xref: /netbsd-src/sys/compat/linux/common/linux_exec_aout.c (revision aad9773e38ed2370a628a6416e098f9008fc10a7)
1 /*	$NetBSD: linux_exec_aout.c,v 1.67 2014/11/09 17:48:08 maxv 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 1.67 2014/11/09 17:48:08 maxv 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/namei.h>
48 #include <sys/vnode.h>
49 #include <sys/mount.h>
50 #include <sys/exec.h>
51 
52 #include <sys/mman.h>
53 #include <sys/syscallargs.h>
54 
55 #include <sys/cpu.h>
56 #include <machine/reg.h>
57 
58 #include <compat/linux/common/linux_types.h>
59 #include <compat/linux/common/linux_signal.h>
60 #include <compat/linux/common/linux_util.h>
61 #include <compat/linux/common/linux_exec.h>
62 #include <compat/linux/common/linux_machdep.h>
63 
64 #include <compat/linux/linux_syscallargs.h>
65 #include <compat/linux/linux_syscall.h>
66 
67 int linux_aout_copyargs(struct lwp *, struct exec_package *,
68     struct ps_strings *, char **, void *);
69 
70 static int exec_linux_aout_prep_zmagic(struct lwp *,
71     struct exec_package *);
72 static int exec_linux_aout_prep_nmagic(struct lwp *,
73     struct exec_package *);
74 static int exec_linux_aout_prep_omagic(struct lwp *,
75     struct exec_package *);
76 static int exec_linux_aout_prep_qmagic(struct lwp *,
77     struct exec_package *);
78 
79 int
80 linux_aout_copyargs(struct lwp *l, struct exec_package *pack,
81     struct ps_strings *arginfo, char **stackp, void *argp)
82 {
83 	char **cpp = (char **)*stackp;
84 	char **stk = (char **)*stackp;
85 	char *dp, *sp;
86 	size_t len;
87 	void *nullp = NULL;
88 	int argc = arginfo->ps_nargvstr;
89 	int envc = arginfo->ps_nenvstr;
90 	int error;
91 
92 	if ((error = copyout(&argc, cpp++, sizeof(argc))) != 0)
93 		return error;
94 
95 	/* leave room for envp and argv */
96 	cpp += 2;
97 	if ((error = copyout(&cpp, &stk[1], sizeof (cpp))) != 0)
98 		return error;
99 
100 	dp = (char *) (cpp + argc + envc + 2);
101 	sp = argp;
102 
103 	/* XXX don't copy them out, remap them! */
104 	arginfo->ps_argvstr = cpp; /* remember location of argv for later */
105 
106 	for (; --argc >= 0; sp += len, dp += len)
107 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
108 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
109 			return error;
110 
111 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
112 		return error;
113 
114 	if ((error = copyout(&cpp, &stk[2], sizeof (cpp))) != 0)
115 		return error;
116 
117 	arginfo->ps_envstr = cpp; /* remember location of envp for later */
118 
119 	for (; --envc >= 0; sp += len, dp += len)
120 		if ((error = copyout(&dp, cpp++, sizeof(dp))) != 0 ||
121 		    (error = copyoutstr(sp, dp, ARG_MAX, &len)) != 0)
122 			return error;
123 
124 	if ((error = copyout(&nullp, cpp++, sizeof(nullp))) != 0)
125 		return error;
126 
127 	*stackp = (char *)cpp;
128 	return 0;
129 }
130 
131 int
132 exec_linux_aout_makecmds(struct lwp *l, struct exec_package *epp)
133 {
134 	struct exec *linux_ep = epp->ep_hdr;
135 	int machtype, magic;
136 	int error = ENOEXEC;
137 
138 	magic = LINUX_N_MAGIC(linux_ep);
139 	machtype = LINUX_N_MACHTYPE(linux_ep);
140 
141 
142 	if (machtype != LINUX_MID_MACHINE)
143 		return (ENOEXEC);
144 
145 	switch (magic) {
146 	case QMAGIC:
147 		error = exec_linux_aout_prep_qmagic(l, epp);
148 		break;
149 	case ZMAGIC:
150 		error = exec_linux_aout_prep_zmagic(l, epp);
151 		break;
152 	case NMAGIC:
153 		error = exec_linux_aout_prep_nmagic(l, epp);
154 		break;
155 	case OMAGIC:
156 		error = exec_linux_aout_prep_omagic(l, epp);
157 		break;
158 	}
159 	return error;
160 }
161 
162 /*
163  * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
164  * is very likely not page aligned on most architectures, it is treated
165  * as an NMAGIC here. XXX
166  */
167 
168 static int
169 exec_linux_aout_prep_zmagic(struct lwp *l, struct exec_package *epp)
170 {
171 	struct exec *execp = epp->ep_hdr;
172 
173 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
174 	epp->ep_tsize = execp->a_text;
175 	epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
176 	epp->ep_dsize = execp->a_data + execp->a_bss;
177 	epp->ep_entry = execp->a_entry;
178 
179 	/* set up command for text segment */
180 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
181 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
182 	    VM_PROT_READ|VM_PROT_EXECUTE);
183 
184 	/* set up command for data segment */
185 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
186 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
187 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
188 
189 	/* set up command for bss segment */
190 	if (execp->a_bss)
191 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
192 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
193 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
194 
195 	return (*epp->ep_esch->es_setup_stack)(l, epp);
196 }
197 
198 /*
199  * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
200  * Not different from the normal stuff.
201  */
202 
203 static int
204 exec_linux_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
205 {
206 	struct exec *execp = epp->ep_hdr;
207 	long bsize, baddr;
208 
209 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
210 	epp->ep_tsize = execp->a_text;
211 	epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
212 	epp->ep_dsize = execp->a_data + execp->a_bss;
213 	epp->ep_entry = execp->a_entry;
214 
215 	/* set up command for text segment */
216 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
217 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
218 	    VM_PROT_READ|VM_PROT_EXECUTE);
219 
220 	/* set up command for data segment */
221 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
222 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
223 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
224 
225 	/* set up command for bss segment */
226 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
227 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
228 	if (bsize > 0)
229 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
230 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
231 
232 	return (*epp->ep_esch->es_setup_stack)(l, epp);
233 }
234 
235 /*
236  * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
237  * Business as usual.
238  */
239 
240 static int
241 exec_linux_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
242 {
243 	struct exec *execp = epp->ep_hdr;
244 	long dsize, bsize, baddr;
245 
246 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
247 	epp->ep_tsize = execp->a_text;
248 	epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
249 	epp->ep_dsize = execp->a_data + execp->a_bss;
250 	epp->ep_entry = execp->a_entry;
251 
252 	/* set up command for text and data segments */
253 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
254 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
255 	    LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
256 
257 	/* set up command for bss segment */
258 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
259 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
260 	if (bsize > 0)
261 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
262 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
263 
264 	/*
265 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
266 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
267 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
268 	 * respectively to page boundaries.
269 	 * Compensate `ep_dsize' for the amount of data covered by the last
270 	 * text page.
271 	 */
272 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
273 							PAGE_SIZE);
274 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
275 	return (*epp->ep_esch->es_setup_stack)(l, epp);
276 }
277 
278 static int
279 exec_linux_aout_prep_qmagic(struct lwp *l, struct exec_package *epp)
280 {
281 	struct exec *execp = epp->ep_hdr;
282 	int error;
283 
284 	epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
285 	epp->ep_tsize = execp->a_text;
286 	epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
287 	epp->ep_dsize = execp->a_data + execp->a_bss;
288 	epp->ep_entry = execp->a_entry;
289 
290 	error = vn_marktext(epp->ep_vp);
291 	if (error)
292 		return (error);
293 
294 	/* set up command for text segment */
295 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
296 	    epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
297 	    VM_PROT_READ|VM_PROT_EXECUTE);
298 
299 	/* set up command for data segment */
300 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
301 	    epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
302 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
303 
304 	/* set up command for bss segment */
305 	if (execp->a_bss)
306 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
307 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
308 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
309 
310 	return (*epp->ep_esch->es_setup_stack)(l, epp);
311 }
312