mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
581c785bf3
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
120 lines
3.3 KiB
C
120 lines
3.3 KiB
C
/* Stack executability handling for GNU dynamic linker. Linux version.
|
|
Copyright (C) 2003-2022 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <errno.h>
|
|
#include <ldsodefs.h>
|
|
#include <libintl.h>
|
|
#include <list.h>
|
|
#include <pthreadP.h>
|
|
#include <stackinfo.h>
|
|
#include <stdbool.h>
|
|
#include <sys/mman.h>
|
|
#include <sysdep.h>
|
|
#include <unistd.h>
|
|
|
|
extern int __stack_prot attribute_relro attribute_hidden;
|
|
|
|
static int
|
|
make_main_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;
|
|
}
|
|
|
|
int
|
|
_dl_make_stacks_executable (void **stack_endp)
|
|
{
|
|
/* First the main thread's stack. */
|
|
int err = make_main_stack_executable (stack_endp);
|
|
if (err != 0)
|
|
return err;
|
|
|
|
lll_lock (GL (dl_stack_cache_lock), LLL_PRIVATE);
|
|
|
|
list_t *runp;
|
|
list_for_each (runp, &GL (dl_stack_used))
|
|
{
|
|
err = __nptl_change_stack_perm (list_entry (runp, struct pthread, list));
|
|
if (err != 0)
|
|
break;
|
|
}
|
|
|
|
/* Also change the permission for the currently unused stacks. This
|
|
might be wasted time but better spend it here than adding a check
|
|
in the fast path. */
|
|
if (err == 0)
|
|
list_for_each (runp, &GL (dl_stack_cache))
|
|
{
|
|
err = __nptl_change_stack_perm (list_entry (runp, struct pthread,
|
|
list));
|
|
if (err != 0)
|
|
break;
|
|
}
|
|
|
|
lll_unlock (GL (dl_stack_cache_lock), LLL_PRIVATE);
|
|
|
|
return err;
|
|
}
|
|
|
|
int
|
|
__nptl_change_stack_perm (struct pthread *pd)
|
|
{
|
|
#ifdef NEED_SEPARATE_REGISTER_STACK
|
|
size_t pagemask = __getpagesize () - 1;
|
|
void *stack = (pd->stackblock
|
|
+ (((((pd->stackblock_size - pd->guardsize) / 2)
|
|
& pagemask) + pd->guardsize) & pagemask));
|
|
size_t len = pd->stackblock + pd->stackblock_size - stack;
|
|
#elif _STACK_GROWS_DOWN
|
|
void *stack = pd->stackblock + pd->guardsize;
|
|
size_t len = pd->stackblock_size - pd->guardsize;
|
|
#elif _STACK_GROWS_UP
|
|
void *stack = pd->stackblock;
|
|
size_t len = (uintptr_t) pd - pd->guardsize - (uintptr_t) pd->stackblock;
|
|
#else
|
|
# error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
|
|
#endif
|
|
if (__mprotect (stack, len, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
|
|
return errno;
|
|
|
|
return 0;
|
|
}
|
|
rtld_hidden_def (__nptl_change_stack_perm)
|