Mercurial > gnulib
view lib/explicit_bzero.c @ 40212:8da9577294da
unistr/*, uniconv/*: Fix undefined behaviour.
Reported by Jeffrey Walton <noloader@gmail.com>.
* lib/unistr/u-cpy.h (FUNC): Don't invoke memcpy with a zero size.
* lib/unistr/u-cpy-alloc.h (FUNC): Likewise.
* lib/uniconv/u8-conv-from-enc.c (u8_conv_from_encoding): Likewise.
* lib/uniconv/u8-conv-to-enc.c (u8_conv_to_encoding): Likewise.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sat, 09 Mar 2019 00:01:47 +0100 |
parents | b06060465f09 |
children |
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/* Erasure of sensitive data, generic implementation. Copyright (C) 2016-2019 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 <https://www.gnu.org/licenses/>. */ /* An assembler implementation of explicit_bzero can be created as an assembler alias of an optimized bzero implementation. Architecture-specific implementations also need to define __explicit_bzero_chk. */ #if !_LIBC # include <config.h> #endif #include <string.h> #if _LIBC /* glibc-internal users use __explicit_bzero_chk, and explicit_bzero redirects to that. */ # undef explicit_bzero #endif /* Set LEN bytes of S to 0. The compiler will not delete a call to this function, even if S is dead after the call. */ void explicit_bzero (void *s, size_t len) { #ifdef HAVE_EXPLICIT_MEMSET explicit_memset (s, 0, len); #else memset (s, '\0', len); # if defined __GNUC__ && !defined __clang__ /* Compiler barrier. */ asm volatile ("" ::: "memory"); # endif #endif }