1 /*	$NetBSD: linux_exec_aout.c,v 1.50 2002/10/05 22:34:04 chs 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 1.50 2002/10/05 22:34:04 chs 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/syscallargs.h>
59 
60 #include <machine/cpu.h>
61 #include <machine/reg.h>
62 
63 #include <compat/linux/common/linux_types.h>
64 #include <compat/linux/common/linux_signal.h>
65 #include <compat/linux/common/linux_util.h>
66 #include <compat/linux/common/linux_exec.h>
67 #include <compat/linux/common/linux_machdep.h>
68 
69 #include <compat/linux/linux_syscallargs.h>
70 #include <compat/linux/linux_syscall.h>
71 
72 int linux_aout_copyargs __P((struct proc *, struct exec_package *,
73     struct ps_strings *, char **, void *));
74 
75 static int exec_linux_aout_prep_zmagic __P((struct proc *,
76     struct exec_package *));
77 static int exec_linux_aout_prep_nmagic __P((struct proc *,
78     struct exec_package *));
79 static int exec_linux_aout_prep_omagic __P((struct proc *,
80     struct exec_package *));
81 static int exec_linux_aout_prep_qmagic __P((struct proc *,
82     struct exec_package *));
83 
84 int
85 linux_aout_copyargs(p, pack, arginfo, stackp, argp)
86 	struct proc *p;
87 	struct exec_package *pack;
88 	struct ps_strings *arginfo;
89 	char **stackp;
90 	void *argp;
91 {
92 	char **cpp = (char **)*stackp;
93 	char **stk = (char **)*stackp;
94 	char *dp, *sp;
95 	size_t len;
96 	void *nullp = NULL;
97 	int argc = arginfo->ps_nargvstr;
98 	int envc = arginfo->ps_nenvstr;
99 	int error;
100 
101 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
102 		return error;
103 
104 	/* leave room for envp and argv */
105 	cpp += 2;
106 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
107 		return error;
108 
109 	dp = (char *) (cpp + argc + envc + 2);
110 	sp = argp;
111 
112 	/* XXX don't copy them out, remap them! */
113 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
114 
115 	for (; --argc >= 0; sp += len, dp += len)
116 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
117 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
118 			return error;
119 
120 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
121 		return error;
122 
123 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
124 		return error;
125 
126 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
127 
128 	for (; --envc >= 0; sp += len, dp += len)
129 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
130 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
131 			return error;
132 
133 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
134 		return error;
135 
136 	*stackp = (char *)cpp;
137 	return 0;
138 }
139 
140 int
141 exec_linux_aout_makecmds(p, epp)
142 	struct proc *p;
143 	struct exec_package *epp;
144 {
145 	struct exec *linux_ep = epp->ep_hdr;
146 	int machtype, magic;
147 	int error = ENOEXEC;
148 
149 	magic = LINUX_N_MAGIC(linux_ep);
150 	machtype = LINUX_N_MACHTYPE(linux_ep);
151 
152 
153 	if (machtype != LINUX_MID_MACHINE)
154 		return (ENOEXEC);
155 
156 	switch (magic) {
157 	case QMAGIC:
158 		error = exec_linux_aout_prep_qmagic(p, epp);
159 		break;
160 	case ZMAGIC:
161 		error = exec_linux_aout_prep_zmagic(p, epp);
162 		break;
163 	case NMAGIC:
164 		error = exec_linux_aout_prep_nmagic(p, epp);
165 		break;
166 	case OMAGIC:
167 		error = exec_linux_aout_prep_omagic(p, epp);
168 		break;
169 	}
170 	return error;
171 }
172 
173 /*
174  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
175  * is very likely not page aligned on most architectures, it is treated
176  * as an NMAGIC here. XXX
177  */
178 
179 static int
180 exec_linux_aout_prep_zmagic(p, epp)
181 	struct proc *p;
182 	struct exec_package *epp;
183 {
184 	struct exec *execp = epp->ep_hdr;
185 
186 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
187 	epp->ep_tsize = execp->a_text;
188 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
189 	epp->ep_dsize = execp->a_data + execp->a_bss;
190 	epp->ep_entry = execp->a_entry;
191 
192 	/* set up command for text segment */
193 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
194 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
195 	    VM_PROT_READ|VM_PROT_EXECUTE);
196 
197 	/* set up command for data segment */
198 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
199 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
200 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
201 
202 	/* set up command for bss segment */
203 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
204 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
205 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
206 
207 	return exec_aout_setup_stack(p, epp);
208 }
209 
210 /*
211  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
212  * Not different from the normal stuff.
213  */
214 
215 static int
216 exec_linux_aout_prep_nmagic(p, epp)
217 	struct proc *p;
218 	struct exec_package *epp;
219 {
220 	struct exec *execp = epp->ep_hdr;
221 	long bsize, baddr;
222 
223 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
224 	epp->ep_tsize = execp->a_text;
225 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
226 	epp->ep_dsize = execp->a_data + execp->a_bss;
227 	epp->ep_entry = execp->a_entry;
228 
229 	/* set up command for text segment */
230 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
231 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
232 	    VM_PROT_READ|VM_PROT_EXECUTE);
233 
234 	/* set up command for data segment */
235 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
236 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
237 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
238 
239 	/* set up command for bss segment */
240 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
241 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
242 	if (bsize > 0)
243 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
244 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
245 
246 	return exec_aout_setup_stack(p, epp);
247 }
248 
249 /*
250  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
251  * Business as usual.
252  */
253 
254 static int
255 exec_linux_aout_prep_omagic(p, epp)
256 	struct proc *p;
257 	struct exec_package *epp;
258 {
259 	struct exec *execp = epp->ep_hdr;
260 	long dsize, bsize, baddr;
261 
262 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
263 	epp->ep_tsize = execp->a_text;
264 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
265 	epp->ep_dsize = execp->a_data + execp->a_bss;
266 	epp->ep_entry = execp->a_entry;
267 
268 	/* set up command for text and data segments */
269 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
270 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
271 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
272 
273 	/* set up command for bss segment */
274 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
275 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
276 	if (bsize > 0)
277 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
278 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
279 
280 	/*
281 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
282 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
283 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
284 	 * respectively to page boundaries.
285 	 * Compensate `ep_dsize' for the amount of data covered by the last
286 	 * text page.
287 	 */
288 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
289 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
290 	return exec_aout_setup_stack(p, epp);
291 }
292 
293 static int
294 exec_linux_aout_prep_qmagic(p, epp)
295 	struct proc *p;
296 	struct exec_package *epp;
297 {
298 	struct exec *execp = epp->ep_hdr;
299 	int error;
300 
301 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
302 	epp->ep_tsize = execp->a_text;
303 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
304 	epp->ep_dsize = execp->a_data + execp->a_bss;
305 	epp->ep_entry = execp->a_entry;
306 
307 	error = vn_marktext(epp->ep_vp);
308 	if (error)
309 		return (error);
310 
311 	/* set up command for text segment */
312 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
313 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
314 	    VM_PROT_READ|VM_PROT_EXECUTE);
315 
316 	/* set up command for data segment */
317 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
318 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
319 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
320 
321 	/* set up command for bss segment */
322 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
323 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
324 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
325 
326 	return exec_aout_setup_stack(p, epp);
327 }
328