diff options
Diffstat (limited to 'debug/explicit_bzero_chk.c')
-rw-r--r-- | debug/explicit_bzero_chk.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/debug/explicit_bzero_chk.c b/debug/explicit_bzero_chk.c new file mode 100644 index 0000000000..fb13a7f4b6 --- /dev/null +++ b/debug/explicit_bzero_chk.c @@ -0,0 +1,44 @@ +/* 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) |