1 /*-
2 * Copyright (c) 1994-1996 Søren Schmidt
3 * All rights reserved.
4 *
5 * Based heavily on /sys/kern/imgact_aout.c which is:
6 * Copyright (c) 1993, David Greenman
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer
13 * in this position and unchanged.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 * derived from this software without specific prior written permission
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: releng/9.2/sys/i386/linux/imgact_linux.c 232387 2012-03-02 11:32:47Z kib $");
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/racct.h>
46 #include <sys/resourcevar.h>
47 #include <sys/vnode.h>
48
49 #include <vm/vm.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_param.h>
52 #include <vm/pmap.h>
53 #include <vm/vm_map.h>
54 #include <vm/vm_extern.h>
55
56 #include <i386/linux/linux.h>
57
58 static int exec_linux_imgact(struct image_params *iparams);
59
60 static int
61 exec_linux_imgact(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 unsigned long bss_size;
68 ssize_t aresid;
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: %08lx, data: %08lx, bss: %08lx\n",
92 (u_long)a_out->a_text, (u_long)a_out->a_data, bss_size);
93 #endif
94
95 /*
96 * Check various fields in header for validity/bounds.
97 */
98 if (a_out->a_entry < virtual_offset ||
99 a_out->a_entry >= virtual_offset + a_out->a_text ||
100 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK)
101 return (-1);
102
103 /* text + data can't exceed file size */
104 if (a_out->a_data + a_out->a_text > imgp->attr->va_size)
105 return (EFAULT);
106 /*
107 * text/data/bss must not exceed limits
108 */
109 PROC_LOCK(imgp->proc);
110 if (a_out->a_text > maxtsiz ||
111 a_out->a_data + bss_size > lim_cur(imgp->proc, RLIMIT_DATA) ||
112 racct_set(imgp->proc, RACCT_DATA, a_out->a_data + bss_size) != 0) {
113 PROC_UNLOCK(imgp->proc);
114 return (ENOMEM);
115 }
116 PROC_UNLOCK(imgp->proc);
117
118 VOP_UNLOCK(imgp->vp, 0);
119
120 /*
121 * Destroy old process VM and create a new one (with a new stack)
122 */
123 error = exec_new_vmspace(imgp, &linux_sysvec);
124 if (error)
125 goto fail;
126 vmspace = imgp->proc->p_vmspace;
127
128 /*
129 * Check if file_offset page aligned,.
130 * Currently we cannot handle misaligned file offsets,
131 * and so we read in the entire image (what a waste).
132 */
133 if (file_offset & PAGE_MASK) {
134 #ifdef DEBUG
135 printf("imgact: Non page aligned binary %lu\n", file_offset);
136 #endif
137 /*
138 * Map text+data+bss read/write/execute
139 */
140 vmaddr = virtual_offset;
141 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
142 a_out->a_text + a_out->a_data + bss_size, FALSE,
143 VM_PROT_ALL, VM_PROT_ALL, 0);
144 if (error)
145 goto fail;
146
147 error = vn_rdwr(UIO_READ, imgp->vp, (void *)vmaddr, file_offset,
148 a_out->a_text + a_out->a_data, UIO_USERSPACE, 0,
149 curthread->td_ucred, NOCRED, &aresid, curthread);
150 if (error != 0)
151 goto fail;
152 if (aresid != 0) {
153 error = ENOEXEC;
154 goto fail;
155 }
156
157 /*
158 * remove write enable on the 'text' part
159 */
160 error = vm_map_protect(&vmspace->vm_map,
161 vmaddr,
162 vmaddr + a_out->a_text,
163 VM_PROT_EXECUTE|VM_PROT_READ,
164 TRUE);
165 if (error)
166 goto fail;
167 }
168 else {
169 #ifdef DEBUG
170 printf("imgact: Page aligned binary %lu\n", file_offset);
171 #endif
172 /*
173 * Map text+data read/execute
174 */
175 vmaddr = virtual_offset;
176 error = vm_mmap(&vmspace->vm_map, &vmaddr,
177 a_out->a_text + a_out->a_data,
178 VM_PROT_READ | VM_PROT_EXECUTE,
179 VM_PROT_ALL,
180 MAP_PRIVATE | MAP_FIXED,
181 OBJT_VNODE,
182 imgp->vp, file_offset);
183 if (error)
184 goto fail;
185
186 #ifdef DEBUG
187 printf("imgact: startaddr=%08lx, length=%08lx\n",
188 (u_long)vmaddr, (u_long)a_out->a_text + (u_long)a_out->a_data);
189 #endif
190 /*
191 * allow read/write of data
192 */
193 error = vm_map_protect(&vmspace->vm_map,
194 vmaddr + a_out->a_text,
195 vmaddr + a_out->a_text + a_out->a_data,
196 VM_PROT_ALL,
197 FALSE);
198 if (error)
199 goto fail;
200
201 /*
202 * Allocate anon demand-zeroed area for uninitialized data
203 */
204 if (bss_size != 0) {
205 vmaddr = virtual_offset + a_out->a_text + a_out->a_data;
206 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
207 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0);
208 if (error)
209 goto fail;
210 #ifdef DEBUG
211 printf("imgact: bssaddr=%08lx, length=%08lx\n",
212 (u_long)vmaddr, bss_size);
213 #endif
214
215 }
216 }
217 /* Fill in process VM information */
218 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT;
219 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT;
220 vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset;
221 vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t)
222 (virtual_offset + a_out->a_text);
223
224 /* Fill in image_params */
225 imgp->interpreted = 0;
226 imgp->entry_addr = a_out->a_entry;
227
228 imgp->proc->p_sysent = &linux_sysvec;
229
230 fail:
231 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
232 return (error);
233 }
234
235 /*
236 * Tell kern_execve.c about it, with a little help from the linker.
237 */
238 static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" };
239 EXEC_SET(linuxaout, linux_execsw);
Cache object: 825aa027764bec8b5f7ba4a43a9d2c61
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