xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: linux_exec_aout.c,v 1.64 2007/12/08 18:36:07 dsl 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 1.64 2007/12/08 18:36:07 dsl 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 <sys/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(struct lwp *, struct exec_package *,
73     struct ps_strings *, char **, void *);
74 
75 static int exec_linux_aout_prep_zmagic(struct lwp *,
76     struct exec_package *);
77 static int exec_linux_aout_prep_nmagic(struct lwp *,
78     struct exec_package *);
79 static int exec_linux_aout_prep_omagic(struct lwp *,
80     struct exec_package *);
81 static int exec_linux_aout_prep_qmagic(struct lwp *,
82     struct exec_package *);
83 
84 int
85 linux_aout_copyargs(struct lwp *l, struct exec_package *pack,
86     struct ps_strings *arginfo, char **stackp, 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(struct lwp *l, 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(l, epp);
153 		break;
154 	case ZMAGIC:
155 		error = exec_linux_aout_prep_zmagic(l, epp);
156 		break;
157 	case NMAGIC:
158 		error = exec_linux_aout_prep_nmagic(l, epp);
159 		break;
160 	case OMAGIC:
161 		error = exec_linux_aout_prep_omagic(l, 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(struct lwp *l, struct exec_package *epp)
175 {
176 	struct exec *execp = epp->ep_hdr;
177 
178 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
179 	epp->ep_tsize = execp->a_text;
180 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
181 	epp->ep_dsize = execp->a_data + execp->a_bss;
182 	epp->ep_entry = execp->a_entry;
183 
184 	/* set up command for text segment */
185 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
186 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
187 	    VM_PROT_READ|VM_PROT_EXECUTE);
188 
189 	/* set up command for data segment */
190 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
191 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
192 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
193 
194 	/* set up command for bss segment */
195 	if (execp->a_bss)
196 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
197 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
198 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
199 
200 	return (*epp->ep_esch->es_setup_stack)(l, epp);
201 }
202 
203 /*
204  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
205  * Not different from the normal stuff.
206  */
207 
208 static int
209 exec_linux_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
210 {
211 	struct exec *execp = epp->ep_hdr;
212 	long bsize, baddr;
213 
214 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
215 	epp->ep_tsize = execp->a_text;
216 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
217 	epp->ep_dsize = execp->a_data + execp->a_bss;
218 	epp->ep_entry = execp->a_entry;
219 
220 	/* set up command for text segment */
221 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
222 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
223 	    VM_PROT_READ|VM_PROT_EXECUTE);
224 
225 	/* set up command for data segment */
226 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
227 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
228 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
229 
230 	/* set up command for bss segment */
231 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
232 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
233 	if (bsize > 0)
234 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
235 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
236 
237 	return (*epp->ep_esch->es_setup_stack)(l, epp);
238 }
239 
240 /*
241  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
242  * Business as usual.
243  */
244 
245 static int
246 exec_linux_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
247 {
248 	struct exec *execp = epp->ep_hdr;
249 	long dsize, bsize, baddr;
250 
251 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
252 	epp->ep_tsize = execp->a_text;
253 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
254 	epp->ep_dsize = execp->a_data + execp->a_bss;
255 	epp->ep_entry = execp->a_entry;
256 
257 	/* set up command for text and data segments */
258 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
259 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
260 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
261 
262 	/* set up command for bss segment */
263 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
264 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
265 	if (bsize > 0)
266 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
267 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
268 
269 	/*
270 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
271 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
272 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
273 	 * respectively to page boundaries.
274 	 * Compensate `ep_dsize' for the amount of data covered by the last
275 	 * text page.
276 	 */
277 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
278 							PAGE_SIZE);
279 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
280 	return (*epp->ep_esch->es_setup_stack)(l, epp);
281 }
282 
283 static int
284 exec_linux_aout_prep_qmagic(struct lwp *l, struct exec_package *epp)
285 {
286 	struct exec *execp = epp->ep_hdr;
287 	int error;
288 
289 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
290 	epp->ep_tsize = execp->a_text;
291 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
292 	epp->ep_dsize = execp->a_data + execp->a_bss;
293 	epp->ep_entry = execp->a_entry;
294 
295 	error = vn_marktext(epp->ep_vp);
296 	if (error)
297 		return (error);
298 
299 	/* set up command for text segment */
300 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
301 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
302 	    VM_PROT_READ|VM_PROT_EXECUTE);
303 
304 	/* set up command for data segment */
305 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
306 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
307 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
308 
309 	/* set up command for bss segment */
310 	if (execp->a_bss)
311 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
312 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
313 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
314 
315 	return (*epp->ep_esch->es_setup_stack)(l, epp);
316 }
317