linux_exec.c revision 1.44
1/*	$NetBSD: linux_exec.c,v 1.44 2000/12/11 05:29:01 mycroft Exp $	*/
2
3/*-
4 * Copyright (c) 1994, 1995, 1998, 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas, Frank van der Linden, Eric Haszlakiewicz and
9 * Thor Lancelot Simon.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *        This product includes software developed by the NetBSD
22 *        Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 *    contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/kernel.h>
43#include <sys/proc.h>
44#include <sys/malloc.h>
45#include <sys/namei.h>
46#include <sys/vnode.h>
47#include <sys/mount.h>
48#include <sys/exec.h>
49#include <sys/exec_elf.h>
50
51#include <sys/mman.h>
52#include <sys/syscallargs.h>
53
54#include <machine/cpu.h>
55#include <machine/reg.h>
56
57#include <compat/linux/common/linux_types.h>
58#include <compat/linux/common/linux_signal.h>
59#include <compat/linux/common/linux_util.h>
60#include <compat/linux/common/linux_exec.h>
61#include <compat/linux/common/linux_machdep.h>
62
63#include <compat/linux/linux_syscallargs.h>
64#include <compat/linux/linux_syscall.h>
65#include <compat/linux/common/linux_misc.h>
66#include <compat/linux/common/linux_errno.h>
67#include <compat/linux/common/linux_emuldata.h>
68
69extern struct sysent linux_sysent[];
70extern const char * const linux_syscallnames[];
71extern char linux_sigcode[], linux_esigcode[];
72#ifndef __HAVE_SYSCALL_INTERN
73void syscall __P((void));
74#endif
75
76static void linux_e_proc_exec __P((struct proc *, struct exec_package *));
77static void linux_e_proc_fork __P((struct proc *, struct proc *));
78static void linux_e_proc_exit __P((struct proc *));
79
80/*
81 * Execve(2). Just check the alternate emulation path, and pass it on
82 * to the NetBSD execve().
83 */
84int
85linux_sys_execve(p, v, retval)
86	struct proc *p;
87	void *v;
88	register_t *retval;
89{
90	struct linux_sys_execve_args /* {
91		syscallarg(const char *) path;
92		syscallarg(char **) argv;
93		syscallarg(char **) envp;
94	} */ *uap = v;
95	struct sys_execve_args ap;
96	caddr_t sg;
97
98	sg = stackgap_init(p->p_emul);
99	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
100
101	SCARG(&ap, path) = SCARG(uap, path);
102	SCARG(&ap, argp) = SCARG(uap, argp);
103	SCARG(&ap, envp) = SCARG(uap, envp);
104
105	return sys_execve(p, &ap, retval);
106}
107
108/*
109 * Emulation switch.
110 */
111const struct emul emul_linux = {
112	"linux",
113	"/emul/linux",
114#ifndef __HAVE_MINIMAL_EMUL
115	0,
116	native_to_linux_errno,
117	LINUX_SYS_syscall,
118	LINUX_SYS_MAXSYSCALL,
119#endif
120	linux_sysent,
121	linux_syscallnames,
122	linux_sendsig,
123	linux_sigcode,
124	linux_esigcode,
125	linux_e_proc_exec,
126	linux_e_proc_fork,
127	linux_e_proc_exit,
128#ifdef __HAVE_SYSCALL_INTERN
129	linux_syscall_intern,
130#else
131	syscall,
132#endif
133};
134
135/*
136 * Allocate per-process structures. Called when executing Linux
137 * process. We can re-used the old emuldata - if it's not null,
138 * the executed process is of same emulation as original forked one.
139 */
140static void
141linux_e_proc_exec(p, epp)
142	struct proc *p;
143	struct exec_package *epp;
144{
145	if (!p->p_emuldata) {
146		/* allocate new Linux emuldata */
147		MALLOC(p->p_emuldata, void *, sizeof(struct linux_emuldata),
148			M_EMULDATA, M_WAITOK);
149	}
150
151	memset(p->p_emuldata, '\0', sizeof(struct linux_emuldata));
152}
153
154/*
155 * Emulation per-process exit hook.
156 */
157static void
158linux_e_proc_exit(p)
159	struct proc *p;
160{
161	/* free Linux emuldata and set the pointer to null */
162	FREE(p->p_emuldata, M_EMULDATA);
163	p->p_emuldata = NULL;
164}
165
166/*
167 * Emulation fork hook.
168 */
169static void
170linux_e_proc_fork(p, parent)
171	struct proc *p, *parent;
172{
173	/*
174	 * It could be desirable to copy some stuff from parent's
175	 * emuldata. We don't need anything like that for now.
176	 * So just allocate new emuldata for the new process.
177	 */
178	p->p_emuldata = NULL;
179	linux_e_proc_exec(p, NULL);
180}
181