netbsd32_execve.c revision 1.9.2.1 1 /* $NetBSD: netbsd32_execve.c,v 1.9.2.1 2002/06/20 16:41:09 gehenna Exp $ */
2
3 /*
4 * Copyright (c) 1998, 2001 Matthew R. Green
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. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: netbsd32_execve.c,v 1.9.2.1 2002/06/20 16:41:09 gehenna Exp $");
33
34 #if defined(_KERNEL_OPT)
35 #include "opt_ktrace.h"
36 #endif
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/mount.h>
42 #include <sys/stat.h>
43 #include <sys/wait.h>
44 #include <sys/ktrace.h>
45 #include <sys/vnode.h>
46 #include <sys/file.h>
47 #include <sys/filedesc.h>
48 #include <sys/namei.h>
49
50 #include <uvm/uvm_extern.h>
51
52 #include <sys/syscallargs.h>
53 #include <sys/proc.h>
54 #include <sys/acct.h>
55 #include <sys/exec.h>
56
57 #include <compat/netbsd32/netbsd32.h>
58 #include <compat/netbsd32/netbsd32_syscall.h>
59 #include <compat/netbsd32/netbsd32_syscallargs.h>
60
61 /* this is provided by kern/kern_exec.c */
62 extern int exec_maxhdrsz;
63 #if defined(LKM) || defined(_LKM)
64 extern struct lock exec_lock;
65 #endif
66
67 /*
68 * Need to completly reimplement this syscall due to argument copying.
69 */
70 /* ARGSUSED */
71 int
72 netbsd32_execve(p, v, retval)
73 struct proc *p;
74 void *v;
75 register_t *retval;
76 {
77 struct netbsd32_execve_args /* {
78 syscallarg(const netbsd32_charp) path;
79 syscallarg(netbsd32_charpp) argp;
80 syscallarg(netbsd32_charpp) envp;
81 } */ *uap = v;
82 struct sys_execve_args ua;
83 caddr_t sg;
84
85 NETBSD32TOP_UAP(path, const char);
86 NETBSD32TOP_UAP(argp, char *);
87 NETBSD32TOP_UAP(envp, char *);
88 sg = stackgap_init(p, 0);
89 CHECK_ALT_EXIST(p, &sg, SCARG(&ua, path));
90
91 return netbsd32_execve2(p, &ua, retval);
92 }
93
94 int
95 netbsd32_execve2(p, uap, retval)
96 struct proc *p;
97 struct sys_execve_args *uap;
98 register_t *retval;
99 {
100 /* Function args */
101 int error, i;
102 struct exec_package pack;
103 struct nameidata nid;
104 struct vattr attr;
105 struct ucred *cred = p->p_ucred;
106 char *argp;
107 netbsd32_charp const *cpp;
108 char *dp;
109 netbsd32_charp sp;
110 long argc, envc;
111 size_t len;
112 char *stack;
113 struct ps_strings arginfo;
114 struct vmspace *vm;
115 char **tmpfap;
116 int szsigcode;
117 struct exec_vmcmd *base_vcp = NULL;
118
119 /*
120 * Init the namei data to point the file user's program name.
121 * This is done here rather than in check_exec(), so that it's
122 * possible to override this settings if any of makecmd/probe
123 * functions call check_exec() recursively - for example,
124 * see exec_script_makecmds().
125 */
126 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
127
128 /*
129 * initialize the fields of the exec package.
130 */
131 pack.ep_name = SCARG(uap, path);
132 pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK);
133 pack.ep_hdrlen = exec_maxhdrsz;
134 pack.ep_hdrvalid = 0;
135 pack.ep_ndp = &nid;
136 pack.ep_emul_arg = NULL;
137 pack.ep_vmcmds.evs_cnt = 0;
138 pack.ep_vmcmds.evs_used = 0;
139 pack.ep_vap = &attr;
140 pack.ep_flags = 0;
141
142 #if defined(LKM) || defined(_LKM)
143 lockmgr(&exec_lock, LK_SHARED, NULL);
144 #endif
145
146 /* see if we can run it. */
147 if ((error = check_exec(p, &pack)) != 0)
148 goto freehdr;
149
150 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */
151
152 /* allocate an argument buffer */
153 argp = (char *) uvm_km_valloc_wait(exec_map, NCARGS);
154 #ifdef DIAGNOSTIC
155 if (argp == (vaddr_t) 0)
156 panic("netbsd32_execve: argp == NULL");
157 #endif
158 dp = argp;
159 argc = 0;
160
161 /* copy the fake args list, if there's one, freeing it as we go */
162 if (pack.ep_flags & EXEC_HASARGL) {
163 tmpfap = pack.ep_fa;
164 while (*tmpfap != NULL) {
165 char *cp;
166
167 cp = *tmpfap;
168 while (*cp)
169 *dp++ = *cp++;
170 dp++;
171
172 FREE(*tmpfap, M_EXEC);
173 tmpfap++; argc++;
174 }
175 FREE(pack.ep_fa, M_EXEC);
176 pack.ep_flags &= ~EXEC_HASARGL;
177 }
178
179 /* Now get argv & environment */
180 if (!(cpp = (netbsd32_charp *)SCARG(uap, argp))) {
181 error = EINVAL;
182 goto bad;
183 }
184
185 if (pack.ep_flags & EXEC_SKIPARG)
186 cpp++;
187
188 while (1) {
189 len = argp + ARG_MAX - dp;
190 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0)
191 goto bad;
192 if (!sp)
193 break;
194 if ((error = copyinstr((char *)(u_long)sp, dp,
195 len, &len)) != 0) {
196 if (error == ENAMETOOLONG)
197 error = E2BIG;
198 goto bad;
199 }
200 dp += len;
201 cpp++;
202 argc++;
203 }
204
205 envc = 0;
206 /* environment need not be there */
207 if ((cpp = (netbsd32_charp *)SCARG(uap, envp)) != NULL ) {
208 while (1) {
209 len = argp + ARG_MAX - dp;
210 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0)
211 goto bad;
212 if (!sp)
213 break;
214 if ((error = copyinstr((char *)(u_long)sp,
215 dp, len, &len)) != 0) {
216 if (error == ENAMETOOLONG)
217 error = E2BIG;
218 goto bad;
219 }
220 dp += len;
221 cpp++;
222 envc++;
223 }
224 }
225
226 dp = (char *) ALIGN(dp);
227
228 szsigcode = pack.ep_es->es_emul->e_esigcode -
229 pack.ep_es->es_emul->e_sigcode;
230
231 /* Now check if args & environ fit into new stack */
232 if (pack.ep_flags & EXEC_32)
233 len = ((argc + envc + 2 + pack.ep_es->es_arglen) *
234 sizeof(int) + sizeof(int) + dp + STACKGAPLEN +
235 szsigcode + sizeof(struct ps_strings)) - argp;
236 else
237 len = ((argc + envc + 2 + pack.ep_es->es_arglen) *
238 sizeof(char *) + sizeof(int) + dp + STACKGAPLEN +
239 szsigcode + sizeof(struct ps_strings)) - argp;
240
241 len = ALIGN(len); /* make the stack "safely" aligned */
242
243 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */
244 error = ENOMEM;
245 goto bad;
246 }
247
248 /* adjust "active stack depth" for process VSZ */
249 pack.ep_ssize = len; /* maybe should go elsewhere, but... */
250
251 /*
252 * Do whatever is necessary to prepare the address space
253 * for remapping. Note that this might replace the current
254 * vmspace with another!
255 */
256 uvmspace_exec(p, VM_MIN_ADDRESS, (vaddr_t)pack.ep_minsaddr);
257
258 /* Now map address space */
259 vm = p->p_vmspace;
260 vm->vm_taddr = (char *) pack.ep_taddr;
261 vm->vm_tsize = btoc(pack.ep_tsize);
262 vm->vm_daddr = (char *) pack.ep_daddr;
263 vm->vm_dsize = btoc(pack.ep_dsize);
264 vm->vm_ssize = btoc(pack.ep_ssize);
265 vm->vm_maxsaddr = (char *) pack.ep_maxsaddr;
266 vm->vm_minsaddr = (char *) pack.ep_minsaddr;
267
268 /* create the new process's VM space by running the vmcmds */
269 #ifdef DIAGNOSTIC
270 if (pack.ep_vmcmds.evs_used == 0)
271 panic("netbsd32_execve: no vmcmds");
272 #endif
273 for (i = 0; i < pack.ep_vmcmds.evs_used && !error; i++) {
274 struct exec_vmcmd *vcp;
275
276 vcp = &pack.ep_vmcmds.evs_cmds[i];
277 if (vcp->ev_flags & VMCMD_RELATIVE) {
278 #ifdef DIAGNOSTIC
279 if (base_vcp == NULL)
280 panic("netbsd32_execve: relative vmcmd with no base");
281 if (vcp->ev_flags & VMCMD_BASE)
282 panic("netbsd32_execve: illegal base & relative vmcmd");
283 #endif
284 vcp->ev_addr += base_vcp->ev_addr;
285 }
286 error = (*vcp->ev_proc)(p, vcp);
287 #ifdef DEBUG
288 if (error) {
289 int j;
290
291 for (j = 0; j <= i; j++)
292 printf("vmcmd[%d] = %#lx/%#lx @ %#lx\n", j,
293 vcp[j-i].ev_addr, vcp[j-i].ev_len,
294 vcp[j-i].ev_offset);
295 }
296 #endif
297 if (vcp->ev_flags & VMCMD_BASE)
298 base_vcp = vcp;
299 }
300
301 /* free the vmspace-creation commands, and release their references */
302 kill_vmcmds(&pack.ep_vmcmds);
303
304 /* if an error happened, deallocate and punt */
305 if (error) {
306 #ifdef DEBUG
307 printf("netbsd32_execve: vmcmd %i failed: %d\n", i-1, error);
308 #endif
309 goto exec_abort;
310 }
311
312 /* remember information about the process */
313 arginfo.ps_nargvstr = argc;
314 arginfo.ps_nenvstr = envc;
315
316 stack = (char *) (vm->vm_minsaddr - len);
317 /* Now copy argc, args & environ to new stack */
318 error = (*pack.ep_es->es_copyargs)(&pack, &arginfo,
319 &stack, argp);
320 if (error) {
321 #ifdef DEBUG
322 printf("netbsd32_execve: copyargs failed\n");
323 #endif
324 goto exec_abort;
325 }
326 /* restore the stack back to its original point */
327 stack = (char *) (vm->vm_minsaddr - len);
328
329 /* fill process ps_strings info */
330 p->p_psstr = (struct ps_strings *)(vm->vm_minsaddr -
331 sizeof(struct ps_strings));
332 p->p_psargv = offsetof(struct ps_strings, ps_argvstr);
333 p->p_psnargv = offsetof(struct ps_strings, ps_nargvstr);
334 p->p_psenv = offsetof(struct ps_strings, ps_envstr);
335 p->p_psnenv = offsetof(struct ps_strings, ps_nenvstr);
336
337 /* copy out the process's ps_strings structure */
338 if (copyout(&arginfo, (char *)p->p_psstr, sizeof(arginfo))) {
339 #ifdef DEBUG
340 printf("netbsd32_execve: ps_strings copyout failed\n");
341 #endif
342 goto exec_abort;
343 }
344
345 /* copy out the process's signal trapoline code */
346 if (szsigcode) {
347 if (copyout((char *)pack.ep_es->es_emul->e_sigcode,
348 p->p_sigctx.ps_sigcode = (char *)p->p_psstr - szsigcode,
349 szsigcode)) {
350 #ifdef DEBUG
351 printf("netbsd32_execve: sig trampoline copyout failed\n");
352 #endif
353 goto exec_abort;
354 }
355 #ifdef PMAP_NEED_PROCWR
356 /* This is code. Let the pmap do what is needed. */
357 pmap_procwr(p, (vaddr_t)p->p_sigacts->ps_sigcode, szsigcode);
358 #endif
359 }
360
361 stopprofclock(p); /* stop profiling */
362 fdcloseexec(p); /* handle close on exec */
363 execsigs(p); /* reset catched signals */
364 p->p_ctxlink = NULL; /* reset ucontext link */
365
366 /* set command name & other accounting info */
367 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN);
368 memcpy(p->p_comm, nid.ni_cnd.cn_nameptr, len);
369 p->p_comm[len] = 0;
370 p->p_acflag &= ~AFORK;
371
372 /* record proc's vnode, for use by procfs and others */
373 if (p->p_textvp)
374 vrele(p->p_textvp);
375 VREF(pack.ep_vp);
376 p->p_textvp = pack.ep_vp;
377
378 p->p_flag |= P_EXEC;
379 if (p->p_flag & P_PPWAIT) {
380 p->p_flag &= ~P_PPWAIT;
381 wakeup((caddr_t) p->p_pptr);
382 }
383
384 /*
385 * deal with set[ug]id.
386 * MNT_NOSUID has already been used to disable s[ug]id.
387 */
388 if ((p->p_flag & P_TRACED) == 0 &&
389
390 (((attr.va_mode & S_ISUID) != 0 &&
391 p->p_ucred->cr_uid != attr.va_uid) ||
392
393 ((attr.va_mode & S_ISGID) != 0 &&
394 p->p_ucred->cr_gid != attr.va_gid))) {
395 /*
396 * Mark the process as SUGID before we do
397 * anything that might block.
398 */
399 p_sugid(p);
400
401 p->p_ucred = crcopy(cred);
402 #ifdef KTRACE
403 /*
404 * If process is being ktraced, turn off - unless
405 * root set it.
406 */
407 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT))
408 ktrderef(p);
409 #endif
410 if (attr.va_mode & S_ISUID)
411 p->p_ucred->cr_uid = attr.va_uid;
412 if (attr.va_mode & S_ISGID)
413 p->p_ucred->cr_gid = attr.va_gid;
414 } else
415 p->p_flag &= ~P_SUGID;
416 p->p_cred->p_svuid = p->p_ucred->cr_uid;
417 p->p_cred->p_svgid = p->p_ucred->cr_gid;
418
419 doexechooks(p);
420
421 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS);
422
423 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
424 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
425 VOP_CLOSE(pack.ep_vp, FREAD, cred, p);
426 vput(pack.ep_vp);
427
428 /* setup new registers and do misc. setup. */
429 (*pack.ep_es->es_emul->e_setregs)(p, &pack, (u_long) stack);
430 if (pack.ep_es->es_setregs)
431 (*pack.ep_es->es_setregs)(p, &pack, (u_long) stack);
432
433 if (p->p_flag & P_TRACED)
434 psignal(p, SIGTRAP);
435
436 free(pack.ep_hdr, M_EXEC);
437
438 /*
439 * Call emulation specific exec hook. This can setup setup per-process
440 * p->p_emuldata or do any other per-process stuff an emulation needs.
441 *
442 * If we are executing process of different emulation than the
443 * original forked process, call e_proc_exit() of the old emulation
444 * first, then e_proc_exec() of new emulation. If the emulation is
445 * same, the exec hook code should deallocate any old emulation
446 * resources held previously by this process.
447 */
448 if (p->p_emul && p->p_emul->e_proc_exit
449 && p->p_emul != pack.ep_es->es_emul)
450 (*p->p_emul->e_proc_exit)(p);
451
452 /*
453 * Call exec hook. Emulation code may NOT store reference to anything
454 * from &pack.
455 */
456 if (pack.ep_es->es_emul->e_proc_exec)
457 (*pack.ep_es->es_emul->e_proc_exec)(p, &pack);
458
459 /* update p_emul, the old value is no longer needed */
460 p->p_emul = pack.ep_es->es_emul;
461
462 #ifdef KTRACE
463 if (KTRPOINT(p, KTR_EMUL))
464 ktremul(p);
465 #endif
466
467 #if defined(LKM) || defined(_LKM)
468 lockmgr(&exec_lock, LK_RELEASE, NULL);
469 #endif
470
471 return (EJUSTRETURN);
472
473 bad:
474 /* free the vmspace-creation commands, and release their references */
475 kill_vmcmds(&pack.ep_vmcmds);
476 /* kill any opened file descriptor, if necessary */
477 if (pack.ep_flags & EXEC_HASFD) {
478 pack.ep_flags &= ~EXEC_HASFD;
479 (void) fdrelease(p, pack.ep_fd);
480 }
481 /* close and put the exec'd file */
482 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
483 VOP_CLOSE(pack.ep_vp, FREAD, cred, p);
484 vput(pack.ep_vp);
485 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
486 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS);
487
488 freehdr:
489 #if defined(LKM) || defined(_LKM)
490 lockmgr(&exec_lock, LK_RELEASE, NULL);
491 #endif
492
493 free(pack.ep_hdr, M_EXEC);
494 return error;
495
496 exec_abort:
497 #if defined(LKM) || defined(_LKM)
498 lockmgr(&exec_lock, LK_RELEASE, NULL);
499 #endif
500
501 /*
502 * the old process doesn't exist anymore. exit gracefully.
503 * get rid of the (new) address space we have created, if any, get rid
504 * of our namei data and vnode, and exit noting failure
505 */
506 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS,
507 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS);
508 if (pack.ep_emul_arg)
509 FREE(pack.ep_emul_arg, M_TEMP);
510 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
511 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
512 VOP_CLOSE(pack.ep_vp, FREAD, cred, p);
513 vput(pack.ep_vp);
514 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS);
515 free(pack.ep_hdr, M_EXEC);
516 exit1(p, W_EXITCODE(error, SIGABRT));
517
518 /* NOTREACHED */
519 return 0;
520 }
521