xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision 17dd36da8292193180754d5047c0926dbb56818c)
1 /*	$NetBSD: linux_exec_aout.c,v 1.44 2000/12/01 13:49:35 jdolecek 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 void *linux_aout_copyargs __P((struct exec_package *,
70     struct ps_strings *, void *, 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 void *
82 linux_aout_copyargs(pack, arginfo, stack, argp)
83 	struct exec_package *pack;
84 	struct ps_strings *arginfo;
85 	void *stack;
86 	void *argp;
87 {
88 	char **cpp = stack;
89 	char **stk = stack;
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 
96 	if (copyout(&argc, cpp++, sizeof(argc)))
97 		return NULL;
98 
99 	/* leave room for envp and argv */
100 	cpp += 2;
101 	if (copyout(&cpp, &stk[1], sizeof (cpp)))
102 		return NULL;
103 
104 	dp = (char *) (cpp + argc + envc + 2);
105 	sp = argp;
106 
107 	/* XXX don't copy them out, remap them! */
108 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
109 
110 	for (; --argc >= 0; sp += len, dp += len)
111 		if (copyout(&dp, cpp++, sizeof(dp)) ||
112 		    copyoutstr(sp, dp, ARG_MAX, &len))
113 			return NULL;
114 
115 	if (copyout(&nullp, cpp++, sizeof(nullp)))
116 		return NULL;
117 
118 	if (copyout(&cpp, &stk[2], sizeof (cpp)))
119 		return NULL;
120 
121 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
122 
123 	for (; --envc >= 0; sp += len, dp += len)
124 		if (copyout(&dp, cpp++, sizeof(dp)) ||
125 		    copyoutstr(sp, dp, ARG_MAX, &len))
126 			return NULL;
127 
128 	if (copyout(&nullp, cpp++, sizeof(nullp)))
129 		return NULL;
130 
131 	return cpp;
132 }
133 
134 int
135 exec_linux_aout_makecmds(p, epp)
136 	struct proc *p;
137 	struct exec_package *epp;
138 {
139 	struct exec *linux_ep = epp->ep_hdr;
140 	int machtype, magic;
141 	int error = ENOEXEC;
142 
143 	magic = LINUX_N_MAGIC(linux_ep);
144 	machtype = LINUX_N_MACHTYPE(linux_ep);
145 
146 
147 	if (machtype != LINUX_MID_MACHINE)
148 		return (ENOEXEC);
149 
150 	switch (magic) {
151 	case QMAGIC:
152 		error = exec_linux_aout_prep_qmagic(p, epp);
153 		break;
154 	case ZMAGIC:
155 		error = exec_linux_aout_prep_zmagic(p, epp);
156 		break;
157 	case NMAGIC:
158 		error = exec_linux_aout_prep_nmagic(p, epp);
159 		break;
160 	case OMAGIC:
161 		error = exec_linux_aout_prep_omagic(p, epp);
162 		break;
163 	}
164 	return error;
165 }
166 
167 /*
168  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
169  * is very likely not page aligned on most architectures, it is treated
170  * as an NMAGIC here. XXX
171  */
172 
173 static int
174 exec_linux_aout_prep_zmagic(p, epp)
175 	struct proc *p;
176 	struct exec_package *epp;
177 {
178 	struct exec *execp = epp->ep_hdr;
179 
180 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
181 	epp->ep_tsize = execp->a_text;
182 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
183 	epp->ep_dsize = execp->a_data + execp->a_bss;
184 	epp->ep_entry = execp->a_entry;
185 
186 	/* set up command for text segment */
187 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
188 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
189 	    VM_PROT_READ|VM_PROT_EXECUTE);
190 
191 	/* set up command for data segment */
192 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
193 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
194 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
195 
196 	/* set up command for bss segment */
197 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
198 	    epp->ep_daddr + execp->a_data, NULLVP, 0,
199 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
200 
201 	return exec_aout_setup_stack(p, epp);
202 }
203 
204 /*
205  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
206  * Not different from the normal stuff.
207  */
208 
209 static int
210 exec_linux_aout_prep_nmagic(p, epp)
211 	struct proc *p;
212 	struct exec_package *epp;
213 {
214 	struct exec *execp = epp->ep_hdr;
215 	long bsize, baddr;
216 
217 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
218 	epp->ep_tsize = execp->a_text;
219 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
220 	epp->ep_dsize = execp->a_data + execp->a_bss;
221 	epp->ep_entry = execp->a_entry;
222 
223 	/* set up command for text segment */
224 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
225 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
226 	    VM_PROT_READ|VM_PROT_EXECUTE);
227 
228 	/* set up command for data segment */
229 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
230 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
231 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
232 
233 	/* set up command for bss segment */
234 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
235 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
236 	if (bsize > 0)
237 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
238 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
239 
240 	return exec_aout_setup_stack(p, epp);
241 }
242 
243 /*
244  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
245  * Business as usual.
246  */
247 
248 static int
249 exec_linux_aout_prep_omagic(p, epp)
250 	struct proc *p;
251 	struct exec_package *epp;
252 {
253 	struct exec *execp = epp->ep_hdr;
254 	long dsize, bsize, baddr;
255 
256 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
257 	epp->ep_tsize = execp->a_text;
258 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
259 	epp->ep_dsize = execp->a_data + execp->a_bss;
260 	epp->ep_entry = execp->a_entry;
261 
262 	/* set up command for text and data segments */
263 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
264 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
265 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
266 
267 	/* set up command for bss segment */
268 	baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
269 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
270 	if (bsize > 0)
271 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
272 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
273 
274 	/*
275 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
276 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
277 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
278 	 * respectively to page boundaries.
279 	 * Compensate `ep_dsize' for the amount of data covered by the last
280 	 * text page.
281 	 */
282 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
283 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
284 	return exec_aout_setup_stack(p, epp);
285 }
286 
287 static int
288 exec_linux_aout_prep_qmagic(p, epp)
289 	struct proc *p;
290 	struct exec_package *epp;
291 {
292 	struct exec *execp = epp->ep_hdr;
293 
294 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
295 	epp->ep_tsize = execp->a_text;
296 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
297 	epp->ep_dsize = execp->a_data + execp->a_bss;
298 	epp->ep_entry = execp->a_entry;
299 
300 	/*
301 	 * check if vnode is in open for writing, because we want to
302 	 * demand-page out of it.  if it is, don't do it, for various
303 	 * reasons
304 	 */
305 	if ((execp->a_text != 0 || execp->a_data != 0) &&
306 	    epp->ep_vp->v_writecount != 0) {
307 #ifdef DIAGNOSTIC
308 		if (epp->ep_vp->v_flag & VTEXT)
309 			panic("exec: a VTEXT vnode has writecount != 0\n");
310 #endif
311 		return ETXTBSY;
312 	}
313 	vn_marktext(epp->ep_vp);
314 
315 	/* set up command for text segment */
316 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
317 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
318 	    VM_PROT_READ|VM_PROT_EXECUTE);
319 
320 	/* set up command for data segment */
321 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
322 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
323 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
324 
325 	/* set up command for bss segment */
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 exec_aout_setup_stack(p, epp);
331 }
332