netbsd32_execve.c revision 1.17.2.7 1 /* $NetBSD: netbsd32_execve.c,v 1.17.2.7 2005/04/01 14:29:36 skrll 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 1.17.2.7 2005/04/01 14:29:36 skrll 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/sa.h>
53 #include <sys/syscallargs.h>
54 #include <sys/proc.h>
55 #include <sys/acct.h>
56 #include <sys/exec.h>
57
58 #include <compat/netbsd32/netbsd32.h>
59 #include <compat/netbsd32/netbsd32_syscall.h>
60 #include <compat/netbsd32/netbsd32_syscallargs.h>
61
62 /* this is provided by kern/kern_exec.c */
63 extern u_int exec_maxhdrsz;
64 #if defined(LKM) || defined(_LKM)
65 extern struct lock exec_lock;
66 #endif
67
68 /*
69 * Need to completly reimplement this syscall due to argument copying.
70 */
71 /* ARGSUSED */
72 int
73 netbsd32_execve(l, v, retval)
74 struct lwp *l;
75 void *v;
76 register_t *retval;
77 {
78 struct netbsd32_execve_args /* {
79 syscallarg(const netbsd32_charp) path;
80 syscallarg(netbsd32_charpp) argp;
81 syscallarg(netbsd32_charpp) envp;
82 } */ *uap = v;
83 struct sys_execve_args ua;
84 caddr_t sg;
85 struct proc *p = l->l_proc;
86
87 NETBSD32TOP_UAP(path, const char);
88 NETBSD32TOP_UAP(argp, char *);
89 NETBSD32TOP_UAP(envp, char *);
90 sg = stackgap_init(p, 0);
91 CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
92
93 return netbsd32_execve2(l, &ua, retval);
94 }
95
96 int
97 netbsd32_execve2(l, uap, retval)
98 struct lwp *l;
99 struct sys_execve_args *uap;
100 register_t *retval;
101 {
102 /* Function args */
103 struct proc *p = l->l_proc;
104 int error, i;
105 struct exec_package pack;
106 struct nameidata nid;
107 struct vattr attr;
108 struct ucred *cred = p->p_ucred;
109 char *argp;
110 netbsd32_charp const *cpp;
111 char *dp;
112 netbsd32_charp sp;
113 long argc, envc;
114 size_t len;
115 char *stack;
116 struct ps_strings arginfo;
117 struct vmspace *vm;
118 char **tmpfap;
119 int szsigcode;
120 struct exec_vmcmd *base_vcp = NULL;
121
122 /*
123 * Init the namei data to point the file user's program name.
124 * This is done here rather than in check_exec(), so that it's
125 * possible to override this settings if any of makecmd/probe
126 * functions call check_exec() recursively - for example,
127 * see exec_script_makecmds().
128 */
129 NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
130
131 /*
132 * initialize the fields of the exec package.
133 */
134 pack.ep_name = SCARG(uap, path);
135 pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK);
136 pack.ep_hdrlen = exec_maxhdrsz;
137 pack.ep_hdrvalid = 0;
138 pack.ep_ndp = &nid;
139 pack.ep_emul_arg = NULL;
140 pack.ep_vmcmds.evs_cnt = 0;
141 pack.ep_vmcmds.evs_used = 0;
142 pack.ep_vap = &attr;
143 pack.ep_flags = 0;
144
145 #if defined(LKM) || defined(_LKM)
146 lockmgr(&exec_lock, LK_SHARED, NULL);
147 #endif
148
149 /* see if we can run it. */
150 if ((error = check_exec(l, &pack)) != 0)
151 goto freehdr;
152
153 /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */
154
155 /* allocate an argument buffer */
156 argp = (char *) uvm_km_alloc(exec_map, NCARGS, 0,
157 UVM_KMF_PAGEABLE|UVM_KMF_WAITVA);
158 #ifdef DIAGNOSTIC
159 if (argp == (vaddr_t) 0)
160 panic("netbsd32_execve: argp == NULL");
161 #endif
162 dp = argp;
163 argc = 0;
164
165 /* copy the fake args list, if there's one, freeing it as we go */
166 if (pack.ep_flags & EXEC_HASARGL) {
167 tmpfap = pack.ep_fa;
168 while (*tmpfap != NULL) {
169 char *cp;
170
171 cp = *tmpfap;
172 while (*cp)
173 *dp++ = *cp++;
174 dp++;
175
176 FREE(*tmpfap, M_EXEC);
177 tmpfap++; argc++;
178 }
179 FREE(pack.ep_fa, M_EXEC);
180 pack.ep_flags &= ~EXEC_HASARGL;
181 }
182
183 /* Now get argv & environment */
184 if (!(cpp = (netbsd32_charp *)SCARG(uap, argp))) {
185 error = EINVAL;
186 goto bad;
187 }
188
189 if (pack.ep_flags & EXEC_SKIPARG)
190 cpp++;
191
192 while (1) {
193 len = argp + ARG_MAX - dp;
194 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0)
195 goto bad;
196 if (!sp)
197 break;
198 if ((error = copyinstr((char *)(u_long)sp, dp,
199 len, &len)) != 0) {
200 if (error == ENAMETOOLONG)
201 error = E2BIG;
202 goto bad;
203 }
204 dp += len;
205 cpp++;
206 argc++;
207 }
208
209 envc = 0;
210 /* environment need not be there */
211 if ((cpp = (netbsd32_charp *)SCARG(uap, envp)) != NULL ) {
212 while (1) {
213 len = argp + ARG_MAX - dp;
214 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0)
215 goto bad;
216 if (!sp)
217 break;
218 if ((error = copyinstr((char *)(u_long)sp,
219 dp, len, &len)) != 0) {
220 if (error == ENAMETOOLONG)
221 error = E2BIG;
222 goto bad;
223 }
224 dp += len;
225 cpp++;
226 envc++;
227 }
228 }
229
230 dp = (char *) ALIGN(dp);
231
232 szsigcode = pack.ep_es->es_emul->e_esigcode -
233 pack.ep_es->es_emul->e_sigcode;
234
235 /* Now check if args & environ fit into new stack */
236 if (pack.ep_flags & EXEC_32)
237 len = ((argc + envc + 2 + pack.ep_es->es_arglen) *
238 sizeof(int) + sizeof(int) + dp + STACKGAPLEN +
239 szsigcode + sizeof(struct ps_strings)) - argp;
240 else
241 len = ((argc + envc + 2 + pack.ep_es->es_arglen) *
242 sizeof(char *) + sizeof(int) + dp + STACKGAPLEN +
243 szsigcode + sizeof(struct ps_strings)) - argp;
244
245 len = ALIGN(len); /* make the stack "safely" aligned */
246
247 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */
248 error = ENOMEM;
249 goto bad;
250 }
251
252 /* adjust "active stack depth" for process VSZ */
253 pack.ep_ssize = len; /* maybe should go elsewhere, but... */
254
255 /*
256 * Do whatever is necessary to prepare the address space
257 * for remapping. Note that this might replace the current
258 * vmspace with another!
259 */
260 uvmspace_exec(l, VM_MIN_ADDRESS, (vaddr_t)pack.ep_minsaddr);
261
262 /* Now map address space */
263 vm = p->p_vmspace;
264 vm->vm_taddr = (char *) pack.ep_taddr;
265 vm->vm_tsize = btoc(pack.ep_tsize);
266 vm->vm_daddr = (char *) pack.ep_daddr;
267 vm->vm_dsize = btoc(pack.ep_dsize);
268 vm->vm_ssize = btoc(pack.ep_ssize);
269 vm->vm_maxsaddr = (char *) pack.ep_maxsaddr;
270 vm->vm_minsaddr = (char *) pack.ep_minsaddr;
271
272 /* create the new process's VM space by running the vmcmds */
273 #ifdef DIAGNOSTIC
274 if (pack.ep_vmcmds.evs_used == 0)
275 panic("netbsd32_execve: no vmcmds");
276 #endif
277 for (i = 0; i < pack.ep_vmcmds.evs_used && !error; i++) {
278 struct exec_vmcmd *vcp;
279
280 vcp = &pack.ep_vmcmds.evs_cmds[i];
281 if (vcp->ev_flags & VMCMD_RELATIVE) {
282 #ifdef DIAGNOSTIC
283 if (base_vcp == NULL)
284 panic("netbsd32_execve: relative vmcmd with no base");
285 if (vcp->ev_flags & VMCMD_BASE)
286 panic("netbsd32_execve: illegal base & relative vmcmd");
287 #endif
288 vcp->ev_addr += base_vcp->ev_addr;
289 }
290 error = (*vcp->ev_proc)(l, vcp);
291 #ifdef DEBUG
292 if (error) {
293 int j;
294
295 for (j = 0; j <= i; j++)
296 printf("vmcmd[%d] = %#lx/%#lx @ %#lx\n", j,
297 vcp[j-i].ev_addr, vcp[j-i].ev_len,
298 vcp[j-i].ev_offset);
299 }
300 #endif
301 if (vcp->ev_flags & VMCMD_BASE)
302 base_vcp = vcp;
303 }
304
305 /* free the vmspace-creation commands, and release their references */
306 kill_vmcmds(&pack.ep_vmcmds);
307
308 /* if an error happened, deallocate and punt */
309 if (error) {
310 #ifdef DEBUG
311 printf("netbsd32_execve: vmcmd %i failed: %d\n", i-1, error);
312 #endif
313 goto exec_abort;
314 }
315
316 /* remember information about the process */
317 arginfo.ps_nargvstr = argc;
318 arginfo.ps_nenvstr = envc;
319
320 stack = (char *) (vm->vm_minsaddr - len);
321 /* Now copy argc, args & environ to new stack */
322 error = (*pack.ep_es->es_copyargs)(l, &pack, &arginfo,
323 &stack, argp);
324 if (error) {
325 #ifdef DEBUG
326 printf("netbsd32_execve: copyargs failed\n");
327 #endif
328 goto exec_abort;
329 }
330 /* restore the stack back to its original point */
331 stack = (char *) (vm->vm_minsaddr - len);
332
333 /* fill process ps_strings info */
334 p->p_psstr = (struct ps_strings *)(vm->vm_minsaddr -
335 sizeof(struct ps_strings));
336 p->p_psargv = offsetof(struct ps_strings, ps_argvstr);
337 p->p_psnargv = offsetof(struct ps_strings, ps_nargvstr);
338 p->p_psenv = offsetof(struct ps_strings, ps_envstr);
339 p->p_psnenv = offsetof(struct ps_strings, ps_nenvstr);
340
341 /* copy out the process's ps_strings structure */
342 if (copyout(&arginfo, (char *)p->p_psstr, sizeof(arginfo))) {
343 #ifdef DEBUG
344 printf("netbsd32_execve: ps_strings copyout failed\n");
345 #endif
346 goto exec_abort;
347 }
348
349 /* copy out the process's signal trapoline code */
350 if (szsigcode) {
351 if (copyout((char *)pack.ep_es->es_emul->e_sigcode,
352 p->p_sigctx.ps_sigcode = (char *)p->p_psstr - szsigcode,
353 szsigcode)) {
354 #ifdef DEBUG
355 printf("netbsd32_execve: sig trampoline copyout failed\n");
356 #endif
357 goto exec_abort;
358 }
359 #ifdef PMAP_NEED_PROCWR
360 /* This is code. Let the pmap do what is needed. */
361 pmap_procwr(p, (vaddr_t)p->p_sigctx.ps_sigcode, szsigcode);
362 #endif
363 }
364
365 stopprofclock(p); /* stop profiling */
366 fdcloseexec(l); /* handle close on exec */
367 execsigs(p); /* reset catched signals */
368 l->l_ctxlink = NULL; /* reset ucontext link */
369
370 /* set command name & other accounting info */
371 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN);
372 memcpy(p->p_comm, nid.ni_cnd.cn_nameptr, len);
373 p->p_comm[len] = 0;
374 p->p_acflag &= ~AFORK;
375
376 /* record proc's vnode, for use by procfs and others */
377 if (p->p_textvp)
378 vrele(p->p_textvp);
379 VREF(pack.ep_vp);
380 p->p_textvp = pack.ep_vp;
381
382 p->p_flag |= P_EXEC;
383 if (p->p_flag & P_PPWAIT) {
384 p->p_flag &= ~P_PPWAIT;
385 wakeup((caddr_t) p->p_pptr);
386 }
387
388 /*
389 * deal with set[ug]id.
390 * MNT_NOSUID has already been used to disable s[ug]id.
391 */
392 if ((p->p_flag & P_TRACED) == 0 &&
393
394 (((attr.va_mode & S_ISUID) != 0 &&
395 p->p_ucred->cr_uid != attr.va_uid) ||
396
397 ((attr.va_mode & S_ISGID) != 0 &&
398 p->p_ucred->cr_gid != attr.va_gid))) {
399 /*
400 * Mark the process as SUGID before we do
401 * anything that might block.
402 */
403 p_sugid(p);
404
405 p->p_ucred = crcopy(cred);
406 #ifdef KTRACE
407 /*
408 * If process is being ktraced, turn off - unless
409 * root set it.
410 */
411 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT))
412 ktrderef(p);
413 #endif
414 if (attr.va_mode & S_ISUID)
415 p->p_ucred->cr_uid = attr.va_uid;
416 if (attr.va_mode & S_ISGID)
417 p->p_ucred->cr_gid = attr.va_gid;
418 } else
419 p->p_flag &= ~P_SUGID;
420 p->p_cred->p_svuid = p->p_ucred->cr_uid;
421 p->p_cred->p_svgid = p->p_ucred->cr_gid;
422
423 doexechooks(p);
424
425 uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE);
426
427 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
428 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
429 VOP_CLOSE(pack.ep_vp, FREAD, cred, l);
430 vput(pack.ep_vp);
431
432 /* setup new registers and do misc. setup. */
433 (*pack.ep_es->es_emul->e_setregs)(l, &pack, (u_long) stack);
434 if (pack.ep_es->es_setregs)
435 (*pack.ep_es->es_setregs)(l, &pack, (u_long) stack);
436
437 if (p->p_flag & P_TRACED)
438 psignal(p, SIGTRAP);
439
440 free(pack.ep_hdr, M_EXEC);
441
442 /*
443 * Call emulation specific exec hook. This can setup setup per-process
444 * p->p_emuldata or do any other per-process stuff an emulation needs.
445 *
446 * If we are executing process of different emulation than the
447 * original forked process, call e_proc_exit() of the old emulation
448 * first, then e_proc_exec() of new emulation. If the emulation is
449 * same, the exec hook code should deallocate any old emulation
450 * resources held previously by this process.
451 */
452 if (p->p_emul && p->p_emul->e_proc_exit
453 && p->p_emul != pack.ep_es->es_emul)
454 (*p->p_emul->e_proc_exit)(p);
455
456 /*
457 * Call exec hook. Emulation code may NOT store reference to anything
458 * from &pack.
459 */
460 if (pack.ep_es->es_emul->e_proc_exec)
461 (*pack.ep_es->es_emul->e_proc_exec)(p, &pack);
462
463 /* update p_emul, the old value is no longer needed */
464 p->p_emul = pack.ep_es->es_emul;
465
466 /* ...and the same for p_execsw */
467 p->p_execsw = pack.ep_es;
468
469 #ifdef __HAVE_SYSCALL_INTERN
470 (*p->p_emul->e_syscall_intern)(p);
471 #endif
472 #ifdef KTRACE
473 if (KTRPOINT(p, KTR_EMUL))
474 ktremul(l);
475 #endif
476
477 #if defined(LKM) || defined(_LKM)
478 lockmgr(&exec_lock, LK_RELEASE, NULL);
479 #endif
480
481 return (EJUSTRETURN);
482
483 bad:
484 /* free the vmspace-creation commands, and release their references */
485 kill_vmcmds(&pack.ep_vmcmds);
486 /* kill any opened file descriptor, if necessary */
487 if (pack.ep_flags & EXEC_HASFD) {
488 pack.ep_flags &= ~EXEC_HASFD;
489 (void) fdrelease(l, pack.ep_fd);
490 }
491 /* close and put the exec'd file */
492 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
493 VOP_CLOSE(pack.ep_vp, FREAD, cred, l);
494 vput(pack.ep_vp);
495 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
496 uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE);
497
498 freehdr:
499 #if defined(LKM) || defined(_LKM)
500 lockmgr(&exec_lock, LK_RELEASE, NULL);
501 #endif
502
503 free(pack.ep_hdr, M_EXEC);
504 return error;
505
506 exec_abort:
507 #if defined(LKM) || defined(_LKM)
508 lockmgr(&exec_lock, LK_RELEASE, NULL);
509 #endif
510
511 /*
512 * the old process doesn't exist anymore. exit gracefully.
513 * get rid of the (new) address space we have created, if any, get rid
514 * of our namei data and vnode, and exit noting failure
515 */
516 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS,
517 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS);
518 if (pack.ep_emul_arg)
519 FREE(pack.ep_emul_arg, M_TEMP);
520 PNBUF_PUT(nid.ni_cnd.cn_pnbuf);
521 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY);
522 VOP_CLOSE(pack.ep_vp, FREAD, cred, l);
523 vput(pack.ep_vp);
524 uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE);
525 free(pack.ep_hdr, M_EXEC);
526 exit1(l, W_EXITCODE(error, SIGABRT));
527
528 /* NOTREACHED */
529 return 0;
530 }
531