diff options
Diffstat (limited to 'contrib/netbsd-tests/lib/libc/arch/i386/exec_prot_support.c')
-rw-r--r-- | contrib/netbsd-tests/lib/libc/arch/i386/exec_prot_support.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/contrib/netbsd-tests/lib/libc/arch/i386/exec_prot_support.c b/contrib/netbsd-tests/lib/libc/arch/i386/exec_prot_support.c new file mode 100644 index 0000000..11a20f5 --- /dev/null +++ b/contrib/netbsd-tests/lib/libc/arch/i386/exec_prot_support.c @@ -0,0 +1,65 @@ +/* $NetBSD: exec_prot_support.c,v 1.1 2011/07/18 23:16:09 jym Exp $ */ + +/*- + * Copyright (c) 2011 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Jean-Yves Migeon. + * + * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. + */ + +#include <sys/cdefs.h> +__RCSID("$NetBSD: exec_prot_support.c,v 1.1 2011/07/18 23:16:09 jym Exp $"); + +#include <stdlib.h> +#include <sys/sysctl.h> + +#include "../../common/exec_prot.h" + +/* + * Support for executable space protection has always been erratic under i386. + * Originally IA-32 can't do per-page execute permission, so it is + * implemented using different executable segments for %cs (code segment). + * This only allows coarse grained protection, especially when memory starts + * being fragmented. + * Later, PAE was introduced together with a NX/XD bit in the page table + * entry to offer per-page permission. + */ +int +exec_prot_support(void) +{ + int pae; + size_t pae_len = sizeof(pae); + + if (sysctlbyname("machdep.pae", &pae, &pae_len, NULL, 0) == -1) + return PARTIAL_XP; + + if (pae == 1) { + if (system("cpuctl identify 0 | grep -q NOX") == 0 || + system("cpuctl identify 0 | grep -q XD") == 0) + return PERPAGE_XP; + } + + return PARTIAL_XP; +} |