1 /* $NetBSD: linux_exec.c,v 1.89 2006/11/16 01:32:42 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1994, 1995, 1998, 2000 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, Eric Haszlakiewicz and 9 * Thor Lancelot Simon. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> 41 __KERNEL_RCSID(0, "$NetBSD: linux_exec.c,v 1.89 2006/11/16 01:32:42 christos Exp $"); 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/proc.h> 47 #include <sys/malloc.h> 48 #include <sys/namei.h> 49 #include <sys/vnode.h> 50 #include <sys/mount.h> 51 #include <sys/exec.h> 52 #include <sys/exec_elf.h> 53 54 #include <sys/mman.h> 55 #include <sys/sa.h> 56 #include <sys/syscallargs.h> 57 58 #include <sys/ptrace.h> /* For proc_reparent() */ 59 60 #include <uvm/uvm_extern.h> 61 62 #include <machine/cpu.h> 63 #include <machine/reg.h> 64 65 #include <compat/linux/common/linux_types.h> 66 #include <compat/linux/common/linux_signal.h> 67 #include <compat/linux/common/linux_util.h> 68 #include <compat/linux/common/linux_sched.h> 69 #include <compat/linux/common/linux_machdep.h> 70 #include <compat/linux/common/linux_exec.h> 71 #include <compat/linux/common/linux_futex.h> 72 73 #include <compat/linux/linux_syscallargs.h> 74 #include <compat/linux/linux_syscall.h> 75 #include <compat/linux/common/linux_misc.h> 76 #include <compat/linux/common/linux_errno.h> 77 #include <compat/linux/common/linux_emuldata.h> 78 79 extern struct sysent linux_sysent[]; 80 extern const char * const linux_syscallnames[]; 81 extern char linux_sigcode[], linux_esigcode[]; 82 83 static void linux_e_proc_exec __P((struct proc *, struct exec_package *)); 84 static void linux_e_proc_fork __P((struct proc *, struct proc *, int)); 85 static void linux_e_proc_exit __P((struct proc *)); 86 static void linux_e_proc_init __P((struct proc *, struct proc *, int)); 87 88 #ifdef LINUX_NPTL 89 void linux_userret __P((struct lwp *, void *)); 90 #endif 91 92 /* 93 * Execve(2). Just check the alternate emulation path, and pass it on 94 * to the NetBSD execve(). 95 */ 96 int 97 linux_sys_execve(l, v, retval) 98 struct lwp *l; 99 void *v; 100 register_t *retval; 101 { 102 struct linux_sys_execve_args /* { 103 syscallarg(const char *) path; 104 syscallarg(char **) argv; 105 syscallarg(char **) envp; 106 } */ *uap = v; 107 struct proc *p = l->l_proc; 108 struct sys_execve_args ap; 109 caddr_t sg; 110 111 sg = stackgap_init(p, 0); 112 CHECK_ALT_EXIST(l, &sg, SCARG(uap, path)); 113 114 SCARG(&ap, path) = SCARG(uap, path); 115 SCARG(&ap, argp) = SCARG(uap, argp); 116 SCARG(&ap, envp) = SCARG(uap, envp); 117 118 return sys_execve(l, &ap, retval); 119 } 120 121 /* 122 * Emulation switch. 123 */ 124 125 struct uvm_object *emul_linux_object; 126 127 const struct emul emul_linux = { 128 "linux", 129 "/emul/linux", 130 #ifndef __HAVE_MINIMAL_EMUL 131 0, 132 (const int *)native_to_linux_errno, 133 LINUX_SYS_syscall, 134 LINUX_SYS_NSYSENT, 135 #endif 136 linux_sysent, 137 linux_syscallnames, 138 linux_sendsig, 139 linux_trapsignal, 140 NULL, 141 linux_sigcode, 142 linux_esigcode, 143 &emul_linux_object, 144 linux_setregs, 145 linux_e_proc_exec, 146 linux_e_proc_fork, 147 linux_e_proc_exit, 148 NULL, 149 NULL, 150 #ifdef __HAVE_SYSCALL_INTERN 151 linux_syscall_intern, 152 #else 153 #error Implement __HAVE_SYSCALL_INTERN for this platform 154 #endif 155 NULL, 156 NULL, 157 158 uvm_default_mapaddr, 159 160 linux_usertrap, 161 NULL, 162 }; 163 164 static void 165 linux_e_proc_init(p, parent, forkflags) 166 struct proc *p, *parent; 167 int forkflags; 168 { 169 struct linux_emuldata *e = p->p_emuldata; 170 struct linux_emuldata_shared *s; 171 struct linux_emuldata *ep = NULL; 172 173 if (!e) { 174 /* allocate new Linux emuldata */ 175 MALLOC(e, void *, sizeof(struct linux_emuldata), 176 M_EMULDATA, M_WAITOK); 177 } else { 178 e->s->refs--; 179 if (e->s->refs == 0) 180 FREE(e->s, M_EMULDATA); 181 } 182 183 memset(e, '\0', sizeof(struct linux_emuldata)); 184 185 e->proc = p; 186 187 if (parent) 188 ep = parent->p_emuldata; 189 190 if (forkflags & FORK_SHAREVM) { 191 #ifdef DIAGNOSTIC 192 if (ep == NULL) { 193 killproc(p, "FORK_SHAREVM while emuldata is NULL\n"); 194 FREE(e, M_EMULDATA); 195 return; 196 } 197 #endif 198 s = ep->s; 199 s->refs++; 200 } else { 201 struct vmspace *vm; 202 203 MALLOC(s, void *, sizeof(struct linux_emuldata_shared), 204 M_EMULDATA, M_WAITOK); 205 s->refs = 1; 206 207 /* 208 * Set the process idea of the break to the real value. 209 * For fork, we use parent's vmspace since our's 210 * is not setup at the time of this call and is going 211 * to be copy of parent's anyway. For exec, just 212 * use our own vmspace. 213 */ 214 vm = (parent) ? parent->p_vmspace : p->p_vmspace; 215 s->p_break = vm->vm_daddr + ctob(vm->vm_dsize); 216 217 /* 218 * Linux threads are emulated as NetBSD processes (not lwp) 219 * We use native PID for Linux TID. The Linux TID is the 220 * PID of the first process in the group. It is stored 221 * here 222 */ 223 s->group_pid = p->p_pid; 224 225 /* 226 * Initialize the list of threads in the group 227 */ 228 LIST_INIT(&s->threads); 229 230 s->xstat = 0; 231 s->flags = 0; 232 } 233 234 e->s = s; 235 236 /* 237 * Add this thread in the group thread list 238 */ 239 LIST_INSERT_HEAD(&s->threads, e, threads); 240 241 #ifdef LINUX_NPTL 242 if (ep != NULL) { 243 e->parent_tidptr = ep->parent_tidptr; 244 e->child_tidptr = ep->child_tidptr; 245 e->clone_flags = ep->clone_flags; 246 } 247 #endif /* LINUX_NPTL */ 248 249 p->p_emuldata = e; 250 } 251 252 /* 253 * Allocate new per-process structures. Called when executing Linux 254 * process. We can reuse the old emuldata - if it's not null, 255 * the executed process is of same emulation as original forked one. 256 */ 257 static void 258 linux_e_proc_exec(struct proc *p, struct exec_package *epp) 259 { 260 /* exec, use our vmspace */ 261 linux_e_proc_init(p, NULL, 0); 262 } 263 264 /* 265 * Emulation per-process exit hook. 266 */ 267 static void 268 linux_e_proc_exit(p) 269 struct proc *p; 270 { 271 struct linux_emuldata *e = p->p_emuldata; 272 273 #ifdef LINUX_NPTL 274 linux_nptl_proc_exit(p); 275 #endif 276 /* Remove the thread for the group thread list */ 277 LIST_REMOVE(e, threads); 278 279 /* free Linux emuldata and set the pointer to null */ 280 e->s->refs--; 281 if (e->s->refs == 0) 282 FREE(e->s, M_EMULDATA); 283 FREE(e, M_EMULDATA); 284 p->p_emuldata = NULL; 285 } 286 287 /* 288 * Emulation fork hook. 289 */ 290 static void 291 linux_e_proc_fork(p, parent, forkflags) 292 struct proc *p, *parent; 293 int forkflags; 294 { 295 /* 296 * The new process might share some vmspace-related stuff 297 * with parent, depending on fork flags (CLONE_VM et.al). 298 * Force allocation of new base emuldata, and share the 299 * VM-related parts only if necessary. 300 */ 301 p->p_emuldata = NULL; 302 linux_e_proc_init(p, parent, forkflags); 303 304 #ifdef LINUX_NPTL 305 linux_nptl_proc_fork(p, parent, (*linux_userret)); 306 #endif 307 308 return; 309 } 310 311 #ifdef LINUX_NPTL 312 void 313 linux_userret(l, arg) 314 struct lwp *l; 315 void *arg; 316 { 317 struct proc *p = l->l_proc; 318 struct linux_emuldata *led = p->p_emuldata; 319 int error; 320 321 p->p_userret = NULL; 322 323 /* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory */ 324 if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) { 325 if ((error = copyout(&l->l_proc->p_pid, 326 led->child_tidptr, sizeof(l->l_proc->p_pid))) != 0) 327 printf("linux_userret: LINUX_CLONE_CHILD_SETTID " 328 "failed (led->child_tidptr = %p, p->p_pid = %d)\n", 329 led->child_tidptr, p->p_pid); 330 } 331 332 /* LINUX_CLONE_SETTLS: allocate a new TLS */ 333 if (led->clone_flags & LINUX_CLONE_SETTLS) { 334 if (linux_set_newtls(l, linux_get_newtls(l)) != 0) 335 printf("linux_userret: linux_set_tls failed"); 336 } 337 338 return; 339 } 340 341 void 342 linux_nptl_proc_exit(p) 343 struct proc *p; 344 { 345 struct linux_emuldata *e = p->p_emuldata; 346 int s; 347 348 /* 349 * Check if we are a thread group leader victim of another 350 * thread doing exit_group(). If we are, change the exit code. 351 */ 352 if ((e->s->group_pid == p->p_pid) && 353 (e->s->flags & LINUX_LES_INEXITGROUP)) { 354 p->p_xstat = e->s->xstat; 355 } 356 357 /* 358 * Members of the thread groups others than the leader should 359 * exit quietely: no zombie stage, no signal. We do that by 360 * reparenting to init. init will collect us and nobody will 361 * notice what happened. 362 */ 363 #ifdef DEBUG_LINUX 364 printf("%s:%d e->s->group_pid = %d, p->p_pid = %d, flags = 0x%x\n", 365 __func__, __LINE__, e->s->group_pid, p->p_pid, e->s->flags); 366 #endif 367 if (e->s->group_pid != p->p_pid) { 368 wakeup(initproc); 369 SCHED_LOCK(s); 370 proc_reparent(p, initproc); 371 SCHED_UNLOCK(s); 372 } 373 374 /* Emulate LINUX_CLONE_CHILD_CLEARTID */ 375 if (e->clear_tid != NULL) { 376 int error; 377 int null = 0; 378 struct linux_sys_futex_args cup; 379 register_t retval; 380 struct lwp *l; 381 382 error = copyout(&null, e->clear_tid, sizeof(null)); 383 #ifdef DEBUG_LINUX 384 if (error != 0) 385 printf("%s: cannot clear TID\n", __func__); 386 #endif 387 388 l = proc_representative_lwp(p); 389 SCARG(&cup, uaddr) = e->clear_tid; 390 SCARG(&cup, op) = LINUX_FUTEX_WAKE; 391 SCARG(&cup, val) = 0x7fffffff; /* Awake everyone */ 392 SCARG(&cup, timeout) = NULL; 393 SCARG(&cup, uaddr2) = NULL; 394 SCARG(&cup, val3) = 0; 395 if ((error = linux_sys_futex(l, &cup, &retval)) != 0) 396 printf("%s: linux_sys_futex failed\n", __func__); 397 } 398 399 return; 400 } 401 402 void 403 linux_nptl_proc_fork(p, parent, luserret) 404 struct proc *p; 405 struct proc *parent; 406 void (luserret)(struct lwp *, void *); 407 { 408 #ifdef LINUX_NPTL 409 struct linux_emuldata *e; 410 #endif 411 e = p->p_emuldata; 412 413 /* LINUX_CLONE_CHILD_CLEARTID: clear TID in child's memory on exit() */ 414 if (e->clone_flags & LINUX_CLONE_CHILD_CLEARTID) 415 e->clear_tid = e->child_tidptr; 416 417 /* LINUX_CLONE_PARENT_SETTID: set child's TID in parent's memory */ 418 if (e->clone_flags & LINUX_CLONE_PARENT_SETTID) { 419 if (copyout_proc(parent, &p->p_pid, 420 e->parent_tidptr, sizeof(p->p_pid)) != 0) 421 printf("%s: LINUX_CLONE_PARENT_SETTID " 422 "failed (e->parent_tidptr = %p, " 423 "parent->p_pid = %d, p->p_pid = %d)\n", 424 __func__, e->parent_tidptr, 425 parent->p_pid, p->p_pid); 426 } 427 428 /* 429 * CLONE_CHILD_SETTID and LINUX_CLONE_SETTLS require child's VM 430 * setup to be completed, we postpone them until userret time. 431 */ 432 if (e->clone_flags & 433 (LINUX_CLONE_CHILD_CLEARTID | LINUX_CLONE_SETTLS)) 434 p->p_userret = (*luserret); 435 436 return; 437 } 438 439 void 440 linux_nptl_proc_init(p, parent) 441 struct proc *p; 442 struct proc *parent; 443 { 444 struct linux_emuldata *e = p->p_emuldata; 445 struct linux_emuldata *ep; 446 447 if ((parent != NULL) && (parent->p_emuldata != NULL)) { 448 ep = parent->p_emuldata; 449 450 e->parent_tidptr = ep->parent_tidptr; 451 e->child_tidptr = ep->child_tidptr; 452 e->clone_flags = ep->clone_flags; 453 } 454 455 return; 456 } 457 458 459 #endif /* LINUX_NPTL */ 460