xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision 271138cb3a6de667c600b54c1d0896e7b41a929b)
1 /*	$NetBSD: linux_exec_aout.c,v 1.66 2009/08/15 23:39:35 matt 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 1.66 2009/08/15 23:39:35 matt Exp $");
38 
39 #ifdef _KERNEL_OPT
40 #include "opt_execfmt.h"
41 #endif
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 
53 #include <sys/mman.h>
54 #include <sys/syscallargs.h>
55 
56 #include <sys/cpu.h>
57 #include <machine/reg.h>
58 
59 #include <compat/linux/common/linux_types.h>
60 #include <compat/linux/common/linux_signal.h>
61 #include <compat/linux/common/linux_util.h>
62 #include <compat/linux/common/linux_exec.h>
63 #include <compat/linux/common/linux_machdep.h>
64 
65 #include <compat/linux/linux_syscallargs.h>
66 #include <compat/linux/linux_syscall.h>
67 
68 int linux_aout_copyargs(struct lwp *, struct exec_package *,
69     struct ps_strings *, char **, void *);
70 
71 static int exec_linux_aout_prep_zmagic(struct lwp *,
72     struct exec_package *);
73 static int exec_linux_aout_prep_nmagic(struct lwp *,
74     struct exec_package *);
75 static int exec_linux_aout_prep_omagic(struct lwp *,
76     struct exec_package *);
77 static int exec_linux_aout_prep_qmagic(struct lwp *,
78     struct exec_package *);
79 
80 int
81 linux_aout_copyargs(struct lwp *l, struct exec_package *pack,
82     struct ps_strings *arginfo, char **stackp, void *argp)
83 {
84 	char **cpp = (char **)*stackp;
85 	char **stk = (char **)*stackp;
86 	char *dp, *sp;
87 	size_t len;
88 	void *nullp = NULL;
89 	int argc = arginfo->ps_nargvstr;
90 	int envc = arginfo->ps_nenvstr;
91 	int error;
92 
93 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
94 		return error;
95 
96 	/* leave room for envp and argv */
97 	cpp += 2;
98 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
99 		return error;
100 
101 	dp = (char *) (cpp + argc + envc + 2);
102 	sp = argp;
103 
104 	/* XXX don't copy them out, remap them! */
105 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
106 
107 	for (; --argc >= 0; sp += len, dp += len)
108 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
109 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
110 			return error;
111 
112 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
113 		return error;
114 
115 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
116 		return error;
117 
118 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
119 
120 	for (; --envc >= 0; sp += len, dp += len)
121 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
122 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
123 			return error;
124 
125 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
126 		return error;
127 
128 	*stackp = (char *)cpp;
129 	return 0;
130 }
131 
132 int
133 exec_linux_aout_makecmds(struct lwp *l, struct exec_package *epp)
134 {
135 	struct exec *linux_ep = epp->ep_hdr;
136 	int machtype, magic;
137 	int error = ENOEXEC;
138 
139 	magic = LINUX_N_MAGIC(linux_ep);
140 	machtype = LINUX_N_MACHTYPE(linux_ep);
141 
142 
143 	if (machtype != LINUX_MID_MACHINE)
144 		return (ENOEXEC);
145 
146 	switch (magic) {
147 	case QMAGIC:
148 		error = exec_linux_aout_prep_qmagic(l, epp);
149 		break;
150 	case ZMAGIC:
151 		error = exec_linux_aout_prep_zmagic(l, epp);
152 		break;
153 	case NMAGIC:
154 		error = exec_linux_aout_prep_nmagic(l, epp);
155 		break;
156 	case OMAGIC:
157 		error = exec_linux_aout_prep_omagic(l, epp);
158 		break;
159 	}
160 	return error;
161 }
162 
163 /*
164  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
165  * is very likely not page aligned on most architectures, it is treated
166  * as an NMAGIC here. XXX
167  */
168 
169 static int
170 exec_linux_aout_prep_zmagic(struct lwp *l, struct exec_package *epp)
171 {
172 	struct exec *execp = epp->ep_hdr;
173 
174 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
175 	epp->ep_tsize = execp->a_text;
176 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
177 	epp->ep_dsize = execp->a_data + execp->a_bss;
178 	epp->ep_entry = execp->a_entry;
179 
180 	/* set up command for text segment */
181 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
182 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
183 	    VM_PROT_READ|VM_PROT_EXECUTE);
184 
185 	/* set up command for data segment */
186 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
187 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
188 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
189 
190 	/* set up command for bss segment */
191 	if (execp->a_bss)
192 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
193 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
194 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
195 
196 	return (*epp->ep_esch->es_setup_stack)(l, epp);
197 }
198 
199 /*
200  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
201  * Not different from the normal stuff.
202  */
203 
204 static int
205 exec_linux_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
206 {
207 	struct exec *execp = epp->ep_hdr;
208 	long bsize, baddr;
209 
210 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
211 	epp->ep_tsize = execp->a_text;
212 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
213 	epp->ep_dsize = execp->a_data + execp->a_bss;
214 	epp->ep_entry = execp->a_entry;
215 
216 	/* set up command for text segment */
217 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
218 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
219 	    VM_PROT_READ|VM_PROT_EXECUTE);
220 
221 	/* set up command for data segment */
222 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
223 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
224 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
225 
226 	/* set up command for bss segment */
227 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
228 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
229 	if (bsize > 0)
230 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
231 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
232 
233 	return (*epp->ep_esch->es_setup_stack)(l, epp);
234 }
235 
236 /*
237  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
238  * Business as usual.
239  */
240 
241 static int
242 exec_linux_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
243 {
244 	struct exec *execp = epp->ep_hdr;
245 	long dsize, bsize, baddr;
246 
247 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
248 	epp->ep_tsize = execp->a_text;
249 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
250 	epp->ep_dsize = execp->a_data + execp->a_bss;
251 	epp->ep_entry = execp->a_entry;
252 
253 	/* set up command for text and data segments */
254 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
255 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
256 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
257 
258 	/* set up command for bss segment */
259 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
260 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
261 	if (bsize > 0)
262 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
263 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
264 
265 	/*
266 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
267 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
268 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
269 	 * respectively to page boundaries.
270 	 * Compensate `ep_dsize' for the amount of data covered by the last
271 	 * text page.
272 	 */
273 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
274 							PAGE_SIZE);
275 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
276 	return (*epp->ep_esch->es_setup_stack)(l, epp);
277 }
278 
279 static int
280 exec_linux_aout_prep_qmagic(struct lwp *l, struct exec_package *epp)
281 {
282 	struct exec *execp = epp->ep_hdr;
283 	int error;
284 
285 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
286 	epp->ep_tsize = execp->a_text;
287 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
288 	epp->ep_dsize = execp->a_data + execp->a_bss;
289 	epp->ep_entry = execp->a_entry;
290 
291 	error = vn_marktext(epp->ep_vp);
292 	if (error)
293 		return (error);
294 
295 	/* set up command for text segment */
296 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
297 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
298 	    VM_PROT_READ|VM_PROT_EXECUTE);
299 
300 	/* set up command for data segment */
301 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
302 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
303 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
304 
305 	/* set up command for bss segment */
306 	if (execp->a_bss)
307 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
308 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
309 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
310 
311 	return (*epp->ep_esch->es_setup_stack)(l, epp);
312 }
313