1 /* Free resources associated with Elf descriptor. 2 Copyright (C) 1998,1999,2000,2001,2002,2004,2005,2007 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 Written by Ulrich Drepper <drepper (at) redhat.com>, 1998. 5 6 Red Hat elfutils is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by the 8 Free Software Foundation; version 2 of the License. 9 10 Red Hat elfutils is distributed in the hope that it will be useful, but 11 WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 General Public License for more details. 14 15 You should have received a copy of the GNU General Public License along 16 with Red Hat elfutils; if not, write to the Free Software Foundation, 17 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 18 19 In addition, as a special exception, Red Hat, Inc. gives You the 20 additional right to link the code of Red Hat elfutils with code licensed 21 under any Open Source Initiative certified open source license 22 (http://www.opensource.org/licenses/index.php) which requires the 23 distribution of source code with any binary distribution and to 24 distribute linked combinations of the two. Non-GPL Code permitted under 25 this exception must only link to the code of Red Hat elfutils through 26 those well defined interfaces identified in the file named EXCEPTION 27 found in the source code files (the "Approved Interfaces"). The files 28 of Non-GPL Code may instantiate templates or use macros or inline 29 functions from the Approved Interfaces without causing the resulting 30 work to be covered by the GNU General Public License. Only Red Hat, 31 Inc. may make changes or additions to the list of Approved Interfaces. 32 Red Hat's grant of this exception is conditioned upon your not adding 33 any new exceptions. If you wish to add a new Approved Interface or 34 exception, please contact Red Hat. You must obey the GNU General Public 35 License in all respects for all of the Red Hat elfutils code and other 36 code used in conjunction with Red Hat elfutils except the Non-GPL Code 37 covered by this exception. If you modify this file, you may extend this 38 exception to your version of the file, but you are not obligated to do 39 so. If you do not wish to provide this exception without modification, 40 you must delete this exception statement from your version and license 41 this file solely under the GPL without exception. 42 43 Red Hat elfutils is an included package of the Open Invention Network. 44 An included package of the Open Invention Network is a package for which 45 Open Invention Network licensees cross-license their patents. No patent 46 license is granted, either expressly or impliedly, by designation as an 47 included package. Should you wish to participate in the Open Invention 48 Network licensing program, please visit www.openinventionnetwork.com 49 <http://www.openinventionnetwork.com>. */ 50 51 #ifdef HAVE_CONFIG_H 52 # include <config.h> 53 #endif 54 55 #include <assert.h> 56 #include <stddef.h> 57 #include <stdlib.h> 58 #include <sys/mman.h> 59 60 #include "libelfP.h" 61 62 63 int 64 elf_end (elf) 65 Elf *elf; 66 { 67 Elf *parent; 68 69 if (elf == NULL) 70 /* This is allowed and is a no-op. */ 71 return 0; 72 73 /* Make sure we are alone. */ 74 rwlock_wrlock (elf->lock); 75 76 if (elf->ref_count != 0 && --elf->ref_count != 0) 77 { 78 /* Not yet the last activation. */ 79 int result = elf->ref_count; 80 rwlock_unlock (elf->lock); 81 return result; 82 } 83 84 if (elf->kind == ELF_K_AR) 85 { 86 /* We cannot remove the descriptor now since we still have some 87 descriptors which depend on it. But we can free the archive 88 symbol table since this is only available via the archive ELF 89 descriptor. The long name table cannot be freed yet since 90 the archive headers for the ELF files in the archive point 91 into this array. */ 92 if (elf->state.ar.ar_sym != (Elf_Arsym *) -1l) 93 free (elf->state.ar.ar_sym); 94 elf->state.ar.ar_sym = NULL; 95 96 if (elf->state.ar.children != NULL) 97 return 0; 98 } 99 100 /* Remove this structure from the children list. */ 101 parent = elf->parent; 102 if (parent != NULL) 103 { 104 /* This is tricky. Lock must be acquire from the father to 105 the child but here we already have the child lock. We 106 solve this problem by giving free the child lock. The 107 state of REF_COUNT==0 is handled all over the library, so 108 this should be ok. */ 109 rwlock_unlock (elf->lock); 110 rwlock_rdlock (parent->lock); 111 rwlock_wrlock (elf->lock); 112 113 if (parent->state.ar.children == elf) 114 parent->state.ar.children = elf->next; 115 else 116 { 117 struct Elf *child = parent->state.ar.children; 118 119 while (child->next != elf) 120 child = child->next; 121 122 child->next = elf->next; 123 } 124 125 rwlock_unlock (parent->lock); 126 } 127 128 /* This was the last activation. Free all resources. */ 129 switch (elf->kind) 130 { 131 case ELF_K_AR: 132 if (elf->state.ar.long_names != NULL) 133 free (elf->state.ar.long_names); 134 break; 135 136 case ELF_K_ELF: 137 { 138 Elf_Data_Chunk *rawchunks 139 = (elf->class == ELFCLASS32 140 || (offsetof (struct Elf, state.elf32.rawchunks) 141 == offsetof (struct Elf, state.elf64.rawchunks)) 142 ? elf->state.elf32.rawchunks 143 : elf->state.elf64.rawchunks); 144 while (rawchunks != NULL) 145 { 146 Elf_Data_Chunk *next = rawchunks->next; 147 if (rawchunks->dummy_scn.flags & ELF_F_MALLOCED) 148 free (rawchunks->data.d.d_buf); 149 free (rawchunks); 150 rawchunks = next; 151 } 152 153 Elf_ScnList *list = (elf->class == ELFCLASS32 154 || (offsetof (struct Elf, state.elf32.scns) 155 == offsetof (struct Elf, state.elf64.scns)) 156 ? &elf->state.elf32.scns 157 : &elf->state.elf64.scns); 158 159 do 160 { 161 /* Free all separately allocated section headers. */ 162 size_t cnt = list->max; 163 164 while (cnt-- > 0) 165 { 166 /* These pointers can be NULL; it's safe to use 167 'free' since it will check for this. */ 168 Elf_Scn *scn = &list->data[cnt]; 169 Elf_Data_List *runp; 170 171 if ((scn->shdr_flags & ELF_F_MALLOCED) != 0) 172 /* It doesn't matter which pointer. */ 173 free (scn->shdr.e32); 174 175 /* If the file has the same byte order and the 176 architecture doesn't require overly stringent 177 alignment the raw data buffer is the same as the 178 one used for presenting to the caller. */ 179 if (scn->data_base != scn->rawdata_base) 180 free (scn->data_base); 181 182 /* The section data is allocated if we couldn't mmap 183 the file. */ 184 if (elf->map_address == NULL) 185 free (scn->rawdata_base); 186 187 /* Free the list of data buffers for the section. 188 We don't free the buffers themselves since this 189 is the users job. */ 190 runp = scn->data_list.next; 191 while (runp != NULL) 192 { 193 Elf_Data_List *oldp = runp; 194 runp = runp->next; 195 if ((oldp->flags & ELF_F_MALLOCED) != 0) 196 free (oldp); 197 } 198 } 199 200 /* Free the memory for the array. */ 201 Elf_ScnList *oldp = list; 202 list = list->next; 203 assert (list == NULL || oldp->cnt == oldp->max); 204 if (oldp != (elf->class == ELFCLASS32 205 || (offsetof (struct Elf, state.elf32.scns) 206 == offsetof (struct Elf, state.elf64.scns)) 207 ? &elf->state.elf32.scns 208 : &elf->state.elf64.scns)) 209 free (oldp); 210 } 211 while (list != NULL); 212 } 213 214 /* Free the section header. */ 215 if (elf->state.elf.shdr_malloced != 0) 216 free (elf->class == ELFCLASS32 217 || (offsetof (struct Elf, state.elf32.shdr) 218 == offsetof (struct Elf, state.elf64.shdr)) 219 ? (void *) elf->state.elf32.shdr 220 : (void *) elf->state.elf64.shdr); 221 222 /* Free the program header. */ 223 if ((elf->state.elf.phdr_flags & ELF_F_MALLOCED) != 0) 224 free (elf->class == ELFCLASS32 225 || (offsetof (struct Elf, state.elf32.phdr) 226 == offsetof (struct Elf, state.elf64.phdr)) 227 ? (void *) elf->state.elf32.phdr 228 : (void *) elf->state.elf64.phdr); 229 break; 230 231 default: 232 break; 233 } 234 235 if (elf->map_address != NULL && parent == NULL) 236 { 237 /* The file was read or mapped for this descriptor. */ 238 if ((elf->flags & ELF_F_MALLOCED) != 0) 239 free (elf->map_address); 240 else if ((elf->flags & ELF_F_MMAPPED) != 0) 241 munmap (elf->map_address, elf->maximum_size); 242 } 243 244 rwlock_fini (elf->lock); 245 246 /* Finally the descriptor itself. */ 247 free (elf); 248 249 return (parent != NULL && parent->ref_count == 0 250 ? INTUSE(elf_end) (parent) : 0); 251 } 252 INTDEF(elf_end) 253