hush/util-linux/setarch.c
Denys Vlasenko f2ccefb946 setarch: add support for '-R' (disable randomization)
This commit adds support for the -R flag of setarch, which disables
randomization of the virtual address space.

function                                             old     new   delta
setarch_main                                         115     150     +35
packed_usage                                       30664   30651     -13

Signed-off-by: Jan Heylen <heyleke@gmail.com>
Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-19 23:26:50 +02:00

86 lines
2.5 KiB
C

/* vi: set sw=4 ts=4: */
/*
* linux32/linux64 allows for changing uname emulation.
*
* Copyright 2002 Andi Kleen, SuSE Labs.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config SETARCH
//config: bool "setarch"
//config: default y
//config: select PLATFORM_LINUX
//config: help
//config: The linux32 utility is used to create a 32bit environment for the
//config: specified program (usually a shell). It only makes sense to have
//config: this util on a system that supports both 64bit and 32bit userland
//config: (like amd64/x86, ppc64/ppc, sparc64/sparc, etc...).
//applet:IF_SETARCH(APPLET(setarch, BB_DIR_BIN, BB_SUID_DROP))
//applet:IF_SETARCH(APPLET_ODDNAME(linux32, setarch, BB_DIR_BIN, BB_SUID_DROP, linux32))
//applet:IF_SETARCH(APPLET_ODDNAME(linux64, setarch, BB_DIR_BIN, BB_SUID_DROP, linux64))
//kbuild:lib-$(CONFIG_SETARCH) += setarch.o
//usage:#define setarch_trivial_usage
//usage: "PERSONALITY [-R] PROG ARGS"
//usage:#define setarch_full_usage "\n\n"
//usage: "PERSONALITY may be:"
//usage: "\n"" linux32 Set 32bit uname emulation"
//usage: "\n"" linux64 Set 64bit uname emulation"
//usage: "\n"
//usage: "\n"" -R Disable address space randomization"
//usage:
//usage:#define linux32_trivial_usage NOUSAGE_STR
//usage:#define linux32_full_usage ""
//usage:
//usage:#define linux64_trivial_usage NOUSAGE_STR
//usage:#define linux64_full_usage ""
#include "libbb.h"
#include <sys/personality.h>
#ifndef ADDR_NO_RANDOMIZE
# define ADDR_NO_RANDOMIZE 0x0040000
#endif
int setarch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int setarch_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opts;
unsigned long pers;
/* Figure out what personality we are supposed to switch to ...
* we can be invoked as either:
* argv[0],argv[1] == "setarch","personality"
* argv[0] == "personality"
*/
if (ENABLE_SETARCH && applet_name[0] == 's'
&& argv[1] && is_prefixed_with(argv[1], "linux")
) {
applet_name = argv[1];
argv++;
}
if (applet_name[5] == '6') /* linux64 */
pers = PER_LINUX;
else if (applet_name[5] == '3') /* linux32 */
pers = PER_LINUX32;
else
bb_show_usage();
opts = getopt32(argv, "+R"); /* '+': stop at first non-option */
if (opts)
pers |= ADDR_NO_RANDOMIZE;
/* Try to set personality */
if (personality(pers) < 0)
bb_perror_msg_and_die("personality(0x%lx)", pers);
argv += optind;
if (!argv[0])
(--argv)[0] = (char*)"/bin/sh";
/* Try to execute the program */
BB_EXECVP_or_die(argv);
}