mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 16:50:07 +00:00
98bb2f1cd2
* sysdeps/generic/dl-osinfo.h (_dl_setup_stack_chk_guard): Fix masking out of the most significant byte of random value used. * sysdeps/unix/sysv/linux/dl-osinfo.h (_dl_setup_stack_chk_guard): Fix coding style in previous change.
60 lines
1.8 KiB
C
60 lines
1.8 KiB
C
/* Operating system specific code for generic dynamic loader functions.
|
|
Copyright (C) 2009, 2011 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <endian.h>
|
|
#include <stdint.h>
|
|
|
|
static inline uintptr_t __attribute__ ((always_inline))
|
|
_dl_setup_stack_chk_guard (void *dl_random)
|
|
{
|
|
union
|
|
{
|
|
uintptr_t num;
|
|
unsigned char bytes[sizeof (uintptr_t)];
|
|
} ret = { 0 };
|
|
|
|
if (dl_random == NULL)
|
|
{
|
|
ret.bytes[sizeof (ret) - 1] = 255;
|
|
ret.bytes[sizeof (ret) - 2] = '\n';
|
|
}
|
|
else
|
|
{
|
|
memcpy (ret.bytes, dl_random, sizeof (ret));
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
ret.num &= ~(uintptr_t) 0xff;
|
|
#elif BYTE_ORDER == BIG_ENDIAN
|
|
ret.num &= ~((uintptr_t) 0xff << (8 * (sizeof (ret) - 1)));
|
|
#else
|
|
# error "BYTE_ORDER unknown"
|
|
#endif
|
|
}
|
|
return ret.num;
|
|
}
|
|
|
|
static inline uintptr_t __attribute__ ((always_inline))
|
|
_dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard)
|
|
{
|
|
uintptr_t ret;
|
|
if (dl_random == NULL)
|
|
ret = stack_chk_guard;
|
|
else
|
|
memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));
|
|
return ret;
|
|
}
|