| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859 |
- /* Stack executability handling for GNU dynamic linker. Linux version.
- Copyright (C) 2003-2019 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 <ldsodefs.h>
- #include <sys/mman.h>
- #include <errno.h>
- #include <libintl.h>
- #include <stdbool.h>
- #include <stackinfo.h>
- #include <sysdep.h>
- extern int __stack_prot attribute_relro attribute_hidden;
- int
- _dl_make_stack_executable (void **stack_endp)
- {
- /* This gives us the highest/lowest page that needs to be changed. */
- uintptr_t page = ((uintptr_t) *stack_endp
- & -(intptr_t) GLRO(dl_pagesize));
- int result = 0;
- if (__builtin_expect (__mprotect ((void *) page, GLRO(dl_pagesize),
- __stack_prot) == 0, 1))
- goto return_success;
- result = errno;
- goto out;
- return_success:
- /* Clear the address. */
- *stack_endp = NULL;
- /* Remember that we changed the permission. */
- GL(dl_stack_flags) |= PF_X;
- out:
- #ifdef check_consistency
- check_consistency ();
- #endif
- return result;
- }
- rtld_hidden_def (_dl_make_stack_executable)
|
