diff options
Diffstat (limited to 'src/libelf/elf_getphdrnum.c')
| -rw-r--r-- | src/libelf/elf_getphdrnum.c | 110 |
1 files changed, 65 insertions, 45 deletions
diff --git a/src/libelf/elf_getphdrnum.c b/src/libelf/elf_getphdrnum.c index edf073ec..63c27fb1 100644 --- a/src/libelf/elf_getphdrnum.c +++ b/src/libelf/elf_getphdrnum.c @@ -1,51 +1,30 @@ /* Return number of program headers in the ELF file. - Copyright (C) 2010 Red Hat, Inc. - This file is part of Red Hat elfutils. + Copyright (C) 2010, 2014 Red Hat, Inc. + This file is part of elfutils. - Red Hat elfutils is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by the - Free Software Foundation; version 2 of the License. + This file is free software; you can redistribute it and/or modify + it under the terms of either - Red Hat elfutils is distributed in the hope that it will be useful, but + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. - You should have received a copy of the GNU General Public License along - with Red Hat elfutils; if not, write to the Free Software Foundation, - Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. - - In addition, as a special exception, Red Hat, Inc. gives You the - additional right to link the code of Red Hat elfutils with code licensed - under any Open Source Initiative certified open source license - (http://www.opensource.org/licenses/index.php) which requires the - distribution of source code with any binary distribution and to - distribute linked combinations of the two. Non-GPL Code permitted under - this exception must only link to the code of Red Hat elfutils through - those well defined interfaces identified in the file named EXCEPTION - found in the source code files (the "Approved Interfaces"). The files - of Non-GPL Code may instantiate templates or use macros or inline - functions from the Approved Interfaces without causing the resulting - work to be covered by the GNU General Public License. Only Red Hat, - Inc. may make changes or additions to the list of Approved Interfaces. - Red Hat's grant of this exception is conditioned upon your not adding - any new exceptions. If you wish to add a new Approved Interface or - exception, please contact Red Hat. You must obey the GNU General Public - License in all respects for all of the Red Hat elfutils code and other - code used in conjunction with Red Hat elfutils except the Non-GPL Code - covered by this exception. If you modify this file, you may extend this - exception to your version of the file, but you are not obligated to do - so. If you do not wish to provide this exception without modification, - you must delete this exception statement from your version and license - this file solely under the GPL without exception. - - Red Hat elfutils is an included package of the Open Invention Network. - An included package of the Open Invention Network is a package for which - Open Invention Network licensees cross-license their patents. No patent - license is granted, either expressly or impliedly, by designation as an - included package. Should you wish to participate in the Open Invention - Network licensing program, please visit www.openinventionnetwork.com - <http://www.openinventionnetwork.com>. */ + You should have received copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see <http://www.gnu.org/licenses/>. */ #ifdef HAVE_CONFIG_H # include <config.h> @@ -83,10 +62,18 @@ __elf_getphdrnum_rdlock (elf, dst) /* If there are no section headers, perhaps this is really just 65536 written without PN_XNUM support. Either that or it's bad data. */ - if (likely (scns->cnt > 0)) - *dst = (elf->class == ELFCLASS32 - ? scns->data[0].shdr.e32->sh_info - : scns->data[0].shdr.e64->sh_info); + if (elf->class == ELFCLASS32) + { + if (likely (scns->cnt > 0 + && elf->state.elf32.scns.data[0].shdr.e32 != NULL)) + *dst = scns->data[0].shdr.e32->sh_info; + } + else + { + if (likely (scns->cnt > 0 + && elf->state.elf64.scns.data[0].shdr.e64 != NULL)) + *dst = scns->data[0].shdr.e64->sh_info; + } } return 0; @@ -110,6 +97,39 @@ elf_getphdrnum (elf, dst) rwlock_rdlock (elf->lock); result = __elf_getphdrnum_rdlock (elf, dst); + + /* Do some sanity checking to make sure phnum and phoff are consistent. */ + Elf64_Off off = (elf->class == ELFCLASS32 + ? elf->state.elf32.ehdr->e_phoff + : elf->state.elf64.ehdr->e_phoff); + if (unlikely (off == 0)) + { + *dst = 0; + goto out; + } + + if (unlikely (off >= elf->maximum_size)) + { + __libelf_seterrno (ELF_E_INVALID_DATA); + result = -1; + goto out; + } + + /* Check for too many sections. */ + size_t phdr_size = (elf->class == ELFCLASS32 + ? sizeof (Elf32_Phdr) : sizeof (Elf64_Phdr)); + if (unlikely (*dst > SIZE_MAX / phdr_size)) + { + __libelf_seterrno (ELF_E_INVALID_DATA); + result = -1; + goto out; + } + + /* Truncated file? Don't return more than can be indexed. */ + if (unlikely (elf->maximum_size - off < *dst * phdr_size)) + *dst = (elf->maximum_size - off) / phdr_size; + +out: rwlock_unlock (elf->lock); return result; |