NetBSD/sys/kern/exec_elf_common.c

105 lines
4.0 KiB
C

/* $NetBSD: exec_elf_common.c,v 1.16 2002/11/17 22:53:46 chs Exp $ */
/*-
* Copyright (c) 1994 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* 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>
__KERNEL_RCSID(0, "$NetBSD: exec_elf_common.c,v 1.16 2002/11/17 22:53:46 chs Exp $");
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/exec.h>
#include <sys/exec_elf.h>
#include <sys/resourcevar.h>
/*
* exec_elf_setup_stack(): Set up the stack segment for an elf
* executable.
*
* Note that the ep_ssize parameter must be set to be the current stack
* limit; this is adjusted in the body of execve() to yield the
* appropriate stack segment usage once the argument length is
* calculated.
*
* This function returns an int for uniformity with other (future) formats'
* stack setup functions. They might have errors to return.
*/
int
exec_elf_setup_stack(struct proc *p, struct exec_package *epp)
{
u_long max_stack_size;
u_long access_linear_min, access_size;
u_long noaccess_linear_min, noaccess_size;
#ifndef USRSTACK32
#define USRSTACK32 (0x00000000ffffffffL&~PGOFSET)
#endif
if (epp->ep_flags & EXEC_32) {
epp->ep_minsaddr = USRSTACK32;
max_stack_size = MAXSSIZ;
} else {
epp->ep_minsaddr = USRSTACK;
max_stack_size = MAXSSIZ;
}
epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
max_stack_size);
epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur;
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*/
access_size = epp->ep_ssize;
access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
noaccess_size = max_stack_size - access_size;
noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
access_size), noaccess_size);
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
noaccess_linear_min, NULLVP, 0, VM_PROT_NONE);
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
access_linear_min, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return 0;
}