netbsd32_execve.c revision 1.19
1/* $NetBSD: netbsd32_execve.c,v 1.19 2005/02/26 23:10:21 perry 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 1.19 2005/02/26 23:10:21 perry 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 */ 63extern u_int exec_maxhdrsz; 64#if defined(LKM) || defined(_LKM) 65extern struct lock exec_lock; 66#endif 67 68/* 69 * Need to completly reimplement this syscall due to argument copying. 70 */ 71/* ARGSUSED */ 72int 73netbsd32_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(p, &sg, SCARG(&ua, path)); 92 93 return netbsd32_execve2(l, &ua, retval); 94} 95 96int 97netbsd32_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), p); 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(p, &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_valloc_wait(exec_map, NCARGS); 157#ifdef DIAGNOSTIC 158 if (argp == (vaddr_t) 0) 159 panic("netbsd32_execve: argp == NULL"); 160#endif 161 dp = argp; 162 argc = 0; 163 164 /* copy the fake args list, if there's one, freeing it as we go */ 165 if (pack.ep_flags & EXEC_HASARGL) { 166 tmpfap = pack.ep_fa; 167 while (*tmpfap != NULL) { 168 char *cp; 169 170 cp = *tmpfap; 171 while (*cp) 172 *dp++ = *cp++; 173 dp++; 174 175 FREE(*tmpfap, M_EXEC); 176 tmpfap++; argc++; 177 } 178 FREE(pack.ep_fa, M_EXEC); 179 pack.ep_flags &= ~EXEC_HASARGL; 180 } 181 182 /* Now get argv & environment */ 183 if (!(cpp = (netbsd32_charp *)SCARG(uap, argp))) { 184 error = EINVAL; 185 goto bad; 186 } 187 188 if (pack.ep_flags & EXEC_SKIPARG) 189 cpp++; 190 191 while (1) { 192 len = argp + ARG_MAX - dp; 193 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 194 goto bad; 195 if (!sp) 196 break; 197 if ((error = copyinstr((char *)(u_long)sp, dp, 198 len, &len)) != 0) { 199 if (error == ENAMETOOLONG) 200 error = E2BIG; 201 goto bad; 202 } 203 dp += len; 204 cpp++; 205 argc++; 206 } 207 208 envc = 0; 209 /* environment need not be there */ 210 if ((cpp = (netbsd32_charp *)SCARG(uap, envp)) != NULL ) { 211 while (1) { 212 len = argp + ARG_MAX - dp; 213 if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) 214 goto bad; 215 if (!sp) 216 break; 217 if ((error = copyinstr((char *)(u_long)sp, 218 dp, len, &len)) != 0) { 219 if (error == ENAMETOOLONG) 220 error = E2BIG; 221 goto bad; 222 } 223 dp += len; 224 cpp++; 225 envc++; 226 } 227 } 228 229 dp = (char *) ALIGN(dp); 230 231 szsigcode = pack.ep_es->es_emul->e_esigcode - 232 pack.ep_es->es_emul->e_sigcode; 233 234 /* Now check if args & environ fit into new stack */ 235 if (pack.ep_flags & EXEC_32) 236 len = ((argc + envc + 2 + pack.ep_es->es_arglen) * 237 sizeof(int) + sizeof(int) + dp + STACKGAPLEN + 238 szsigcode + sizeof(struct ps_strings)) - argp; 239 else 240 len = ((argc + envc + 2 + pack.ep_es->es_arglen) * 241 sizeof(char *) + sizeof(int) + dp + STACKGAPLEN + 242 szsigcode + sizeof(struct ps_strings)) - argp; 243 244 len = ALIGN(len); /* make the stack "safely" aligned */ 245 246 if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ 247 error = ENOMEM; 248 goto bad; 249 } 250 251 /* adjust "active stack depth" for process VSZ */ 252 pack.ep_ssize = len; /* maybe should go elsewhere, but... */ 253 254 /* 255 * Do whatever is necessary to prepare the address space 256 * for remapping. Note that this might replace the current 257 * vmspace with another! 258 */ 259 uvmspace_exec(l, VM_MIN_ADDRESS, (vaddr_t)pack.ep_minsaddr); 260 261 /* Now map address space */ 262 vm = p->p_vmspace; 263 vm->vm_taddr = (char *) pack.ep_taddr; 264 vm->vm_tsize = btoc(pack.ep_tsize); 265 vm->vm_daddr = (char *) pack.ep_daddr; 266 vm->vm_dsize = btoc(pack.ep_dsize); 267 vm->vm_ssize = btoc(pack.ep_ssize); 268 vm->vm_maxsaddr = (char *) pack.ep_maxsaddr; 269 vm->vm_minsaddr = (char *) pack.ep_minsaddr; 270 271 /* create the new process's VM space by running the vmcmds */ 272#ifdef DIAGNOSTIC 273 if (pack.ep_vmcmds.evs_used == 0) 274 panic("netbsd32_execve: no vmcmds"); 275#endif 276 for (i = 0; i < pack.ep_vmcmds.evs_used && !error; i++) { 277 struct exec_vmcmd *vcp; 278 279 vcp = &pack.ep_vmcmds.evs_cmds[i]; 280 if (vcp->ev_flags & VMCMD_RELATIVE) { 281#ifdef DIAGNOSTIC 282 if (base_vcp == NULL) 283 panic("netbsd32_execve: relative vmcmd with no base"); 284 if (vcp->ev_flags & VMCMD_BASE) 285 panic("netbsd32_execve: illegal base & relative vmcmd"); 286#endif 287 vcp->ev_addr += base_vcp->ev_addr; 288 } 289 error = (*vcp->ev_proc)(p, vcp); 290#ifdef DEBUG 291 if (error) { 292 int j; 293 294 for (j = 0; j <= i; j++) 295 printf("vmcmd[%d] = %#lx/%#lx @ %#lx\n", j, 296 vcp[j-i].ev_addr, vcp[j-i].ev_len, 297 vcp[j-i].ev_offset); 298 } 299#endif 300 if (vcp->ev_flags & VMCMD_BASE) 301 base_vcp = vcp; 302 } 303 304 /* free the vmspace-creation commands, and release their references */ 305 kill_vmcmds(&pack.ep_vmcmds); 306 307 /* if an error happened, deallocate and punt */ 308 if (error) { 309#ifdef DEBUG 310 printf("netbsd32_execve: vmcmd %i failed: %d\n", i-1, error); 311#endif 312 goto exec_abort; 313 } 314 315 /* remember information about the process */ 316 arginfo.ps_nargvstr = argc; 317 arginfo.ps_nenvstr = envc; 318 319 stack = (char *) (vm->vm_minsaddr - len); 320 /* Now copy argc, args & environ to new stack */ 321 error = (*pack.ep_es->es_copyargs)(p, &pack, &arginfo, 322 &stack, argp); 323 if (error) { 324#ifdef DEBUG 325 printf("netbsd32_execve: copyargs failed\n"); 326#endif 327 goto exec_abort; 328 } 329 /* restore the stack back to its original point */ 330 stack = (char *) (vm->vm_minsaddr - len); 331 332 /* fill process ps_strings info */ 333 p->p_psstr = (struct ps_strings *)(vm->vm_minsaddr - 334 sizeof(struct ps_strings)); 335 p->p_psargv = offsetof(struct ps_strings, ps_argvstr); 336 p->p_psnargv = offsetof(struct ps_strings, ps_nargvstr); 337 p->p_psenv = offsetof(struct ps_strings, ps_envstr); 338 p->p_psnenv = offsetof(struct ps_strings, ps_nenvstr); 339 340 /* copy out the process's ps_strings structure */ 341 if (copyout(&arginfo, (char *)p->p_psstr, sizeof(arginfo))) { 342#ifdef DEBUG 343 printf("netbsd32_execve: ps_strings copyout failed\n"); 344#endif 345 goto exec_abort; 346 } 347 348 /* copy out the process's signal trapoline code */ 349 if (szsigcode) { 350 if (copyout((char *)pack.ep_es->es_emul->e_sigcode, 351 p->p_sigctx.ps_sigcode = (char *)p->p_psstr - szsigcode, 352 szsigcode)) { 353#ifdef DEBUG 354 printf("netbsd32_execve: sig trampoline copyout failed\n"); 355#endif 356 goto exec_abort; 357 } 358#ifdef PMAP_NEED_PROCWR 359 /* This is code. Let the pmap do what is needed. */ 360 pmap_procwr(p, (vaddr_t)p->p_sigctx.ps_sigcode, szsigcode); 361#endif 362 } 363 364 stopprofclock(p); /* stop profiling */ 365 fdcloseexec(p); /* handle close on exec */ 366 execsigs(p); /* reset catched signals */ 367 l->l_ctxlink = NULL; /* reset ucontext link */ 368 369 /* set command name & other accounting info */ 370 len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); 371 memcpy(p->p_comm, nid.ni_cnd.cn_nameptr, len); 372 p->p_comm[len] = 0; 373 p->p_acflag &= ~AFORK; 374 375 /* record proc's vnode, for use by procfs and others */ 376 if (p->p_textvp) 377 vrele(p->p_textvp); 378 VREF(pack.ep_vp); 379 p->p_textvp = pack.ep_vp; 380 381 p->p_flag |= P_EXEC; 382 if (p->p_flag & P_PPWAIT) { 383 p->p_flag &= ~P_PPWAIT; 384 wakeup((caddr_t) p->p_pptr); 385 } 386 387 /* 388 * deal with set[ug]id. 389 * MNT_NOSUID has already been used to disable s[ug]id. 390 */ 391 if ((p->p_flag & P_TRACED) == 0 && 392 393 (((attr.va_mode & S_ISUID) != 0 && 394 p->p_ucred->cr_uid != attr.va_uid) || 395 396 ((attr.va_mode & S_ISGID) != 0 && 397 p->p_ucred->cr_gid != attr.va_gid))) { 398 /* 399 * Mark the process as SUGID before we do 400 * anything that might block. 401 */ 402 p_sugid(p); 403 404 p->p_ucred = crcopy(cred); 405#ifdef KTRACE 406 /* 407 * If process is being ktraced, turn off - unless 408 * root set it. 409 */ 410 if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) 411 ktrderef(p); 412#endif 413 if (attr.va_mode & S_ISUID) 414 p->p_ucred->cr_uid = attr.va_uid; 415 if (attr.va_mode & S_ISGID) 416 p->p_ucred->cr_gid = attr.va_gid; 417 } else 418 p->p_flag &= ~P_SUGID; 419 p->p_cred->p_svuid = p->p_ucred->cr_uid; 420 p->p_cred->p_svgid = p->p_ucred->cr_gid; 421 422 doexechooks(p); 423 424 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 425 426 PNBUF_PUT(nid.ni_cnd.cn_pnbuf); 427 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); 428 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 429 vput(pack.ep_vp); 430 431 /* setup new registers and do misc. setup. */ 432 (*pack.ep_es->es_emul->e_setregs)(l, &pack, (u_long) stack); 433 if (pack.ep_es->es_setregs) 434 (*pack.ep_es->es_setregs)(l, &pack, (u_long) stack); 435 436 if (p->p_flag & P_TRACED) 437 psignal(p, SIGTRAP); 438 439 free(pack.ep_hdr, M_EXEC); 440 441 /* 442 * Call emulation specific exec hook. This can setup setup per-process 443 * p->p_emuldata or do any other per-process stuff an emulation needs. 444 * 445 * If we are executing process of different emulation than the 446 * original forked process, call e_proc_exit() of the old emulation 447 * first, then e_proc_exec() of new emulation. If the emulation is 448 * same, the exec hook code should deallocate any old emulation 449 * resources held previously by this process. 450 */ 451 if (p->p_emul && p->p_emul->e_proc_exit 452 && p->p_emul != pack.ep_es->es_emul) 453 (*p->p_emul->e_proc_exit)(p); 454 455 /* 456 * Call exec hook. Emulation code may NOT store reference to anything 457 * from &pack. 458 */ 459 if (pack.ep_es->es_emul->e_proc_exec) 460 (*pack.ep_es->es_emul->e_proc_exec)(p, &pack); 461 462 /* update p_emul, the old value is no longer needed */ 463 p->p_emul = pack.ep_es->es_emul; 464 465 /* ...and the same for p_execsw */ 466 p->p_execsw = pack.ep_es; 467 468#ifdef __HAVE_SYSCALL_INTERN 469 (*p->p_emul->e_syscall_intern)(p); 470#endif 471#ifdef KTRACE 472 if (KTRPOINT(p, KTR_EMUL)) 473 ktremul(p); 474#endif 475 476#if defined(LKM) || defined(_LKM) 477 lockmgr(&exec_lock, LK_RELEASE, NULL); 478#endif 479 480 return (EJUSTRETURN); 481 482bad: 483 /* free the vmspace-creation commands, and release their references */ 484 kill_vmcmds(&pack.ep_vmcmds); 485 /* kill any opened file descriptor, if necessary */ 486 if (pack.ep_flags & EXEC_HASFD) { 487 pack.ep_flags &= ~EXEC_HASFD; 488 (void) fdrelease(p, pack.ep_fd); 489 } 490 /* close and put the exec'd file */ 491 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); 492 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 493 vput(pack.ep_vp); 494 PNBUF_PUT(nid.ni_cnd.cn_pnbuf); 495 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 496 497freehdr: 498#if defined(LKM) || defined(_LKM) 499 lockmgr(&exec_lock, LK_RELEASE, NULL); 500#endif 501 502 free(pack.ep_hdr, M_EXEC); 503 return error; 504 505exec_abort: 506#if defined(LKM) || defined(_LKM) 507 lockmgr(&exec_lock, LK_RELEASE, NULL); 508#endif 509 510 /* 511 * the old process doesn't exist anymore. exit gracefully. 512 * get rid of the (new) address space we have created, if any, get rid 513 * of our namei data and vnode, and exit noting failure 514 */ 515 uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, 516 VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); 517 if (pack.ep_emul_arg) 518 FREE(pack.ep_emul_arg, M_TEMP); 519 PNBUF_PUT(nid.ni_cnd.cn_pnbuf); 520 vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); 521 VOP_CLOSE(pack.ep_vp, FREAD, cred, p); 522 vput(pack.ep_vp); 523 uvm_km_free_wakeup(exec_map, (vaddr_t) argp, NCARGS); 524 free(pack.ep_hdr, M_EXEC); 525 exit1(l, W_EXITCODE(error, SIGABRT)); 526 527 /* NOTREACHED */ 528 return 0; 529} 530