & ELF_F_LAYOUT) == 0) { |
---|
681 | if (ec == ELFCLASS32) { |
---|
682 | eh32->e_phoff = (uint32_t) phoff; |
---|
683 | eh32->e_shoff = (uint32_t) shoff; |
---|
684 | } else { |
---|
685 | eh64->e_phoff = (uint64_t) phoff; |
---|
686 | eh64->e_shoff = (uint64_t) shoff; |
---|
687 | } |
---|
688 | } |
---|
689 | |
---|
690 | return (rc); |
---|
691 | } |
---|
692 | |
---|
693 | /* |
---|
694 | * Write out the contents of an ELF section. |
---|
695 | */ |
---|
696 | |
---|
697 | static size_t |
---|
698 | _libelf_write_scn(Elf *e, char *nf, struct _Elf_Extent *ex) |
---|
699 | { |
---|
700 | int ec; |
---|
701 | size_t fsz, msz, nobjects, rc; |
---|
702 | uint32_t sh_type; |
---|
703 | uint64_t sh_off, sh_size; |
---|
704 | int elftype; |
---|
705 | Elf_Scn *s; |
---|
706 | Elf_Data *d, dst; |
---|
707 | |
---|
708 | assert(ex->ex_type == ELF_EXTENT_SECTION); |
---|
709 | |
---|
710 | s = ex->ex_desc; |
---|
711 | rc = ex->ex_start; |
---|
712 | |
---|
713 | if ((ec = e->e_class) == ELFCLASS32) { |
---|
714 | sh_type = s->s_shdr.s_shdr32.sh_type; |
---|
715 | sh_size = (uint64_t) s->s_shdr.s_shdr32.sh_size; |
---|
716 | } else { |
---|
717 | sh_type = s->s_shdr.s_shdr64.sh_type; |
---|
718 | sh_size = s->s_shdr.s_shdr64.sh_size; |
---|
719 | } |
---|
720 | |
---|
721 | /* |
---|
722 | * Ignore sections that do not allocate space in the file. |
---|
723 | */ |
---|
724 | if (sh_type == SHT_NOBITS || sh_type == SHT_NULL || sh_size == 0) |
---|
725 | return (rc); |
---|
726 | |
---|
727 | elftype = _libelf_xlate_shtype(sh_type); |
---|
728 | assert(elftype >= ELF_T_FIRST && elftype <= ELF_T_LAST); |
---|
729 | |
---|
730 | sh_off = s->s_offset; |
---|
731 | assert(sh_off % _libelf_falign(elftype, ec) == 0); |
---|
732 | |
---|
733 | /* |
---|
734 | * If the section has a `rawdata' descriptor, and the section |
---|
735 | * contents have not been modified, use its contents directly. |
---|
736 | * The `s_rawoff' member contains the offset into the original |
---|
737 | * file, while `s_offset' contains its new location in the |
---|
738 | * destination. |
---|
739 | */ |
---|
740 | |
---|
741 | if (STAILQ_EMPTY(&s->s_data)) { |
---|
742 | |
---|
743 | if ((d = elf_rawdata(s, NULL)) == NULL) |
---|
744 | return ((off_t) -1); |
---|
745 | |
---|
746 | STAILQ_FOREACH(d, &s->s_rawdata, d_next) { |
---|
747 | if ((uint64_t) rc < sh_off + d->d_off) |
---|
748 | (void) memset(nf + rc, |
---|
749 | LIBELF_PRIVATE(fillchar), sh_off + |
---|
750 | d->d_off - rc); |
---|
751 | rc = sh_off + d->d_off; |
---|
752 | |
---|
753 | assert(d->d_buf != NULL); |
---|
754 | assert(d->d_type == ELF_T_BYTE); |
---|
755 | assert(d->d_version == e->e_version); |
---|
756 | |
---|
757 | (void) memcpy(nf + rc, |
---|
758 | e->e_rawfile + s->s_rawoff + d->d_off, d->d_size); |
---|
759 | |
---|
760 | rc += d->d_size; |
---|
761 | } |
---|
762 | |
---|
763 | return (rc); |
---|
764 | } |
---|
765 | |
---|
766 | /* |
---|
767 | * Iterate over the set of data descriptors for this section. |
---|
768 | * The prior call to _libelf_resync_elf() would have setup the |
---|
769 | * descriptors for this step. |
---|
770 | */ |
---|
771 | |
---|
772 | dst.d_version = e->e_version; |
---|
773 | |
---|
774 | STAILQ_FOREACH(d, &s->s_data, d_next) { |
---|
775 | |
---|
776 | msz = _libelf_msize(d->d_type, ec, e->e_version); |
---|
777 | |
---|
778 | if ((uint64_t) rc < sh_off + d->d_off) |
---|
779 | (void) memset(nf + rc, |
---|
780 | LIBELF_PRIVATE(fillchar), sh_off + d->d_off - rc); |
---|
781 | |
---|
782 | rc = sh_off + d->d_off; |
---|
783 | |
---|
784 | assert(d->d_buf != NULL); |
---|
785 | assert(d->d_version == e->e_version); |
---|
786 | assert(d->d_size % msz == 0); |
---|
787 | |
---|
788 | nobjects = d->d_size / msz; |
---|
789 | |
---|
790 | fsz = _libelf_fsize(d->d_type, ec, e->e_version, nobjects); |
---|
791 | |
---|
792 | dst.d_buf = nf + rc; |
---|
793 | dst.d_size = fsz; |
---|
794 | |
---|
795 | if (_libelf_xlate(&dst, d, e->e_byteorder, ec, ELF_TOFILE) == |
---|
796 | NULL) |
---|
797 | return ((off_t) -1); |
---|
798 | |
---|
799 | rc += fsz; |
---|
800 | } |
---|
801 | |
---|
802 | return ((off_t) rc); |
---|
803 | } |
---|
804 | |
---|
805 | /* |
---|
806 | * Write out an ELF Executable Header. |
---|
807 | */ |
---|
808 | |
---|
809 | static off_t |
---|
810 | _libelf_write_ehdr(Elf *e, char *nf, struct _Elf_Extent *ex) |
---|
811 | { |
---|
812 | int ec; |
---|
813 | void *ehdr; |
---|
814 | size_t fsz, msz; |
---|
815 | Elf_Data dst, src; |
---|
816 | |
---|
817 | assert(ex->ex_type == ELF_EXTENT_EHDR); |
---|
818 | assert(ex->ex_start == 0); /* Ehdr always comes first. */ |
---|
819 | |
---|
820 | ec = e->e_class; |
---|
821 | |
---|
822 | ehdr = _libelf_ehdr(e, ec, 0); |
---|
823 | assert(ehdr != NULL); |
---|
824 | |
---|
825 | fsz = _libelf_fsize(ELF_T_EHDR, ec, e->e_version, (size_t) 1); |
---|
826 | msz = _libelf_msize(ELF_T_EHDR, ec, e->e_version); |
---|
827 | |
---|
828 | (void) memset(&dst, 0, sizeof(dst)); |
---|
829 | (void) memset(&src, 0, sizeof(src)); |
---|
830 | |
---|
831 | src.d_buf = ehdr; |
---|
832 | src.d_size = msz; |
---|
833 | src.d_type = ELF_T_EHDR; |
---|
834 | src.d_version = dst.d_version = e->e_version; |
---|
835 | |
---|
836 | dst.d_buf = nf; |
---|
837 | dst.d_size = fsz; |
---|
838 | |
---|
839 | if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, ELF_TOFILE) == |
---|
840 | NULL) |
---|
841 | return ((off_t) -1); |
---|
842 | |
---|
843 | return ((off_t) fsz); |
---|
844 | } |
---|
845 | |
---|
846 | /* |
---|
847 | * Write out an ELF program header table. |
---|
848 | */ |
---|
849 | |
---|
850 | static off_t |
---|
851 | _libelf_write_phdr(Elf *e, char *nf, struct _Elf_Extent *ex) |
---|
852 | { |
---|
853 | int ec; |
---|
854 | void *ehdr; |
---|
855 | Elf32_Ehdr *eh32; |
---|
856 | Elf64_Ehdr *eh64; |
---|
857 | Elf_Data dst, src; |
---|
858 | size_t fsz, phnum; |
---|
859 | uint64_t phoff; |
---|
860 | |
---|
861 | assert(ex->ex_type == ELF_EXTENT_PHDR); |
---|
862 | |
---|
863 | ec = e->e_class; |
---|
864 | ehdr = _libelf_ehdr(e, ec, 0); |
---|
865 | phnum = e->e_u.e_elf.e_nphdr; |
---|
866 | |
---|
867 | assert(phnum > 0); |
---|
868 | |
---|
869 | if (ec == ELFCLASS32) { |
---|
870 | eh32 = (Elf32_Ehdr *) ehdr; |
---|
871 | phoff = (uint64_t) eh32->e_phoff; |
---|
872 | } else { |
---|
873 | eh64 = (Elf64_Ehdr *) ehdr; |
---|
874 | phoff = eh64->e_phoff; |
---|
875 | } |
---|
876 | |
---|
877 | assert(phoff > 0); |
---|
878 | assert(ex->ex_start == phoff); |
---|
879 | assert(phoff % _libelf_falign(ELF_T_PHDR, ec) == 0); |
---|
880 | |
---|
881 | (void) memset(&dst, 0, sizeof(dst)); |
---|
882 | (void) memset(&src, 0, sizeof(src)); |
---|
883 | |
---|
884 | fsz = _libelf_fsize(ELF_T_PHDR, ec, e->e_version, phnum); |
---|
885 | assert(fsz > 0); |
---|
886 | |
---|
887 | src.d_buf = _libelf_getphdr(e, ec); |
---|
888 | src.d_version = dst.d_version = e->e_version; |
---|
889 | src.d_type = ELF_T_PHDR; |
---|
890 | src.d_size = phnum * _libelf_msize(ELF_T_PHDR, ec, |
---|
891 | e->e_version); |
---|
892 | |
---|
893 | dst.d_size = fsz; |
---|
894 | dst.d_buf = nf + ex->ex_start; |
---|
895 | |
---|
896 | if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, ELF_TOFILE) == |
---|
897 | NULL) |
---|
898 | return ((off_t) -1); |
---|
899 | |
---|
900 | return (phoff + fsz); |
---|
901 | } |
---|
902 | |
---|
903 | /* |
---|
904 | * Write out an ELF section header table. |
---|
905 | */ |
---|
906 | |
---|
907 | static off_t |
---|
908 | _libelf_write_shdr(Elf *e, char *nf, struct _Elf_Extent *ex) |
---|
909 | { |
---|
910 | int ec; |
---|
911 | void *ehdr; |
---|
912 | Elf_Scn *scn; |
---|
913 | uint64_t shoff; |
---|
914 | Elf32_Ehdr *eh32; |
---|
915 | Elf64_Ehdr *eh64; |
---|
916 | size_t fsz, nscn; |
---|
917 | Elf_Data dst, src; |
---|
918 | |
---|
919 | assert(ex->ex_type == ELF_EXTENT_SHDR); |
---|
920 | |
---|
921 | ec = e->e_class; |
---|
922 | ehdr = _libelf_ehdr(e, ec, 0); |
---|
923 | nscn = e->e_u.e_elf.e_nscn; |
---|
924 | |
---|
925 | if (ec == ELFCLASS32) { |
---|
926 | eh32 = (Elf32_Ehdr *) ehdr; |
---|
927 | shoff = (uint64_t) eh32->e_shoff; |
---|
928 | } else { |
---|
929 | eh64 = (Elf64_Ehdr *) ehdr; |
---|
930 | shoff = eh64->e_shoff; |
---|
931 | } |
---|
932 | |
---|
933 | assert(nscn > 0); |
---|
934 | assert(shoff % _libelf_falign(ELF_T_SHDR, ec) == 0); |
---|
935 | assert(ex->ex_start == shoff); |
---|
936 | |
---|
937 | (void) memset(&dst, 0, sizeof(dst)); |
---|
938 | (void) memset(&src, 0, sizeof(src)); |
---|
939 | |
---|
940 | src.d_type = ELF_T_SHDR; |
---|
941 | src.d_size = _libelf_msize(ELF_T_SHDR, ec, e->e_version); |
---|
942 | src.d_version = dst.d_version = e->e_version; |
---|
943 | |
---|
944 | fsz = _libelf_fsize(ELF_T_SHDR, ec, e->e_version, (size_t) 1); |
---|
945 | |
---|
946 | STAILQ_FOREACH(scn, &e->e_u.e_elf.e_scn, s_next) { |
---|
947 | if (ec == ELFCLASS32) |
---|
948 | src.d_buf = &scn->s_shdr.s_shdr32; |
---|
949 | else |
---|
950 | src.d_buf = &scn->s_shdr.s_shdr64; |
---|
951 | |
---|
952 | dst.d_size = fsz; |
---|
953 | dst.d_buf = nf + ex->ex_start + scn->s_ndx * fsz; |
---|
954 | |
---|
955 | if (_libelf_xlate(&dst, &src, e->e_byteorder, ec, |
---|
956 | ELF_TOFILE) == NULL) |
---|
957 | return ((off_t) -1); |
---|
958 | } |
---|
959 | |
---|
960 | return (ex->ex_start + nscn * fsz); |
---|
961 | } |
---|
962 | |
---|
963 | /* |
---|
964 | * Write out the file image. |
---|
965 | * |
---|
966 | * The original file could have been mapped in with an ELF_C_RDWR |
---|
967 | * command and the application could have added new content or |
---|
968 | * re-arranged its sections before calling elf_update(). Consequently |
---|
969 | * its not safe to work `in place' on the original file. So we |
---|
970 | * malloc() the required space for the updated ELF object and build |
---|
971 | * the object there and write it out to the underlying file at the |
---|
972 | * end. Note that the application may have opened the underlying file |
---|
973 | * in ELF_C_RDWR and only retrieved/modified a few sections. We take |
---|
974 | * care to avoid translating file sections unnecessarily. |
---|
975 | * |
---|
976 | * Gaps in the coverage of the file by the file's sections will be |
---|
977 | * filled with the fill character set by elf_fill(3). |
---|
978 | */ |
---|
979 | |
---|
980 | static off_t |
---|
981 | _libelf_write_elf(Elf *e, off_t newsize, struct _Elf_Extent_List *extents) |
---|
982 | { |
---|
983 | off_t nrc, rc; |
---|
984 | char *newfile; |
---|
985 | Elf_Scn *scn, *tscn; |
---|
986 | struct _Elf_Extent *ex; |
---|
987 | |
---|
988 | assert(e->e_kind == ELF_K_ELF); |
---|
989 | assert(e->e_cmd != ELF_C_READ); |
---|
990 | assert(e->e_fd >= 0); |
---|
991 | |
---|
992 | if ((newfile = malloc((size_t) newsize)) == NULL) { |
---|
993 | LIBELF_SET_ERROR(RESOURCE, errno); |
---|
994 | return ((off_t) -1); |
---|
995 | } |
---|
996 | |
---|
997 | nrc = rc = 0; |
---|
998 | SLIST_FOREACH(ex, extents, ex_next) { |
---|
999 | |
---|
1000 | /* Fill inter-extent gaps. */ |
---|
1001 | if (ex->ex_start > (size_t) rc) |
---|
1002 | (void) memset(newfile + rc, LIBELF_PRIVATE(fillchar), |
---|
1003 | ex->ex_start - rc); |
---|
1004 | |
---|
1005 | switch (ex->ex_type) { |
---|
1006 | case ELF_EXTENT_EHDR: |
---|
1007 | if ((nrc = _libelf_write_ehdr(e, newfile, ex)) < 0) |
---|
1008 | goto error; |
---|
1009 | break; |
---|
1010 | |
---|
1011 | case ELF_EXTENT_PHDR: |
---|
1012 | if ((nrc = _libelf_write_phdr(e, newfile, ex)) < 0) |
---|
1013 | goto error; |
---|
1014 | break; |
---|
1015 | |
---|
1016 | case ELF_EXTENT_SECTION: |
---|
1017 | if ((nrc = _libelf_write_scn(e, newfile, ex)) < 0) |
---|
1018 | goto error; |
---|
1019 | break; |
---|
1020 | |
---|
1021 | case ELF_EXTENT_SHDR: |
---|
1022 | if ((nrc = _libelf_write_shdr(e, newfile, ex)) < 0) |
---|
1023 | goto error; |
---|
1024 | break; |
---|
1025 | |
---|
1026 | default: |
---|
1027 | assert(0); |
---|
1028 | break; |
---|
1029 | } |
---|
1030 | |
---|
1031 | assert(ex->ex_start + ex->ex_size == (size_t) nrc); |
---|
1032 | assert(rc < nrc); |
---|
1033 | |
---|
1034 | rc = nrc; |
---|
1035 | } |
---|
1036 | |
---|
1037 | assert(rc == newsize); |
---|
1038 | |
---|
1039 | /* |
---|
1040 | * Write out the constructed contents and remap the file in |
---|
1041 | * read-only. |
---|
1042 | */ |
---|
1043 | |
---|
1044 | if (e->e_rawfile && munmap(e->e_rawfile, e->e_rawsize) < 0) { |
---|
1045 | LIBELF_SET_ERROR(IO, errno); |
---|
1046 | goto error; |
---|
1047 | } |
---|
1048 | |
---|
1049 | if (write(e->e_fd, newfile, (size_t) newsize) != newsize || |
---|
1050 | lseek(e->e_fd, (off_t) 0, SEEK_SET) < 0) { |
---|
1051 | LIBELF_SET_ERROR(IO, errno); |
---|
1052 | goto error; |
---|
1053 | } |
---|
1054 | |
---|
1055 | if (e->e_cmd != ELF_C_WRITE) { |
---|
1056 | |
---|
1057 | if (e->e_rawsize > (size_t) newsize && |
---|
1058 | ftruncate(e->e_fd, newsize) < 0) { |
---|
1059 | LIBELF_SET_ERROR(IO, errno); |
---|
1060 | goto error; |
---|
1061 | } |
---|
1062 | |
---|
1063 | if ((e->e_rawfile = mmap(NULL, (size_t) newsize, PROT_READ, |
---|
1064 | MAP_PRIVATE, e->e_fd, (off_t) 0)) == MAP_FAILED) { |
---|
1065 | LIBELF_SET_ERROR(IO, errno); |
---|
1066 | goto error; |
---|
1067 | } |
---|
1068 | e->e_rawsize = newsize; |
---|
1069 | } |
---|
1070 | |
---|
1071 | /* |
---|
1072 | * Reset flags, remove existing section descriptors and |
---|
1073 | * {E,P}HDR pointers so that a subsequent elf_get{e,p}hdr() |
---|
1074 | * and elf_getscn() will function correctly. |
---|
1075 | */ |
---|
1076 | |
---|
1077 | e->e_flags &= ~ELF_F_DIRTY; |
---|
1078 | |
---|
1079 | STAILQ_FOREACH_SAFE(scn, &e->e_u.e_elf.e_scn, s_next, tscn) |
---|
1080 | _libelf_release_scn(scn); |
---|
1081 | |
---|
1082 | if (e->e_class == ELFCLASS32) { |
---|
1083 | free(e->e_u.e_elf.e_ehdr.e_ehdr32); |
---|
1084 | if (e->e_u.e_elf.e_phdr.e_phdr32) |
---|
1085 | free(e->e_u.e_elf.e_phdr.e_phdr32); |
---|
1086 | |
---|
1087 | e->e_u.e_elf.e_ehdr.e_ehdr32 = NULL; |
---|
1088 | e->e_u.e_elf.e_phdr.e_phdr32 = NULL; |
---|
1089 | } else { |
---|
1090 | free(e->e_u.e_elf.e_ehdr.e_ehdr64); |
---|
1091 | if (e->e_u.e_elf.e_phdr.e_phdr64) |
---|
1092 | free(e->e_u.e_elf.e_phdr.e_phdr64); |
---|
1093 | |
---|
1094 | e->e_u.e_elf.e_ehdr.e_ehdr64 = NULL; |
---|
1095 | e->e_u.e_elf.e_phdr.e_phdr64 = NULL; |
---|
1096 | } |
---|
1097 | |
---|
1098 | free(newfile); |
---|
1099 | |
---|
1100 | return (rc); |
---|
1101 | |
---|
1102 | error: |
---|
1103 | free(newfile); |
---|
1104 | |
---|
1105 | return ((off_t) -1); |
---|
1106 | } |
---|
1107 | |
---|
1108 | /* |
---|
1109 | * Update an ELF object. |
---|
1110 | */ |
---|
1111 | |
---|
1112 | off_t |
---|
1113 | elf_update(Elf *e, Elf_Cmd c) |
---|
1114 | { |
---|
1115 | int ec; |
---|
1116 | off_t rc; |
---|
1117 | struct _Elf_Extent_List extents; |
---|
1118 | |
---|
1119 | rc = (off_t) -1; |
---|
1120 | |
---|
1121 | if (e == NULL || e->e_kind != ELF_K_ELF || |
---|
1122 | (c != ELF_C_NULL && c != ELF_C_WRITE)) { |
---|
1123 | LIBELF_SET_ERROR(ARGUMENT, 0); |
---|
1124 | return (rc); |
---|
1125 | } |
---|
1126 | |
---|
1127 | if ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) { |
---|
1128 | LIBELF_SET_ERROR(CLASS, 0); |
---|
1129 | return (rc); |
---|
1130 | } |
---|
1131 | |
---|
1132 | if (e->e_version == EV_NONE) |
---|
1133 | e->e_version = EV_CURRENT; |
---|
1134 | |
---|
1135 | if (c == ELF_C_WRITE && e->e_cmd == ELF_C_READ) { |
---|
1136 | LIBELF_SET_ERROR(MODE, 0); |
---|
1137 | return (rc); |
---|
1138 | } |
---|
1139 | |
---|
1140 | SLIST_INIT(&extents); |
---|
1141 | |
---|
1142 | if ((rc = _libelf_resync_elf(e, &extents)) < 0) |
---|
1143 | goto done; |
---|
1144 | |
---|
1145 | if (c == ELF_C_NULL) |
---|
1146 | goto done; |
---|
1147 | |
---|
1148 | if (e->e_fd < 0) { |
---|
1149 | rc = (off_t) -1; |
---|
1150 | LIBELF_SET_ERROR(SEQUENCE, 0); |
---|
1151 | goto done; |
---|
1152 | } |
---|
1153 | |
---|
1154 | return (_libelf_write_elf(e, rc, &extents)); |
---|
1155 | |
---|
1156 | done: |
---|
1157 | _libelf_release_extents(&extents); |
---|
1158 | return (rc); |
---|
1159 | } |
---|