| /* Generic implementation of __explicit_bzero_chk. |
| Copyright (C) 1991-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Torbjorn Granlund (tege@sics.se). |
| |
| 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/>. */ |
| |
| /* This is the generic definition of __explicit_bzero_chk. The |
| __explicit_bzero_chk symbol is used as the implementation of |
| explicit_bzero throughout glibc. If this file is overriden by an |
| architecture, both __explicit_bzero_chk and |
| __explicit_bzero_chk_internal have to be defined (the latter not as |
| an IFUNC). */ |
| |
| #include <string.h> |
| |
| void |
| __explicit_bzero_chk (void *dst, size_t len, size_t dstlen) |
| { |
| /* Inline __memset_chk to avoid a PLT reference to __memset_chk. */ |
| if (__glibc_unlikely (dstlen < len)) |
| __chk_fail (); |
| memset (dst, '\0', len); |
| /* Compiler barrier. */ |
| asm volatile ("" ::: "memory"); |
| } |
| |
| /* libc-internal references use the hidden |
| __explicit_bzero_chk_internal symbol. This is necessary if |
| __explicit_bzero_chk is implemented as an IFUNC because some |
| targets do not support hidden references to IFUNC symbols. */ |
| strong_alias (__explicit_bzero_chk, __explicit_bzero_chk_internal) |