1 /*	$NetBSD: linux_exec_aout.c,v 1.57 2005/02/26 23:10:19 perry Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998 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 and Eric Haszlakiewicz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * based on exec_aout.c, sunos_exec.c and svr4_exec.c
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: linux_exec_aout.c,v 1.57 2005/02/26 23:10:19 perry Exp $");
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/proc.h>
50 #include <sys/malloc.h>
51 #include <sys/namei.h>
52 #include <sys/vnode.h>
53 #include <sys/mount.h>
54 #include <sys/exec.h>
55 #include <sys/exec_elf.h>
56 
57 #include <sys/mman.h>
58 #include <sys/sa.h>
59 #include <sys/syscallargs.h>
60 
61 #include <machine/cpu.h>
62 #include <machine/reg.h>
63 
64 #include <compat/linux/common/linux_types.h>
65 #include <compat/linux/common/linux_signal.h>
66 #include <compat/linux/common/linux_util.h>
67 #include <compat/linux/common/linux_exec.h>
68 #include <compat/linux/common/linux_machdep.h>
69 
70 #include <compat/linux/linux_syscallargs.h>
71 #include <compat/linux/linux_syscall.h>
72 
73 int linux_aout_copyargs __P((struct proc *, struct exec_package *,
74     struct ps_strings *, char **, void *));
75 
76 static int exec_linux_aout_prep_zmagic __P((struct proc *,
77     struct exec_package *));
78 static int exec_linux_aout_prep_nmagic __P((struct proc *,
79     struct exec_package *));
80 static int exec_linux_aout_prep_omagic __P((struct proc *,
81     struct exec_package *));
82 static int exec_linux_aout_prep_qmagic __P((struct proc *,
83     struct exec_package *));
84 
85 int
86 linux_aout_copyargs(p, pack, arginfo, stackp, argp)
87 	struct proc *p;
88 	struct exec_package *pack;
89 	struct ps_strings *arginfo;
90 	char **stackp;
91 	void *argp;
92 {
93 	char **cpp = (char **)*stackp;
94 	char **stk = (char **)*stackp;
95 	char *dp, *sp;
96 	size_t len;
97 	void *nullp = NULL;
98 	int argc = arginfo->ps_nargvstr;
99 	int envc = arginfo->ps_nenvstr;
100 	int error;
101 
102 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
103 		return error;
104 
105 	/* leave room for envp and argv */
106 	cpp += 2;
107 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
108 		return error;
109 
110 	dp = (char *) (cpp + argc + envc + 2);
111 	sp = argp;
112 
113 	/* XXX don't copy them out, remap them! */
114 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
115 
116 	for (; --argc >= 0; sp += len, dp += len)
117 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
118 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
119 			return error;
120 
121 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
122 		return error;
123 
124 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
125 		return error;
126 
127 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
128 
129 	for (; --envc >= 0; sp += len, dp += len)
130 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
131 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
132 			return error;
133 
134 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
135 		return error;
136 
137 	*stackp = (char *)cpp;
138 	return 0;
139 }
140 
141 int
142 exec_linux_aout_makecmds(p, epp)
143 	struct proc *p;
144 	struct exec_package *epp;
145 {
146 	struct exec *linux_ep = epp->ep_hdr;
147 	int machtype, magic;
148 	int error = ENOEXEC;
149 
150 	magic = LINUX_N_MAGIC(linux_ep);
151 	machtype = LINUX_N_MACHTYPE(linux_ep);
152 
153 
154 	if (machtype != LINUX_MID_MACHINE)
155 		return (ENOEXEC);
156 
157 	switch (magic) {
158 	case QMAGIC:
159 		error = exec_linux_aout_prep_qmagic(p, epp);
160 		break;
161 	case ZMAGIC:
162 		error = exec_linux_aout_prep_zmagic(p, epp);
163 		break;
164 	case NMAGIC:
165 		error = exec_linux_aout_prep_nmagic(p, epp);
166 		break;
167 	case OMAGIC:
168 		error = exec_linux_aout_prep_omagic(p, epp);
169 		break;
170 	}
171 	return error;
172 }
173 
174 /*
175  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
176  * is very likely not page aligned on most architectures, it is treated
177  * as an NMAGIC here. XXX
178  */
179 
180 static int
181 exec_linux_aout_prep_zmagic(p, epp)
182 	struct proc *p;
183 	struct exec_package *epp;
184 {
185 	struct exec *execp = epp->ep_hdr;
186 
187 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
188 	epp->ep_tsize = execp->a_text;
189 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
190 	epp->ep_dsize = execp->a_data + execp->a_bss;
191 	epp->ep_entry = execp->a_entry;
192 
193 	/* set up command for text segment */
194 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
195 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
196 	    VM_PROT_READ|VM_PROT_EXECUTE);
197 
198 	/* set up command for data segment */
199 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
200 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
201 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
202 
203 	/* set up command for bss segment */
204 	if (execp->a_bss)
205 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
206 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
207 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
208 
209 	return (*epp->ep_esch->es_setup_stack)(p, epp);
210 }
211 
212 /*
213  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
214  * Not different from the normal stuff.
215  */
216 
217 static int
218 exec_linux_aout_prep_nmagic(p, epp)
219 	struct proc *p;
220 	struct exec_package *epp;
221 {
222 	struct exec *execp = epp->ep_hdr;
223 	long bsize, baddr;
224 
225 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
226 	epp->ep_tsize = execp->a_text;
227 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
228 	epp->ep_dsize = execp->a_data + execp->a_bss;
229 	epp->ep_entry = execp->a_entry;
230 
231 	/* set up command for text segment */
232 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
233 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
234 	    VM_PROT_READ|VM_PROT_EXECUTE);
235 
236 	/* set up command for data segment */
237 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
238 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
239 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
240 
241 	/* set up command for bss segment */
242 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
243 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
244 	if (bsize > 0)
245 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
246 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
247 
248 	return (*epp->ep_esch->es_setup_stack)(p, epp);
249 }
250 
251 /*
252  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
253  * Business as usual.
254  */
255 
256 static int
257 exec_linux_aout_prep_omagic(p, epp)
258 	struct proc *p;
259 	struct exec_package *epp;
260 {
261 	struct exec *execp = epp->ep_hdr;
262 	long dsize, bsize, baddr;
263 
264 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
265 	epp->ep_tsize = execp->a_text;
266 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
267 	epp->ep_dsize = execp->a_data + execp->a_bss;
268 	epp->ep_entry = execp->a_entry;
269 
270 	/* set up command for text and data segments */
271 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
272 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
273 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
274 
275 	/* set up command for bss segment */
276 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
277 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
278 	if (bsize > 0)
279 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
280 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
281 
282 	/*
283 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
284 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
285 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
286 	 * respectively to page boundaries.
287 	 * Compensate `ep_dsize' for the amount of data covered by the last
288 	 * text page.
289 	 */
290 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
291 							PAGE_SIZE);
292 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
293 	return (*epp->ep_esch->es_setup_stack)(p, epp);
294 }
295 
296 static int
297 exec_linux_aout_prep_qmagic(p, epp)
298 	struct proc *p;
299 	struct exec_package *epp;
300 {
301 	struct exec *execp = epp->ep_hdr;
302 	int error;
303 
304 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
305 	epp->ep_tsize = execp->a_text;
306 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
307 	epp->ep_dsize = execp->a_data + execp->a_bss;
308 	epp->ep_entry = execp->a_entry;
309 
310 	error = vn_marktext(epp->ep_vp);
311 	if (error)
312 		return (error);
313 
314 	/* set up command for text segment */
315 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
316 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
317 	    VM_PROT_READ|VM_PROT_EXECUTE);
318 
319 	/* set up command for data segment */
320 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
321 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
322 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
323 
324 	/* set up command for bss segment */
325 	if (execp->a_bss)
326 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
327 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
328 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
329 
330 	return (*epp->ep_esch->es_setup_stack)(p, epp);
331 }
332