xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision 74809f044aa1c34df701bf79c7bfb9794896fdf8)
1 /*	$NetBSD: linux_exec_aout.c,v 1.65 2008/04/28 20:23:43 martin 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * based on exec_aout.c, sunos_exec.c and svr4_exec.c
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: linux_exec_aout.c,v 1.65 2008/04/28 20:23:43 martin Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/proc.h>
43 #include <sys/malloc.h>
44 #include <sys/namei.h>
45 #include <sys/vnode.h>
46 #include <sys/mount.h>
47 #include <sys/exec.h>
48 #include <sys/exec_elf.h>
49 
50 #include <sys/mman.h>
51 #include <sys/syscallargs.h>
52 
53 #include <sys/cpu.h>
54 #include <machine/reg.h>
55 
56 #include <compat/linux/common/linux_types.h>
57 #include <compat/linux/common/linux_signal.h>
58 #include <compat/linux/common/linux_util.h>
59 #include <compat/linux/common/linux_exec.h>
60 #include <compat/linux/common/linux_machdep.h>
61 
62 #include <compat/linux/linux_syscallargs.h>
63 #include <compat/linux/linux_syscall.h>
64 
65 int linux_aout_copyargs(struct lwp *, struct exec_package *,
66     struct ps_strings *, char **, void *);
67 
68 static int exec_linux_aout_prep_zmagic(struct lwp *,
69     struct exec_package *);
70 static int exec_linux_aout_prep_nmagic(struct lwp *,
71     struct exec_package *);
72 static int exec_linux_aout_prep_omagic(struct lwp *,
73     struct exec_package *);
74 static int exec_linux_aout_prep_qmagic(struct lwp *,
75     struct exec_package *);
76 
77 int
78 linux_aout_copyargs(struct lwp *l, struct exec_package *pack,
79     struct ps_strings *arginfo, char **stackp, void *argp)
80 {
81 	char **cpp = (char **)*stackp;
82 	char **stk = (char **)*stackp;
83 	char *dp, *sp;
84 	size_t len;
85 	void *nullp = NULL;
86 	int argc = arginfo->ps_nargvstr;
87 	int envc = arginfo->ps_nenvstr;
88 	int error;
89 
90 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
91 		return error;
92 
93 	/* leave room for envp and argv */
94 	cpp += 2;
95 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
96 		return error;
97 
98 	dp = (char *) (cpp + argc + envc + 2);
99 	sp = argp;
100 
101 	/* XXX don't copy them out, remap them! */
102 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
103 
104 	for (; --argc >= 0; sp += len, dp += len)
105 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
106 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
107 			return error;
108 
109 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
110 		return error;
111 
112 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
113 		return error;
114 
115 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
116 
117 	for (; --envc >= 0; sp += len, dp += len)
118 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
119 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
120 			return error;
121 
122 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
123 		return error;
124 
125 	*stackp = (char *)cpp;
126 	return 0;
127 }
128 
129 int
130 exec_linux_aout_makecmds(struct lwp *l, struct exec_package *epp)
131 {
132 	struct exec *linux_ep = epp->ep_hdr;
133 	int machtype, magic;
134 	int error = ENOEXEC;
135 
136 	magic = LINUX_N_MAGIC(linux_ep);
137 	machtype = LINUX_N_MACHTYPE(linux_ep);
138 
139 
140 	if (machtype != LINUX_MID_MACHINE)
141 		return (ENOEXEC);
142 
143 	switch (magic) {
144 	case QMAGIC:
145 		error = exec_linux_aout_prep_qmagic(l, epp);
146 		break;
147 	case ZMAGIC:
148 		error = exec_linux_aout_prep_zmagic(l, epp);
149 		break;
150 	case NMAGIC:
151 		error = exec_linux_aout_prep_nmagic(l, epp);
152 		break;
153 	case OMAGIC:
154 		error = exec_linux_aout_prep_omagic(l, epp);
155 		break;
156 	}
157 	return error;
158 }
159 
160 /*
161  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
162  * is very likely not page aligned on most architectures, it is treated
163  * as an NMAGIC here. XXX
164  */
165 
166 static int
167 exec_linux_aout_prep_zmagic(struct lwp *l, struct exec_package *epp)
168 {
169 	struct exec *execp = epp->ep_hdr;
170 
171 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
172 	epp->ep_tsize = execp->a_text;
173 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
174 	epp->ep_dsize = execp->a_data + execp->a_bss;
175 	epp->ep_entry = execp->a_entry;
176 
177 	/* set up command for text segment */
178 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
179 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
180 	    VM_PROT_READ|VM_PROT_EXECUTE);
181 
182 	/* set up command for data segment */
183 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
184 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
185 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
186 
187 	/* set up command for bss segment */
188 	if (execp->a_bss)
189 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
190 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
191 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
192 
193 	return (*epp->ep_esch->es_setup_stack)(l, epp);
194 }
195 
196 /*
197  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
198  * Not different from the normal stuff.
199  */
200 
201 static int
202 exec_linux_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
203 {
204 	struct exec *execp = epp->ep_hdr;
205 	long bsize, baddr;
206 
207 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
208 	epp->ep_tsize = execp->a_text;
209 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
210 	epp->ep_dsize = execp->a_data + execp->a_bss;
211 	epp->ep_entry = execp->a_entry;
212 
213 	/* set up command for text segment */
214 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
215 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
216 	    VM_PROT_READ|VM_PROT_EXECUTE);
217 
218 	/* set up command for data segment */
219 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
220 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
221 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
222 
223 	/* set up command for bss segment */
224 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
225 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
226 	if (bsize > 0)
227 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
228 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
229 
230 	return (*epp->ep_esch->es_setup_stack)(l, epp);
231 }
232 
233 /*
234  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
235  * Business as usual.
236  */
237 
238 static int
239 exec_linux_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
240 {
241 	struct exec *execp = epp->ep_hdr;
242 	long dsize, bsize, baddr;
243 
244 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
245 	epp->ep_tsize = execp->a_text;
246 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
247 	epp->ep_dsize = execp->a_data + execp->a_bss;
248 	epp->ep_entry = execp->a_entry;
249 
250 	/* set up command for text and data segments */
251 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
252 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
253 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
254 
255 	/* set up command for bss segment */
256 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
257 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
258 	if (bsize > 0)
259 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
260 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
261 
262 	/*
263 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
264 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
265 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
266 	 * respectively to page boundaries.
267 	 * Compensate `ep_dsize' for the amount of data covered by the last
268 	 * text page.
269 	 */
270 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
271 							PAGE_SIZE);
272 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
273 	return (*epp->ep_esch->es_setup_stack)(l, epp);
274 }
275 
276 static int
277 exec_linux_aout_prep_qmagic(struct lwp *l, struct exec_package *epp)
278 {
279 	struct exec *execp = epp->ep_hdr;
280 	int error;
281 
282 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
283 	epp->ep_tsize = execp->a_text;
284 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
285 	epp->ep_dsize = execp->a_data + execp->a_bss;
286 	epp->ep_entry = execp->a_entry;
287 
288 	error = vn_marktext(epp->ep_vp);
289 	if (error)
290 		return (error);
291 
292 	/* set up command for text segment */
293 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
294 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
295 	    VM_PROT_READ|VM_PROT_EXECUTE);
296 
297 	/* set up command for data segment */
298 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
299 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
300 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
301 
302 	/* set up command for bss segment */
303 	if (execp->a_bss)
304 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
305 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
306 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
307 
308 	return (*epp->ep_esch->es_setup_stack)(l, epp);
309 }
310