linux_exec.c revision 1.105.2.1
1 /* $NetBSD: linux_exec.c,v 1.105.2.1 2008/05/10 23:48:55 wrstuden Exp $ */ 2 3 /*- 4 * Copyright (c) 1994, 1995, 1998, 2000, 2007, 2008 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 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: linux_exec.c,v 1.105.2.1 2008/05/10 23:48:55 wrstuden Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/proc.h> 40 #include <sys/malloc.h> 41 #include <sys/namei.h> 42 #include <sys/vnode.h> 43 #include <sys/mount.h> 44 #include <sys/exec.h> 45 #include <sys/exec_elf.h> 46 47 #include <sys/mman.h> 48 #include <sys/sa.h> 49 #include <sys/syscallargs.h> 50 51 #include <sys/ptrace.h> /* For proc_reparent() */ 52 53 #include <uvm/uvm_extern.h> 54 55 #include <sys/cpu.h> 56 #include <machine/reg.h> 57 58 #include <compat/linux/common/linux_types.h> 59 #include <compat/linux/common/linux_signal.h> 60 #include <compat/linux/common/linux_util.h> 61 #include <compat/linux/common/linux_sched.h> 62 #include <compat/linux/common/linux_machdep.h> 63 #include <compat/linux/common/linux_exec.h> 64 #include <compat/linux/common/linux_futex.h> 65 #include <compat/linux/common/linux_ipc.h> 66 #include <compat/linux/common/linux_sem.h> 67 68 #include <compat/linux/linux_syscallargs.h> 69 #include <compat/linux/linux_syscall.h> 70 #include <compat/linux/common/linux_misc.h> 71 #include <compat/linux/common/linux_errno.h> 72 #include <compat/linux/common/linux_emuldata.h> 73 74 extern struct sysent linux_sysent[]; 75 extern const char * const linux_syscallnames[]; 76 extern char linux_sigcode[], linux_esigcode[]; 77 78 static void linux_e_proc_exec(struct proc *, struct exec_package *); 79 static void linux_e_proc_fork(struct proc *, struct proc *, int); 80 static void linux_e_proc_exit(struct proc *); 81 static void linux_e_proc_init(struct proc *, struct proc *, int); 82 83 #ifdef LINUX_NPTL 84 void linux_userret(void); 85 #endif 86 87 /* 88 * Emulation switch. 89 */ 90 91 struct uvm_object *emul_linux_object; 92 93 const struct emul emul_linux = { 94 "linux", 95 "/emul/linux", 96 #ifndef __HAVE_MINIMAL_EMUL 97 0, 98 (const int *)native_to_linux_errno, 99 LINUX_SYS_syscall, 100 LINUX_SYS_NSYSENT, 101 #endif 102 linux_sysent, 103 linux_syscallnames, 104 linux_sendsig, 105 linux_trapsignal, 106 NULL, 107 linux_sigcode, 108 linux_esigcode, 109 &emul_linux_object, 110 linux_setregs, 111 linux_e_proc_exec, 112 linux_e_proc_fork, 113 linux_e_proc_exit, 114 NULL, 115 NULL, 116 #ifdef __HAVE_SYSCALL_INTERN 117 linux_syscall_intern, 118 #else 119 #error Implement __HAVE_SYSCALL_INTERN for this platform 120 #endif 121 NULL, 122 NULL, 123 124 uvm_default_mapaddr, 125 126 linux_usertrap, 127 NULL, /* e_sa */ 128 0, 129 NULL, /* e_startlwp */ 130 }; 131 132 static void 133 linux_e_proc_init(p, parent, forkflags) 134 struct proc *p, *parent; 135 int forkflags; 136 { 137 struct linux_emuldata *e = p->p_emuldata; 138 struct linux_emuldata_shared *s; 139 struct linux_emuldata *ep = NULL; 140 141 if (!e) { 142 /* allocate new Linux emuldata */ 143 MALLOC(e, void *, sizeof(struct linux_emuldata), 144 M_EMULDATA, M_WAITOK); 145 } else { 146 mutex_enter(proc_lock); 147 e->s->refs--; 148 if (e->s->refs == 0) 149 FREE(e->s, M_EMULDATA); 150 mutex_exit(proc_lock); 151 } 152 153 memset(e, '\0', sizeof(struct linux_emuldata)); 154 155 e->proc = p; 156 157 if (parent) 158 ep = parent->p_emuldata; 159 160 if (forkflags & FORK_SHAREVM) { 161 mutex_enter(proc_lock); 162 #ifdef DIAGNOSTIC 163 if (ep == NULL) { 164 killproc(p, "FORK_SHAREVM while emuldata is NULL\n"); 165 mutex_exit(proc_lock); 166 FREE(e, M_EMULDATA); 167 return; 168 } 169 #endif 170 s = ep->s; 171 s->refs++; 172 } else { 173 struct vmspace *vm; 174 175 MALLOC(s, void *, sizeof(struct linux_emuldata_shared), 176 M_EMULDATA, M_WAITOK); 177 s->refs = 1; 178 179 /* 180 * Set the process idea of the break to the real value. 181 * For fork, we use parent's vmspace since our's 182 * is not setup at the time of this call and is going 183 * to be copy of parent's anyway. For exec, just 184 * use our own vmspace. 185 */ 186 vm = (parent) ? parent->p_vmspace : p->p_vmspace; 187 s->p_break = (char *)vm->vm_daddr + ctob(vm->vm_dsize); 188 189 /* 190 * Linux threads are emulated as NetBSD processes (not lwp) 191 * We use native PID for Linux TID. The Linux TID is the 192 * PID of the first process in the group. It is stored 193 * here 194 */ 195 s->group_pid = p->p_pid; 196 197 /* 198 * Initialize the list of threads in the group 199 */ 200 LIST_INIT(&s->threads); 201 202 s->xstat = 0; 203 s->flags = 0; 204 mutex_enter(proc_lock); 205 } 206 207 e->s = s; 208 209 /* 210 * Add this thread in the group thread list 211 */ 212 LIST_INSERT_HEAD(&s->threads, e, threads); 213 214 #ifdef LINUX_NPTL 215 if (ep != NULL) { 216 e->parent_tidptr = ep->parent_tidptr; 217 e->child_tidptr = ep->child_tidptr; 218 e->clone_flags = ep->clone_flags; 219 } 220 #endif /* LINUX_NPTL */ 221 222 mutex_exit(proc_lock); 223 p->p_emuldata = e; 224 } 225 226 /* 227 * Allocate new per-process structures. Called when executing Linux 228 * process. We can reuse the old emuldata - if it's not null, 229 * the executed process is of same emulation as original forked one. 230 */ 231 static void 232 linux_e_proc_exec(struct proc *p, struct exec_package *epp) 233 { 234 235 /* exec, use our vmspace */ 236 linux_e_proc_init(p, NULL, 0); 237 } 238 239 /* 240 * Emulation per-process exit hook. 241 */ 242 static void 243 linux_e_proc_exit(struct proc *p) 244 { 245 struct linux_emuldata *e = p->p_emuldata; 246 247 #ifdef LINUX_NPTL 248 linux_nptl_proc_exit(p); 249 #endif 250 251 /* Remove the thread for the group thread list */ 252 mutex_enter(proc_lock); 253 LIST_REMOVE(e, threads); 254 255 /* free Linux emuldata and set the pointer to null */ 256 e->s->refs--; 257 if (e->s->refs == 0) 258 FREE(e->s, M_EMULDATA); 259 p->p_emuldata = NULL; 260 mutex_exit(proc_lock); 261 FREE(e, M_EMULDATA); 262 } 263 264 /* 265 * Emulation fork hook. 266 */ 267 static void 268 linux_e_proc_fork(p, parent, forkflags) 269 struct proc *p, *parent; 270 int forkflags; 271 { 272 273 /* 274 * The new process might share some vmspace-related stuff 275 * with parent, depending on fork flags (CLONE_VM et.al). 276 * Force allocation of new base emuldata, and share the 277 * VM-related parts only if necessary. 278 */ 279 p->p_emuldata = NULL; 280 linux_e_proc_init(p, parent, forkflags); 281 282 #ifdef LINUX_NPTL 283 linux_nptl_proc_fork(p, parent, linux_userret); 284 #endif 285 286 return; 287 } 288 289 #ifdef LINUX_NPTL 290 void 291 linux_userret(void) 292 { 293 struct lwp *l = curlwp; 294 struct proc *p = l->l_proc; 295 struct linux_emuldata *led = p->p_emuldata; 296 int error; 297 298 /* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory */ 299 if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) { 300 if ((error = copyout(&l->l_proc->p_pid, 301 led->child_tidptr, sizeof(l->l_proc->p_pid))) != 0) 302 printf("linux_userret: LINUX_CLONE_CHILD_SETTID " 303 "failed (led->child_tidptr = %p, p->p_pid = %d)\n", 304 led->child_tidptr, p->p_pid); 305 } 306 307 /* LINUX_CLONE_SETTLS: allocate a new TLS */ 308 if (led->clone_flags & LINUX_CLONE_SETTLS) { 309 if (linux_set_newtls(l, linux_get_newtls(l)) != 0) 310 printf("linux_userret: linux_set_tls failed"); 311 } 312 313 return; 314 } 315 316 void 317 linux_nptl_proc_exit(struct proc *p) 318 { 319 struct linux_emuldata *e = p->p_emuldata; 320 321 mutex_enter(proc_lock); 322 323 /* 324 * Check if we are a thread group leader victim of another 325 * thread doing exit_group(). If we are, change the exit code. 326 */ 327 if ((e->s->group_pid == p->p_pid) && 328 (e->s->flags & LINUX_LES_INEXITGROUP)) { 329 p->p_xstat = e->s->xstat; 330 } 331 332 /* 333 * Members of the thread groups others than the leader should 334 * exit quietely: no zombie stage, no signal. We do that by 335 * reparenting to init. init will collect us and nobody will 336 * notice what happened. 337 */ 338 #ifdef DEBUG_LINUX 339 printf("%s:%d e->s->group_pid = %d, p->p_pid = %d, flags = 0x%x\n", 340 __func__, __LINE__, e->s->group_pid, p->p_pid, e->s->flags); 341 #endif 342 if ((e->s->group_pid != p->p_pid) && 343 (e->clone_flags & LINUX_CLONE_THREAD)) { 344 proc_reparent(p, initproc); 345 cv_broadcast(&initproc->p_waitcv); 346 } 347 348 mutex_exit(proc_lock); 349 350 /* Emulate LINUX_CLONE_CHILD_CLEARTID */ 351 if (e->clear_tid != NULL) { 352 int error; 353 int null = 0; 354 struct linux_sys_futex_args cup; 355 register_t retval; 356 357 error = copyout(&null, e->clear_tid, sizeof(null)); 358 #ifdef DEBUG_LINUX 359 if (error != 0) 360 printf("%s: cannot clear TID\n", __func__); 361 #endif 362 363 SCARG(&cup, uaddr) = e->clear_tid; 364 SCARG(&cup, op) = LINUX_FUTEX_WAKE; 365 SCARG(&cup, val) = 0x7fffffff; /* Awake everyone */ 366 SCARG(&cup, timeout) = NULL; 367 SCARG(&cup, uaddr2) = NULL; 368 SCARG(&cup, val3) = 0; 369 if ((error = linux_sys_futex(curlwp, &cup, &retval)) != 0) 370 printf("%s: linux_sys_futex failed\n", __func__); 371 } 372 373 return; 374 } 375 376 void 377 linux_nptl_proc_fork(p, parent, luserret) 378 struct proc *p; 379 struct proc *parent; 380 void (*luserret)(void); 381 { 382 struct linux_emuldata *e = p->p_emuldata; 383 384 /* LINUX_CLONE_CHILD_CLEARTID: clear TID in child's memory on exit() */ 385 if (e->clone_flags & LINUX_CLONE_CHILD_CLEARTID) 386 e->clear_tid = e->child_tidptr; 387 388 /* LINUX_CLONE_PARENT_SETTID: set child's TID in parent's memory */ 389 if (e->clone_flags & LINUX_CLONE_PARENT_SETTID) { 390 if (copyout_proc(parent, &p->p_pid, 391 e->parent_tidptr, sizeof(p->p_pid)) != 0) 392 printf("%s: LINUX_CLONE_PARENT_SETTID " 393 "failed (e->parent_tidptr = %p, " 394 "parent->p_pid = %d, p->p_pid = %d)\n", 395 __func__, e->parent_tidptr, 396 parent->p_pid, p->p_pid); 397 } 398 399 /* 400 * CLONE_CHILD_SETTID and LINUX_CLONE_SETTLS require child's VM 401 * setup to be completed, we postpone them until userret time. 402 */ 403 if (e->clone_flags & 404 (LINUX_CLONE_CHILD_CLEARTID | LINUX_CLONE_SETTLS)) 405 p->p_userret = luserret; 406 407 return; 408 } 409 410 void 411 linux_nptl_proc_init(struct proc *p, struct proc *parent) 412 { 413 struct linux_emuldata *e = p->p_emuldata; 414 struct linux_emuldata *ep; 415 416 if ((parent != NULL) && (parent->p_emuldata != NULL)) { 417 ep = parent->p_emuldata; 418 419 e->parent_tidptr = ep->parent_tidptr; 420 e->child_tidptr = ep->child_tidptr; 421 e->clone_flags = ep->clone_flags; 422 } 423 424 return; 425 } 426 #endif /* LINUX_NPTL */ 427
Indexes created Tue Sep 23 14:10:03 GMT 2025