xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision b5cd2489b2952ee409ede7b61183dba7ab0359ad)
1 /*	$NetBSD: linux_exec_aout.c,v 1.46 2001/10/30 15:32:02 thorpej 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/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/proc.h>
47 #include <sys/malloc.h>
48 #include <sys/namei.h>
49 #include <sys/vnode.h>
50 #include <sys/mount.h>
51 #include <sys/exec.h>
52 #include <sys/exec_elf.h>
53 
54 #include <sys/mman.h>
55 #include <sys/syscallargs.h>
56 
57 #include <machine/cpu.h>
58 #include <machine/reg.h>
59 
60 #include <compat/linux/common/linux_types.h>
61 #include <compat/linux/common/linux_signal.h>
62 #include <compat/linux/common/linux_util.h>
63 #include <compat/linux/common/linux_exec.h>
64 #include <compat/linux/common/linux_machdep.h>
65 
66 #include <compat/linux/linux_syscallargs.h>
67 #include <compat/linux/linux_syscall.h>
68 
69 int linux_aout_copyargs __P((struct exec_package *, struct ps_strings *,
70     char **, void *));
71 
72 static int exec_linux_aout_prep_zmagic __P((struct proc *,
73     struct exec_package *));
74 static int exec_linux_aout_prep_nmagic __P((struct proc *,
75     struct exec_package *));
76 static int exec_linux_aout_prep_omagic __P((struct proc *,
77     struct exec_package *));
78 static int exec_linux_aout_prep_qmagic __P((struct proc *,
79     struct exec_package *));
80 
81 int
82 linux_aout_copyargs(pack, arginfo, stackp, argp)
83 	struct exec_package *pack;
84 	struct ps_strings *arginfo;
85 	char **stackp;
86 	void *argp;
87 {
88 	char **cpp = (char **)*stackp;
89 	char **stk = (char **)*stackp;
90 	char *dp, *sp;
91 	size_t len;
92 	void *nullp = NULL;
93 	int argc = arginfo->ps_nargvstr;
94 	int envc = arginfo->ps_nenvstr;
95 	int error;
96 
97 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
98 		return error;
99 
100 	/* leave room for envp and argv */
101 	cpp += 2;
102 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
103 		return error;
104 
105 	dp = (char *) (cpp + argc + envc + 2);
106 	sp = argp;
107 
108 	/* XXX don't copy them out, remap them! */
109 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
110 
111 	for (; --argc >= 0; sp += len, dp += len)
112 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
113 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
114 			return error;
115 
116 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
117 		return error;
118 
119 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
120 		return error;
121 
122 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
123 
124 	for (; --envc >= 0; sp += len, dp += len)
125 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
126 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
127 			return error;
128 
129 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
130 		return error;
131 
132 	*stackp = (char *)cpp;
133 	return 0;
134 }
135 
136 int
137 exec_linux_aout_makecmds(p, epp)
138 	struct proc *p;
139 	struct exec_package *epp;
140 {
141 	struct exec *linux_ep = epp->ep_hdr;
142 	int machtype, magic;
143 	int error = ENOEXEC;
144 
145 	magic = LINUX_N_MAGIC(linux_ep);
146 	machtype = LINUX_N_MACHTYPE(linux_ep);
147 
148 
149 	if (machtype != LINUX_MID_MACHINE)
150 		return (ENOEXEC);
151 
152 	switch (magic) {
153 	case QMAGIC:
154 		error = exec_linux_aout_prep_qmagic(p, epp);
155 		break;
156 	case ZMAGIC:
157 		error = exec_linux_aout_prep_zmagic(p, epp);
158 		break;
159 	case NMAGIC:
160 		error = exec_linux_aout_prep_nmagic(p, epp);
161 		break;
162 	case OMAGIC:
163 		error = exec_linux_aout_prep_omagic(p, epp);
164 		break;
165 	}
166 	return error;
167 }
168 
169 /*
170  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
171  * is very likely not page aligned on most architectures, it is treated
172  * as an NMAGIC here. XXX
173  */
174 
175 static int
176 exec_linux_aout_prep_zmagic(p, epp)
177 	struct proc *p;
178 	struct exec_package *epp;
179 {
180 	struct exec *execp = epp->ep_hdr;
181 
182 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
183 	epp->ep_tsize = execp->a_text;
184 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
185 	epp->ep_dsize = execp->a_data + execp->a_bss;
186 	epp->ep_entry = execp->a_entry;
187 
188 	/* set up command for text segment */
189 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
190 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
191 	    VM_PROT_READ|VM_PROT_EXECUTE);
192 
193 	/* set up command for data segment */
194 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
195 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
196 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
197 
198 	/* set up command for bss segment */
199 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
200 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
201 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
202 
203 	return exec_aout_setup_stack(p, epp);
204 }
205 
206 /*
207  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
208  * Not different from the normal stuff.
209  */
210 
211 static int
212 exec_linux_aout_prep_nmagic(p, epp)
213 	struct proc *p;
214 	struct exec_package *epp;
215 {
216 	struct exec *execp = epp->ep_hdr;
217 	long bsize, baddr;
218 
219 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
220 	epp->ep_tsize = execp->a_text;
221 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
222 	epp->ep_dsize = execp->a_data + execp->a_bss;
223 	epp->ep_entry = execp->a_entry;
224 
225 	/* set up command for text segment */
226 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
227 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
228 	    VM_PROT_READ|VM_PROT_EXECUTE);
229 
230 	/* set up command for data segment */
231 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
232 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
233 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
234 
235 	/* set up command for bss segment */
236 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
237 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
238 	if (bsize > 0)
239 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
240 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
241 
242 	return exec_aout_setup_stack(p, epp);
243 }
244 
245 /*
246  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
247  * Business as usual.
248  */
249 
250 static int
251 exec_linux_aout_prep_omagic(p, epp)
252 	struct proc *p;
253 	struct exec_package *epp;
254 {
255 	struct exec *execp = epp->ep_hdr;
256 	long dsize, bsize, baddr;
257 
258 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
259 	epp->ep_tsize = execp->a_text;
260 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
261 	epp->ep_dsize = execp->a_data + execp->a_bss;
262 	epp->ep_entry = execp->a_entry;
263 
264 	/* set up command for text and data segments */
265 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
266 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
267 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
268 
269 	/* set up command for bss segment */
270 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
271 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
272 	if (bsize > 0)
273 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
274 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
275 
276 	/*
277 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
278 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
279 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
280 	 * respectively to page boundaries.
281 	 * Compensate `ep_dsize' for the amount of data covered by the last
282 	 * text page.
283 	 */
284 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
285 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
286 	return exec_aout_setup_stack(p, epp);
287 }
288 
289 static int
290 exec_linux_aout_prep_qmagic(p, epp)
291 	struct proc *p;
292 	struct exec_package *epp;
293 {
294 	struct exec *execp = epp->ep_hdr;
295 
296 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
297 	epp->ep_tsize = execp->a_text;
298 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
299 	epp->ep_dsize = execp->a_data + execp->a_bss;
300 	epp->ep_entry = execp->a_entry;
301 
302 	/*
303 	 * check if vnode is in open for writing, because we want to
304 	 * demand-page out of it.  if it is, don't do it, for various
305 	 * reasons
306 	 */
307 	if ((execp->a_text != 0 || execp->a_data != 0) &&
308 	    epp->ep_vp->v_writecount != 0) {
309 #ifdef DIAGNOSTIC
310 		if (epp->ep_vp->v_flag & VTEXT)
311 			panic("exec: a VTEXT vnode has writecount != 0\n");
312 #endif
313 		return ETXTBSY;
314 	}
315 	epp->ep_vp->v_flag |= VTEXT;
316 
317 	/* set up command for text segment */
318 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
319 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
320 	    VM_PROT_READ|VM_PROT_EXECUTE);
321 
322 	/* set up command for data segment */
323 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
324 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
325 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
326 
327 	/* set up command for bss segment */
328 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
329 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
330 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
331 
332 	return exec_aout_setup_stack(p, epp);
333 }
334