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-rw-r--r--debug/explicit_bzero_chk.c44
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diff --git a/debug/explicit_bzero_chk.c b/debug/explicit_bzero_chk.c
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+/* 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)