freebsd-dev/lib/libc/include/errlst.h
Jilles Tjoelker e73151eb82 libc: Always use our own copy of sys_errlist and sys_nerr (.so only).
This ensures strerror() and friends continue to work correctly even if a
(non-PIE) executable linked against an older libc imports sys_errlist (which
causes sys_errlist to refer to the executable's copy with a size fixed when
that executable was linked).

The executable's use of sys_errlist remains broken because it uses the
current value of sys_nerr and may access past the bounds of the array.

Different from the message "Using sys_errlist from executables is not
ABI-stable" on freebsd-arch, this change does not affect the static library.
There seems no reason to prevent overriding the error messages in the static
library.
2013-08-31 22:32:42 +00:00

44 lines
1.7 KiB
C

/*-
* Copyright (c) 2013 Jilles Tjoelker
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __ERRLST_H__
#define __ERRLST_H__
#include <sys/cdefs.h>
#ifdef PIC
/* If the main executable imports these, do not use its copy from libc.so. */
extern const char *const __hidden_sys_errlist[] __hidden;
extern const int __hidden_sys_nerr __hidden;
#else
#define __hidden_sys_errlist sys_errlist
#define __hidden_sys_nerr sys_nerr
#endif
#endif /* __ERRLST_H__ */