freebsd-dev/sys/tools/amd64_ia32_vdso.sh
Jessica Clarke 8a6ab0f71f Pre-quote macros passed to .incbin to avoid unwanted substitution
Currently for the MFS, firmware and VDSO template assembly files we pass
the path to include with .incbin unquoted and use __XSTRING within the
assembly file to stringify it. However, __XSTRING doesn't just perform a
single level of expansion, it performs the normal full expansion of the
macro, and so if the path itself happens to tokenise to something that
includes a defined macro in it that will itself be substituted. For
example, with #define MACRO 1, a path like /path/containing/MACRO/in/it
will expand to /path/containing/1/in/it and then, when stringified, end
up as "/path/containing/1/in/it", not the intended string. Normally,
macros have names that start or end witih underscores and are unlikely
to appear in a tokenised path (even if technically they could), but now
that we've switched to GNU C as of commit ec41a96daa ("sys: Switch the
kernel's C standard from C99 to GNU99.") there are a few new macros
defined which don't start or end with underscores: unix, which is always
defined to 1, and i386, which is defined to 1 on i386. The former
probably doesn't appear in user paths in practice, but the latter has
been seen to and is likely quite common in the wild.

Fix this by defining the macro pre-quoted instead of using __XSTRING.
Note that technically we don't need to do this for vdso_wrap.S today as
all the paths passed to it are safe file names with no user-controlled
prefix but we should do it anyway for consistency and robustness against
future changes.

This allows make tinderbox to pass when built with source and object
directories inside ~/path-with-unix, which would otherwise expand to
~/path-with-1 and break.

PR:	272744
Fixes:	ec41a96daa ("sys: Switch the kernel's C standard from C99 to GNU99.")
2023-07-28 05:08:43 +01:00

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#!/bin/sh
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c) 2021 The FreeBSD Foundation
# All rights reserved.
#
# This software was developed by Konstantin Belousov <kib@FreeBSD.org>
# under sponsorship from the FreeBSD Foundation.
#
# 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.
set -e
${CC} -x assembler-with-cpp -DLOCORE -fPIC -nostdinc -c -m32 \
-o ia32_sigtramp.pico -I. -I"${S}" -include opt_global.h \
"${S}"/amd64/ia32/ia32_sigtramp.S
${LD} --shared -Bsymbolic -soname="elf-vdso32.so.1" \
-T "${S}"/conf/vdso_amd64_ia32.ldscript \
--eh-frame-hdr --no-undefined -z rodynamic -z norelro -nmagic \
--hash-style=sysv --fatal-warnings --strip-all \
-o elf-vdso32.so.1 ia32_sigtramp.pico
if [ "$(wc -c elf-vdso32.so.1 | ${AWK} '{print $1}')" -gt 2048 ]
then
echo "elf-vdso32.so.1 too large" 1>&2
exit 1
fi
if [ -n "$(${ELFDUMP} -d elf-vdso32.so.1 | \
${AWK} '/DT_REL.*SZ/{print "RELOCS"}')" ]
then
echo "elf-vdso32.so.1 contains runtime relocations" 1>&2
exit 1
fi
${CC} ${DEBUG} -x assembler-with-cpp -DLOCORE -fPIC -nostdinc -c \
-o elf-vdso32.so.o -I. -I"${S}" -include opt_global.h \
-DVDSO_NAME=elf_vdso32_so_1 -DVDSO_FILE=\"elf-vdso32.so.1\" \
"${S}"/tools/vdso_wrap.S
${NM} -D elf-vdso32.so.1 | ${AWK} \
'/__vdso_ia32_sigcode/{printf "#define VDSO_IA32_SIGCODE_OFFSET 0x%s\n",$1}
/__vdso_freebsd4_ia32_sigcode/{printf "#define VDSO_FREEBSD4_IA32_SIGCODE_OFFSET 0x%s\n",$1}
/__vdso_ia32_osigcode/{printf "#define VDSO_IA32_OSIGCODE_OFFSET 0x%s\n",$1}
/__vdso_lcall_tramp/{printf "#define VDSO_LCALL_TRAMP_OFFSET 0x%s\n",$1}' \
>vdso_ia32_offsets.h