Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 1 | /* Free resources associated with Elf descriptor. |
| 2 | Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2005 Red Hat, Inc. |
| 3 | Written by Ulrich Drepper <drepper@redhat.com>, 1998. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation, version 2. |
| 8 | |
| 9 | This program is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | GNU General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | along with this program; if not, write to the Free Software Foundation, |
| 16 | Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 17 | |
| 18 | #ifdef HAVE_CONFIG_H |
| 19 | # include <config.h> |
| 20 | #endif |
| 21 | |
| 22 | #include <assert.h> |
| 23 | #include <stddef.h> |
| 24 | #include <stdlib.h> |
| 25 | #include <sys/mman.h> |
| 26 | |
| 27 | #include "libelfP.h" |
| 28 | |
| 29 | |
| 30 | int |
| 31 | elf_end (elf) |
| 32 | Elf *elf; |
| 33 | { |
| 34 | Elf *parent; |
| 35 | |
| 36 | if (elf == NULL) |
| 37 | /* This is allowed and is a no-op. */ |
| 38 | return 0; |
| 39 | |
| 40 | /* Make sure we are alone. */ |
| 41 | rwlock_wrlock (elf->lock); |
| 42 | |
| 43 | if (elf->ref_count != 0 && --elf->ref_count != 0) |
| 44 | { |
| 45 | /* Not yet the last activation. */ |
| 46 | int result = elf->ref_count; |
| 47 | rwlock_unlock (elf->lock); |
| 48 | return result; |
| 49 | } |
| 50 | |
| 51 | if (elf->kind == ELF_K_AR) |
| 52 | { |
| 53 | /* We cannot remove the descriptor now since we still have some |
| 54 | descriptors which depend on it. But we can free the archive |
| 55 | symbol table since this is only available via the archive ELF |
| 56 | descriptor. The long name table cannot be freed yet since |
| 57 | the archive headers for the ELF files in the archive point |
| 58 | into this array. */ |
| 59 | free (elf->state.ar.ar_sym); |
| 60 | elf->state.ar.ar_sym = NULL; |
| 61 | |
| 62 | if (elf->state.ar.children != NULL) |
| 63 | return 0; |
| 64 | } |
| 65 | |
| 66 | /* Remove this structure from the children list. */ |
| 67 | parent = elf->parent; |
| 68 | if (parent != NULL) |
| 69 | { |
| 70 | /* This is tricky. Lock must be acquire from the father to |
| 71 | the child but here we already have the child lock. We |
| 72 | solve this problem by giving free the child lock. The |
| 73 | state of REF_COUNT==0 is handled all over the library, so |
| 74 | this should be ok. */ |
| 75 | rwlock_unlock (elf->lock); |
| 76 | rwlock_rdlock (parent->lock); |
| 77 | rwlock_wrlock (elf->lock); |
| 78 | |
| 79 | if (parent->state.ar.children == elf) |
| 80 | parent->state.ar.children = elf->next; |
| 81 | else |
| 82 | { |
| 83 | struct Elf *child = parent->state.ar.children; |
| 84 | |
| 85 | while (child->next != elf) |
| 86 | child = child->next; |
| 87 | |
| 88 | child->next = elf->next; |
| 89 | } |
| 90 | |
| 91 | rwlock_unlock (parent->lock); |
| 92 | } |
| 93 | |
| 94 | /* This was the last activation. Free all resources. */ |
| 95 | switch (elf->kind) |
| 96 | { |
| 97 | case ELF_K_AR: |
| 98 | if (elf->state.ar.long_names != NULL) |
| 99 | free (elf->state.ar.long_names); |
| 100 | break; |
| 101 | |
| 102 | case ELF_K_ELF: |
| 103 | { |
| 104 | Elf_ScnList *list = (elf->class == ELFCLASS32 |
| 105 | || (offsetof (struct Elf, state.elf32.scns) |
| 106 | == offsetof (struct Elf, state.elf64.scns)) |
| 107 | ? &elf->state.elf32.scns |
| 108 | : &elf->state.elf64.scns); |
| 109 | |
| 110 | do |
| 111 | { |
| 112 | /* Free all separately allocated section headers. */ |
| 113 | size_t cnt = list->max; |
| 114 | |
| 115 | while (cnt-- > 0) |
| 116 | { |
| 117 | /* These pointers can be NULL; it's safe to use |
| 118 | 'free' since it will check for this. */ |
| 119 | Elf_Scn *scn = &list->data[cnt]; |
| 120 | Elf_Data_List *runp; |
| 121 | |
| 122 | if ((scn->shdr_flags & ELF_F_MALLOCED) != 0) |
| 123 | /* It doesn't matter which pointer. */ |
| 124 | free (scn->shdr.e32); |
| 125 | |
| 126 | /* If the file has the same byte order and the |
| 127 | architecture doesn't require overly stringent |
| 128 | alignment the raw data buffer is the same as the |
| 129 | one used for presenting to the caller. */ |
| 130 | if (scn->data_base != scn->rawdata_base) |
| 131 | free (scn->data_base); |
| 132 | |
| 133 | /* The section data is allocated if we couldn't mmap |
| 134 | the file. */ |
| 135 | if (elf->map_address == NULL) |
| 136 | free (scn->rawdata_base); |
| 137 | |
| 138 | /* Free the list of data buffers for the section. |
| 139 | We don't free the buffers themselves since this |
| 140 | is the users job. */ |
| 141 | runp = scn->data_list.next; |
| 142 | while (runp != NULL) |
| 143 | { |
| 144 | Elf_Data_List *oldp = runp; |
| 145 | runp = runp->next; |
| 146 | if ((oldp->flags & ELF_F_MALLOCED) != 0) |
| 147 | free (oldp); |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | /* Free the memory for the array. */ |
| 152 | Elf_ScnList *oldp = list; |
| 153 | list = list->next; |
| 154 | assert (list == NULL || oldp->cnt == oldp->max); |
| 155 | if (oldp != (elf->class == ELFCLASS32 |
| 156 | || (offsetof (struct Elf, state.elf32.scns) |
| 157 | == offsetof (struct Elf, state.elf64.scns)) |
| 158 | ? &elf->state.elf32.scns |
| 159 | : &elf->state.elf64.scns)) |
| 160 | free (oldp); |
| 161 | } |
| 162 | while (list != NULL); |
| 163 | } |
| 164 | |
| 165 | /* Free the section header. */ |
| 166 | if (elf->state.elf.shdr_malloced != 0) |
| 167 | free (elf->class == ELFCLASS32 |
| 168 | || (offsetof (struct Elf, state.elf32.shdr) |
| 169 | == offsetof (struct Elf, state.elf64.shdr)) |
| 170 | ? (void *) elf->state.elf32.shdr |
| 171 | : (void *) elf->state.elf64.shdr); |
| 172 | |
| 173 | /* Free the program header. */ |
| 174 | if ((elf->state.elf.phdr_flags & ELF_F_MALLOCED) != 0) |
| 175 | free (elf->class == ELFCLASS32 |
| 176 | || (offsetof (struct Elf, state.elf32.phdr) |
| 177 | == offsetof (struct Elf, state.elf64.phdr)) |
| 178 | ? (void *) elf->state.elf32.phdr |
| 179 | : (void *) elf->state.elf64.phdr); |
| 180 | break; |
| 181 | |
| 182 | default: |
| 183 | break; |
| 184 | } |
| 185 | |
| 186 | if (elf->map_address != NULL && parent == NULL) |
| 187 | { |
| 188 | /* The file was read or mapped for this descriptor. */ |
| 189 | if ((elf->flags & ELF_F_MALLOCED) != 0) |
| 190 | free (elf->map_address); |
| 191 | else if ((elf->flags & ELF_F_MMAPPED) != 0) |
| 192 | munmap (elf->map_address, elf->maximum_size); |
| 193 | } |
| 194 | |
| 195 | rwlock_fini (elf->lock); |
| 196 | |
| 197 | /* Finally the descriptor itself. */ |
| 198 | free (elf); |
| 199 | |
| 200 | return (parent != NULL && parent->ref_count == 0 |
| 201 | ? INTUSE(elf_end) (parent) : 0); |
| 202 | } |
| 203 | INTDEF(elf_end) |