1 /* $NetBSD: linux_exec_aout.c,v 1.68 2015/10/18 16:59:19 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 1.68 2015/10/18 16:59:19 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
linux_aout_copyargs(struct lwp * l,struct exec_package * pack,struct ps_strings * arginfo,char ** stackp,void * argp)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
exec_linux_aout_makecmds(struct lwp * l,struct exec_package * epp)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 if (epp->ep_hdrvalid < sizeof(struct exec))
139 return ENOEXEC;
140
141 magic = LINUX_N_MAGIC(linux_ep);
142 machtype = LINUX_N_MACHTYPE(linux_ep);
143
144 if (machtype != LINUX_MID_MACHINE)
145 return (ENOEXEC);
146
147 switch (magic) {
148 case QMAGIC:
149 error = exec_linux_aout_prep_qmagic(l, epp);
150 break;
151 case ZMAGIC:
152 error = exec_linux_aout_prep_zmagic(l, epp);
153 break;
154 case NMAGIC:
155 error = exec_linux_aout_prep_nmagic(l, epp);
156 break;
157 case OMAGIC:
158 error = exec_linux_aout_prep_omagic(l, epp);
159 break;
160 }
161 return error;
162 }
163
164 /*
165 * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
166 * is very likely not page aligned on most architectures, it is treated
167 * as an NMAGIC here. XXX
168 */
169
170 static int
exec_linux_aout_prep_zmagic(struct lwp * l,struct exec_package * epp)171 exec_linux_aout_prep_zmagic(struct lwp *l, struct exec_package *epp)
172 {
173 struct exec *execp = epp->ep_hdr;
174
175 epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
176 epp->ep_tsize = execp->a_text;
177 epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
178 epp->ep_dsize = execp->a_data + execp->a_bss;
179 epp->ep_entry = execp->a_entry;
180
181 /* set up command for text segment */
182 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
183 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
184 VM_PROT_READ|VM_PROT_EXECUTE);
185
186 /* set up command for data segment */
187 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
188 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
189 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
190
191 /* set up command for bss segment */
192 if (execp->a_bss)
193 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
194 epp->ep_daddr + execp->a_data, NULLVP, 0,
195 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
196
197 return (*epp->ep_esch->es_setup_stack)(l, epp);
198 }
199
200 /*
201 * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
202 * Not different from the normal stuff.
203 */
204
205 static int
exec_linux_aout_prep_nmagic(struct lwp * l,struct exec_package * epp)206 exec_linux_aout_prep_nmagic(struct lwp *l, struct exec_package *epp)
207 {
208 struct exec *execp = epp->ep_hdr;
209 long bsize, baddr;
210
211 epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
212 epp->ep_tsize = execp->a_text;
213 epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
214 epp->ep_dsize = execp->a_data + execp->a_bss;
215 epp->ep_entry = execp->a_entry;
216
217 /* set up command for text segment */
218 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
219 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
220 VM_PROT_READ|VM_PROT_EXECUTE);
221
222 /* set up command for data segment */
223 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
224 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
225 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
226
227 /* set up command for bss segment */
228 baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
229 bsize = epp->ep_daddr + epp->ep_dsize - baddr;
230 if (bsize > 0)
231 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
232 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
233
234 return (*epp->ep_esch->es_setup_stack)(l, epp);
235 }
236
237 /*
238 * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
239 * Business as usual.
240 */
241
242 static int
exec_linux_aout_prep_omagic(struct lwp * l,struct exec_package * epp)243 exec_linux_aout_prep_omagic(struct lwp *l, struct exec_package *epp)
244 {
245 struct exec *execp = epp->ep_hdr;
246 long dsize, bsize, baddr;
247
248 epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
249 epp->ep_tsize = execp->a_text;
250 epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
251 epp->ep_dsize = execp->a_data + execp->a_bss;
252 epp->ep_entry = execp->a_entry;
253
254 /* set up command for text and data segments */
255 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
256 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
257 LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
258
259 /* set up command for bss segment */
260 baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
261 bsize = epp->ep_daddr + epp->ep_dsize - baddr;
262 if (bsize > 0)
263 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
264 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
265
266 /*
267 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
268 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
269 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
270 * respectively to page boundaries.
271 * Compensate `ep_dsize' for the amount of data covered by the last
272 * text page.
273 */
274 dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
275 PAGE_SIZE);
276 epp->ep_dsize = (dsize > 0) ? dsize : 0;
277 return (*epp->ep_esch->es_setup_stack)(l, epp);
278 }
279
280 static int
exec_linux_aout_prep_qmagic(struct lwp * l,struct exec_package * epp)281 exec_linux_aout_prep_qmagic(struct lwp *l, struct exec_package *epp)
282 {
283 struct exec *execp = epp->ep_hdr;
284 int error;
285
286 epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
287 epp->ep_tsize = execp->a_text;
288 epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
289 epp->ep_dsize = execp->a_data + execp->a_bss;
290 epp->ep_entry = execp->a_entry;
291
292 error = vn_marktext(epp->ep_vp);
293 if (error)
294 return (error);
295
296 /* set up command for text segment */
297 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
298 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
299 VM_PROT_READ|VM_PROT_EXECUTE);
300
301 /* set up command for data segment */
302 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
303 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
304 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
305
306 /* set up command for bss segment */
307 if (execp->a_bss)
308 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
309 epp->ep_daddr + execp->a_data, NULLVP, 0,
310 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
311
312 return (*epp->ep_esch->es_setup_stack)(l, epp);
313 }
314