linux_exec_aout.c revision 1.3 1 /* $NetBSD: linux_exec_aout.c,v 1.3 1995/04/07 22:23:22 fvdl Exp $ */
2
3 /*
4 * Copyright (c) 1995 Frank van der Linden
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed for the NetBSD Project
18 * by Frank van der Linden
19 * 4. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 * based on kern/exec_aout.c and compat/sunos/sunos_exec.c
34 */
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/filedesc.h>
39 #include <sys/kernel.h>
40 #include <sys/proc.h>
41 #include <sys/mount.h>
42 #include <sys/malloc.h>
43 #include <sys/namei.h>
44 #include <sys/vnode.h>
45 #include <sys/file.h>
46 #include <sys/resourcevar.h>
47 #include <sys/wait.h>
48
49 #include <sys/mman.h>
50 #include <vm/vm.h>
51 #include <vm/vm_param.h>
52 #include <vm/vm_map.h>
53 #include <vm/vm_kern.h>
54 #include <vm/vm_pager.h>
55
56 #include <machine/cpu.h>
57 #include <machine/reg.h>
58 #include <machine/exec.h>
59
60 #include <compat/linux/linux_types.h>
61 #include <compat/linux/linux_syscallargs.h>
62 #include <compat/linux/linux_util.h>
63 #include <compat/linux/linux_exec.h>
64
65 int
66 exec_linux_aout_makecmds(p, epp)
67 struct proc *p;
68 struct exec_package *epp;
69 {
70 struct exec *linux_ep = epp->ep_hdr;
71 int machtype, magic;
72 int error = ENOEXEC;
73
74 magic = LINUX_N_MAGIC(linux_ep);
75 machtype = LINUX_N_MACHTYPE(linux_ep);
76
77
78 if (machtype != LINUX_MID_MACHINE)
79 return (ENOEXEC);
80
81 switch (magic) {
82 case QMAGIC:
83 error = exec_linux_aout_prep_qmagic(p, epp);
84 break;
85 case ZMAGIC:
86 error = exec_linux_aout_prep_zmagic(p, epp);
87 break;
88 case NMAGIC:
89 error = exec_linux_aout_prep_nmagic(p, epp);
90 break;
91 case OMAGIC:
92 error = exec_linux_aout_prep_omagic(p, epp);
93 break;
94 }
95 if (error == 0) {
96 epp->ep_sigcode = linux_sigcode;
97 epp->ep_esigcode = linux_esigcode;
98 epp->ep_emul = EMUL_LINUX;
99 }
100 return error;
101 }
102
103 /*
104 * Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
105 * is very likely not page aligned on most architectures, it is treated
106 * as an NMAGIC here. XXX
107 */
108
109 int
110 exec_linux_aout_prep_zmagic(p, epp)
111 struct proc *p;
112 struct exec_package *epp;
113 {
114 struct exec *execp = epp->ep_hdr;
115
116 epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
117 epp->ep_tsize = execp->a_text;
118 epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
119 epp->ep_dsize = execp->a_data + execp->a_bss;
120 epp->ep_entry = execp->a_entry;
121
122 /* set up command for text segment */
123 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
124 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
125 VM_PROT_READ|VM_PROT_EXECUTE);
126
127 /* set up command for data segment */
128 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
129 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
130 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
131
132 /* set up command for bss segment */
133 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
134 epp->ep_daddr + execp->a_data, NULLVP, 0,
135 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
136
137 return exec_aout_setup_stack(p, epp);
138 }
139
140 /*
141 * exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
142 * Not different from the normal stuff.
143 */
144
145 int
146 exec_linux_aout_prep_nmagic(p, epp)
147 struct proc *p;
148 struct exec_package *epp;
149 {
150 struct exec *execp = epp->ep_hdr;
151 long bsize, baddr;
152
153 epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
154 epp->ep_tsize = execp->a_text;
155 epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
156 epp->ep_dsize = execp->a_data + execp->a_bss;
157 epp->ep_entry = execp->a_entry;
158
159 /* set up command for text segment */
160 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
161 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
162 VM_PROT_READ|VM_PROT_EXECUTE);
163
164 /* set up command for data segment */
165 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
166 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
167 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
168
169 /* set up command for bss segment */
170 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
171 bsize = epp->ep_daddr + epp->ep_dsize - baddr;
172 if (bsize > 0)
173 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
174 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
175
176 return exec_aout_setup_stack(p, epp);
177 }
178
179 /*
180 * exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
181 * Business as usual.
182 */
183
184 int
185 exec_linux_aout_prep_omagic(p, epp)
186 struct proc *p;
187 struct exec_package *epp;
188 {
189 struct exec *execp = epp->ep_hdr;
190 long dsize, bsize, baddr;
191
192 epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
193 epp->ep_tsize = execp->a_text;
194 epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
195 epp->ep_dsize = execp->a_data + execp->a_bss;
196 epp->ep_entry = execp->a_entry;
197
198 /* set up command for text and data segments */
199 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
200 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
201 LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
202
203 /* set up command for bss segment */
204 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
205 bsize = epp->ep_daddr + epp->ep_dsize - baddr;
206 if (bsize > 0)
207 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
208 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
209
210 /*
211 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
212 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
213 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
214 * respectively to page boundaries.
215 * Compensate `ep_dsize' for the amount of data covered by the last
216 * text page.
217 */
218 dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
219 epp->ep_dsize = (dsize > 0) ? dsize : 0;
220 return exec_aout_setup_stack(p, epp);
221 }
222
223 int
224 exec_linux_aout_prep_qmagic(p, epp)
225 struct proc *p;
226 struct exec_package *epp;
227 {
228 struct exec *execp = epp->ep_hdr;
229
230 epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
231 epp->ep_tsize = execp->a_text;
232 epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
233 epp->ep_dsize = execp->a_data + execp->a_bss;
234 epp->ep_entry = execp->a_entry;
235
236 /*
237 * check if vnode is in open for writing, because we want to
238 * demand-page out of it. if it is, don't do it, for various
239 * reasons
240 */
241 if ((execp->a_text != 0 || execp->a_data != 0) &&
242 epp->ep_vp->v_writecount != 0) {
243 #ifdef DIAGNOSTIC
244 if (epp->ep_vp->v_flag & VTEXT)
245 panic("exec: a VTEXT vnode has writecount != 0\n");
246 #endif
247 return ETXTBSY;
248 }
249 epp->ep_vp->v_flag |= VTEXT;
250
251 /* set up command for text segment */
252 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
253 epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
254 VM_PROT_READ|VM_PROT_EXECUTE);
255
256 /* set up command for data segment */
257 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
258 epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
259 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
260
261 /* set up command for bss segment */
262 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
263 epp->ep_daddr + execp->a_data, NULLVP, 0,
264 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
265
266 return exec_aout_setup_stack(p, epp);
267 }
268
269 /*
270 * The Linux system call to load shared libraries. The current shared
271 * libraries are just (QMAGIC) a.out files that are mapped onto a fixed
272 * address * in the process' address space. The address is given in
273 * a_entry. Read in the header, set up some VM commands and run them.
274 *
275 * Yes, both text and data are mapped at once, so we're left with
276 * writeable text for the shared libs. The Linux crt0 seemed to break
277 * sometimes when data was mapped seperately. It munmapped a uselib()
278 * of ld.so by hand, which failed with shared text and data for ld.so
279 * Yuck.
280 *
281 * Because of the problem with ZMAGIC executables (text starts
282 * at 0x400 in the file, but needs t be mapped at 0), ZMAGIC
283 * shared libs are not handled very efficiently :-(
284 */
285
286 int
287 linux_uselib(p, uap, retval)
288 struct proc *p;
289 struct linux_uselib_args /* {
290 syscallarg(char *) path;
291 } */ *uap;
292 register_t *retval;
293 {
294 caddr_t sg;
295 long bsize, dsize, tsize, taddr, baddr, daddr;
296 struct nameidata ni;
297 struct vnode *vp;
298 struct exec hdr;
299 struct exec_vmcmd_set vcset;
300 int rem, i, magic, error;
301
302 sg = stackgap_init();
303 CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
304
305 NDINIT(&ni, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
306
307 if ((error = namei(&ni)))
308 return error;
309
310 vp = ni.ni_vp;
311
312 if ((error = vn_rdwr(UIO_READ, vp, (caddr_t) &hdr, LINUX_AOUT_HDR_SIZE,
313 0, UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
314 &rem, p))) {
315 vrele(vp);
316 return error;
317 }
318
319 if (rem != 0) {
320 vrele(vp);
321 return ENOEXEC;
322 }
323
324 magic = LINUX_N_MAGIC(&hdr);
325 taddr = hdr.a_entry & (~(NBPG - 1));
326 tsize = hdr.a_text;
327 daddr = taddr + tsize;
328 dsize = hdr.a_data + hdr.a_bss;
329
330 if ((hdr.a_text != 0 || hdr.a_data != 0) && vp->v_writecount != 0) {
331 vrele(vp);
332 return ETXTBSY;
333 }
334 vp->v_flag |= VTEXT;
335
336 vcset.evs_cnt = 0;
337 vcset.evs_used = 0;
338
339 NEW_VMCMD(&vcset,
340 magic == ZMAGIC ? vmcmd_map_readvn : vmcmd_map_pagedvn,
341 hdr.a_text + hdr.a_data, taddr,
342 vp, LINUX_N_TXTOFF(hdr, magic),
343 VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE);
344
345 baddr = roundup(daddr + hdr.a_data, NBPG);
346 bsize = daddr + dsize - baddr;
347 if (bsize > 0) {
348 NEW_VMCMD(&vcset, vmcmd_map_zero, bsize, baddr,
349 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
350 }
351
352 for (i = 0; i < vcset.evs_used && !error; i++) {
353 struct exec_vmcmd *vcp;
354
355 vcp = &vcset.evs_cmds[i];
356 error = (*vcp->ev_proc)(p, vcp);
357 }
358
359 kill_vmcmds(&vcset);
360
361 vrele(vp);
362
363 return error;
364 }
365
366 /*
367 * Execve(2). Just check the alternate emulation path, and pass it on
368 * to the NetBSD execve().
369 */
370 int
371 linux_execve(p, uap, retval)
372 struct proc *p;
373 struct linux_execve_args /* {
374 syscallarg(char *) path;
375 syscallarg(char **) argv;
376 syscallarg(char **) envp;
377 } */ *uap;
378 register_t *retval;
379 {
380 caddr_t sg;
381
382 sg = stackgap_init();
383 CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
384
385 return execve(p, uap, retval);
386 }
387