glibc/sysdeps/generic/dl-protected.h

59 lines
2.2 KiB
C

/* Support for STV_PROTECTED visibility. Generic version.
Copyright (C) 2021-2024 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/>. */
#ifndef _DL_PROTECTED_H
#define _DL_PROTECTED_H
static inline void __attribute__ ((always_inline))
_dl_check_protected_symbol (const char *undef_name,
const struct link_map *undef_map,
const ElfW(Sym) *ref,
const struct link_map *map,
int type_class)
{
if (undef_map == NULL || undef_map->l_type != lt_executable)
return;
if (type_class & ELF_RTYPE_CLASS_COPY)
/* Disallow copy relocations in executable against protected
data symbols in a shared object which needs indirect external
access. */
_dl_error_printf ("warning: copy relocation against non-copyable "
"protected symbol `%s' in `%s'\n",
undef_name, map->l_name);
else if ((type_class & ELF_RTYPE_CLASS_PLT) && ref->st_value != 0
&& ref->st_shndx == SHN_UNDEF)
/* Disallow non-zero symbol values of undefined symbols in
executable, which are used as the function pointer, against
protected function symbols in a shared object with indirect
external access. */
_dl_error_printf (
"warning: direct reference to "
"protected function `%s' in `%s' may break pointer equality\n",
undef_name, map->l_name);
else
return;
if (map->l_1_needed & GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS)
_dl_signal_error (
0, map->l_name, undef_name,
N_ ("error due to GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS"));
}
#endif /* _DL_PROTECTED_H */