imgact_svr4.c revision 76166
1/*-
2 * Copyright (c) 1998 Mark Newton
3 * Copyright (c) 1994-1996 S�ren Schmidt
4 * All rights reserved.
5 *
6 * Based heavily on /sys/kern/imgact_aout.c which is:
7 * Copyright (c) 1993, David Greenman
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer
14 *    in this position and unchanged.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 *    derived from this software withough specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 *
32 * $FreeBSD: head/sys/compat/svr4/imgact_svr4.c 76166 2001-05-01 08:13:21Z markm $
33 */
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/exec.h>
38#include <sys/imgact.h>
39#include <sys/imgact_aout.h>
40#include <sys/kernel.h>
41#include <sys/lock.h>
42#include <sys/mman.h>
43#include <sys/mutex.h>
44#include <sys/proc.h>
45#include <sys/resourcevar.h>
46#include <sys/vnode.h>
47
48#include <vm/vm.h>
49#include <vm/vm_kern.h>
50#include <vm/vm_param.h>
51#include <vm/pmap.h>
52#include <vm/vm_map.h>
53#include <vm/vm_extern.h>
54
55#include <compat/svr4/svr4.h>
56
57static int	exec_svr4_imgact __P((struct image_params *iparams));
58
59static int
60exec_svr4_imgact(imgp)
61    struct image_params *imgp;
62{
63    const struct exec *a_out = (const struct exec *) imgp->image_header;
64    struct vmspace *vmspace;
65    vm_offset_t vmaddr;
66    unsigned long virtual_offset, file_offset;
67    vm_offset_t buffer;
68    unsigned long bss_size;
69    int error;
70
71    if (((a_out->a_magic >> 16) & 0xff) != 0x64)
72	return -1;
73
74    /*
75     * Set file/virtual offset based on a.out variant.
76     */
77    switch ((int)(a_out->a_magic & 0xffff)) {
78    case 0413:
79	virtual_offset = 0;
80	file_offset = 1024;
81	break;
82    case 0314:
83	virtual_offset = 4096;
84	file_offset = 0;
85	break;
86    default:
87	return (-1);
88    }
89    bss_size = round_page(a_out->a_bss);
90#ifdef DEBUG
91    printf("imgact: text: %08x, data: %08x, bss: %08x\n", a_out->a_text, a_out->a_data, bss_size);
92#endif
93
94    /*
95     * Check various fields in header for validity/bounds.
96     */
97    if (a_out->a_entry < virtual_offset ||
98	a_out->a_entry >= virtual_offset + a_out->a_text ||
99	a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK)
100	return (-1);
101
102    /* text + data can't exceed file size */
103    if (a_out->a_data + a_out->a_text > imgp->attr->va_size)
104	return (EFAULT);
105    /* For p_rlimit below. */
106    mtx_assert(&Giant, MA_OWNED);
107    /*
108     * text/data/bss must not exceed limits
109     */
110    if (a_out->a_text > MAXTSIZ ||
111	a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur)
112	return (ENOMEM);
113
114    /* copy in arguments and/or environment from old process */
115    error = exec_extract_strings(imgp);
116    if (error)
117	return (error);
118
119    /*
120     * Destroy old process VM and create a new one (with a new stack)
121     */
122    exec_new_vmspace(imgp);
123    vmspace = imgp->proc->p_vmspace;
124
125    /*
126     * Check if file_offset page aligned,.
127     * Currently we cannot handle misalinged file offsets,
128     * and so we read in the entire image (what a waste).
129     */
130    if (file_offset & PAGE_MASK) {
131#ifdef DEBUG
132	printf("imgact: Non page aligned binary %d\n", file_offset);
133#endif
134	/*
135	 * Map text+data+bss read/write/execute
136	 */
137	vmaddr = virtual_offset;
138	error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
139		    	    a_out->a_text + a_out->a_data + bss_size, FALSE,
140			    VM_PROT_ALL, VM_PROT_ALL, 0);
141	if (error)
142	    return error;
143
144	error = vm_mmap(kernel_map, &buffer,
145			round_page(a_out->a_text + a_out->a_data + file_offset),
146			VM_PROT_READ, VM_PROT_READ, 0,
147			(caddr_t) imgp->vp, trunc_page(file_offset));
148	if (error)
149	    return error;
150
151	error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr,
152			a_out->a_text + a_out->a_data);
153
154	vm_map_remove(kernel_map, buffer,
155		      buffer + round_page(a_out->a_text + a_out->a_data + file_offset));
156
157	if (error)
158	    return error;
159
160	/*
161	 * remove write enable on the 'text' part
162	 */
163	error = vm_map_protect(&vmspace->vm_map,
164			       vmaddr,
165		   	       vmaddr + a_out->a_text,
166		   	       VM_PROT_EXECUTE|VM_PROT_READ,
167		   	       TRUE);
168	if (error)
169	    return error;
170    }
171    else {
172#ifdef DEBUG
173	printf("imgact: Page aligned binary %d\n", file_offset);
174#endif
175	/*
176	 * Map text+data read/execute
177	 */
178	vmaddr = virtual_offset;
179	error = vm_mmap(&vmspace->vm_map, &vmaddr,
180			a_out->a_text + a_out->a_data,
181	    		VM_PROT_READ | VM_PROT_EXECUTE,
182	    		VM_PROT_ALL,
183	    		MAP_PRIVATE | MAP_FIXED,
184	    		(caddr_t)imgp->vp, file_offset);
185	if (error)
186	    return (error);
187
188#ifdef DEBUG
189	printf("imgact: startaddr=%08x, length=%08x\n", vmaddr, a_out->a_text + a_out->a_data);
190#endif
191	/*
192	 * allow read/write of data
193	 */
194	error = vm_map_protect(&vmspace->vm_map,
195			       vmaddr + a_out->a_text,
196			       vmaddr + a_out->a_text + a_out->a_data,
197			       VM_PROT_ALL,
198			       FALSE);
199	if (error)
200	    return (error);
201
202	/*
203	 * Allocate anon demand-zeroed area for uninitialized data
204	 */
205	if (bss_size != 0) {
206	    vmaddr = virtual_offset + a_out->a_text + a_out->a_data;
207	    error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
208				bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0);
209	    if (error)
210		return (error);
211#ifdef DEBUG
212	    printf("imgact: bssaddr=%08x, length=%08x\n", vmaddr, bss_size);
213#endif
214
215	}
216	/* Indicate that this file should not be modified */
217	imgp->vp->v_flag |= VTEXT;
218    }
219    /* Fill in process VM information */
220    vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT;
221    vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT;
222    vmspace->vm_taddr = (caddr_t)virtual_offset;
223    vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text;
224
225    /* Fill in image_params */
226    imgp->interpreted = 0;
227    imgp->entry_addr = a_out->a_entry;
228
229    imgp->proc->p_sysent = &svr4_sysvec;
230    return (0);
231}
232
233/*
234 * Tell kern_execve.c about it, with a little help from the linker.
235 */
236struct execsw svr4_execsw = { exec_svr4_imgact, "svr4 ELF" };
237EXEC_SET(execsw_set, svr4_execsw);
238
239