linux_exec.c revision 1.110.2.1
1 /* $NetBSD: linux_exec.c,v 1.110.2.1 2009/05/13 17:18:56 jym 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 1.110.2.1 2009/05/13 17:18:56 jym 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/syscallargs.h> 49 50 #include <sys/ptrace.h> /* For proc_reparent() */ 51 52 #include <uvm/uvm_extern.h> 53 54 #include <sys/cpu.h> 55 #include <machine/reg.h> 56 57 #include <compat/linux/common/linux_types.h> 58 #include <compat/linux/common/linux_signal.h> 59 #include <compat/linux/common/linux_util.h> 60 #include <compat/linux/common/linux_sched.h> 61 #include <compat/linux/common/linux_machdep.h> 62 #include <compat/linux/common/linux_exec.h> 63 #include <compat/linux/common/linux_futex.h> 64 #include <compat/linux/common/linux_ipc.h> 65 #include <compat/linux/common/linux_sem.h> 66 67 #include <compat/linux/linux_syscallargs.h> 68 #include <compat/linux/linux_syscall.h> 69 #include <compat/linux/common/linux_misc.h> 70 #include <compat/linux/common/linux_errno.h> 71 #include <compat/linux/common/linux_emuldata.h> 72 73 extern struct sysent linux_sysent[]; 74 extern const char * const linux_syscallnames[]; 75 extern char linux_sigcode[], linux_esigcode[]; 76 77 static void linux_e_proc_exec(struct proc *, struct exec_package *); 78 static void linux_e_proc_fork(struct proc *, struct proc *, int); 79 static void linux_e_proc_exit(struct proc *); 80 static void linux_e_proc_init(struct proc *, struct proc *, int); 81 82 #ifdef LINUX_NPTL 83 void linux_userret(void); 84 #endif 85 86 /* 87 * Emulation switch. 88 */ 89 90 struct uvm_object *emul_linux_object; 91 92 struct emul emul_linux = { 93 "linux", 94 "/emul/linux", 95 #ifndef __HAVE_MINIMAL_EMUL 96 0, 97 (const int *)native_to_linux_errno, 98 LINUX_SYS_syscall, 99 LINUX_SYS_NSYSENT, 100 #endif 101 linux_sysent, 102 linux_syscallnames, 103 linux_sendsig, 104 linux_trapsignal, 105 NULL, 106 linux_sigcode, 107 linux_esigcode, 108 &emul_linux_object, 109 linux_setregs, 110 linux_e_proc_exec, 111 linux_e_proc_fork, 112 linux_e_proc_exit, 113 NULL, 114 NULL, 115 #ifdef __HAVE_SYSCALL_INTERN 116 linux_syscall_intern, 117 #else 118 #error Implement __HAVE_SYSCALL_INTERN for this platform 119 #endif 120 NULL, 121 NULL, 122 123 uvm_default_mapaddr, 124 125 linux_usertrap, 126 NULL, /* e_sa */ 127 0, 128 NULL, /* e_startlwp */ 129 }; 130 131 static void 132 linux_e_proc_init(struct proc *p, struct proc *parent, int forkflags) 133 { 134 struct linux_emuldata *e = p->p_emuldata; 135 struct linux_emuldata_shared *s; 136 struct linux_emuldata *ep = NULL; 137 138 if (!e) { 139 /* allocate new Linux emuldata */ 140 e = malloc(sizeof(struct linux_emuldata), 141 M_EMULDATA, M_WAITOK); 142 } else { 143 mutex_enter(proc_lock); 144 e->s->refs--; 145 if (e->s->refs == 0) 146 free(e->s, M_EMULDATA); 147 mutex_exit(proc_lock); 148 } 149 150 memset(e, '\0', sizeof(struct linux_emuldata)); 151 152 e->proc = p; 153 e->robust_futexes = NULL; 154 155 if (parent) 156 ep = parent->p_emuldata; 157 158 if (forkflags & FORK_SHAREVM) { 159 mutex_enter(proc_lock); 160 #ifdef DIAGNOSTIC 161 if (ep == NULL) { 162 killproc(p, "FORK_SHAREVM while emuldata is NULL\n"); 163 mutex_exit(proc_lock); 164 free(e, M_EMULDATA); 165 return; 166 } 167 #endif 168 s = ep->s; 169 s->refs++; 170 } else { 171 struct vmspace *vm; 172 173 s = malloc(sizeof(struct linux_emuldata_shared), 174 M_EMULDATA, M_WAITOK); 175 s->refs = 1; 176 177 /* 178 * Set the process idea of the break to the real value. 179 * For fork, we use parent's vmspace since our's 180 * is not setup at the time of this call and is going 181 * to be copy of parent's anyway. For exec, just 182 * use our own vmspace. 183 */ 184 vm = (parent) ? parent->p_vmspace : p->p_vmspace; 185 s->p_break = (char *)vm->vm_daddr + ctob(vm->vm_dsize); 186 187 /* 188 * Linux threads are emulated as NetBSD processes (not lwp) 189 * We use native PID for Linux TID. The Linux TID is the 190 * PID of the first process in the group. It is stored 191 * here 192 */ 193 s->group_pid = p->p_pid; 194 195 /* 196 * Initialize the list of threads in the group 197 */ 198 LIST_INIT(&s->threads); 199 200 s->xstat = 0; 201 s->flags = 0; 202 mutex_enter(proc_lock); 203 } 204 205 e->s = s; 206 207 /* 208 * Add this thread in the group thread list 209 */ 210 LIST_INSERT_HEAD(&s->threads, e, threads); 211 212 #ifdef LINUX_NPTL 213 if (ep != NULL) { 214 e->parent_tidptr = ep->parent_tidptr; 215 e->child_tidptr = ep->child_tidptr; 216 e->clone_flags = ep->clone_flags; 217 } 218 #endif /* LINUX_NPTL */ 219 220 mutex_exit(proc_lock); 221 p->p_emuldata = e; 222 } 223 224 /* 225 * Allocate new per-process structures. Called when executing Linux 226 * process. We can reuse the old emuldata - if it's not null, 227 * the executed process is of same emulation as original forked one. 228 */ 229 static void 230 linux_e_proc_exec(struct proc *p, struct exec_package *epp) 231 { 232 233 /* exec, use our vmspace */ 234 linux_e_proc_init(p, NULL, 0); 235 } 236 237 /* 238 * Emulation per-process exit hook. 239 */ 240 static void 241 linux_e_proc_exit(struct proc *p) 242 { 243 struct linux_emuldata *e = p->p_emuldata; 244 245 #ifdef LINUX_NPTL 246 linux_nptl_proc_exit(p); 247 release_futexes(p); 248 #endif 249 250 /* Remove the thread for the group thread list */ 251 mutex_enter(proc_lock); 252 LIST_REMOVE(e, threads); 253 254 /* free Linux emuldata and set the pointer to null */ 255 e->s->refs--; 256 if (e->s->refs == 0) 257 free(e->s, M_EMULDATA); 258 p->p_emuldata = NULL; 259 mutex_exit(proc_lock); 260 free(e, M_EMULDATA); 261 } 262 263 /* 264 * Emulation fork hook. 265 */ 266 static void 267 linux_e_proc_fork(struct proc *p, struct proc *parent, int forkflags) 268 { 269 270 /* 271 * The new process might share some vmspace-related stuff 272 * with parent, depending on fork flags (CLONE_VM et.al). 273 * Force allocation of new base emuldata, and share the 274 * VM-related parts only if necessary. 275 */ 276 p->p_emuldata = NULL; 277 linux_e_proc_init(p, parent, forkflags); 278 279 #ifdef LINUX_NPTL 280 linux_nptl_proc_fork(p, parent, linux_userret); 281 #endif 282 283 return; 284 } 285 286 #ifdef LINUX_NPTL 287 void 288 linux_userret(void) 289 { 290 struct lwp *l = curlwp; 291 struct proc *p = l->l_proc; 292 struct linux_emuldata *led = p->p_emuldata; 293 int error; 294 295 /* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory */ 296 if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) { 297 if ((error = copyout(&l->l_proc->p_pid, 298 led->child_tidptr, sizeof(l->l_proc->p_pid))) != 0) 299 printf("linux_userret: LINUX_CLONE_CHILD_SETTID " 300 "failed (led->child_tidptr = %p, p->p_pid = %d)\n", 301 led->child_tidptr, p->p_pid); 302 } 303 304 /* LINUX_CLONE_SETTLS: allocate a new TLS */ 305 if (led->clone_flags & LINUX_CLONE_SETTLS) { 306 if (linux_set_newtls(l, linux_get_newtls(l)) != 0) 307 printf("linux_userret: linux_set_tls failed"); 308 } 309 310 return; 311 } 312 313 void 314 linux_nptl_proc_exit(struct proc *p) 315 { 316 struct linux_emuldata *e = p->p_emuldata; 317 318 mutex_enter(proc_lock); 319 320 /* 321 * Check if we are a thread group leader victim of another 322 * thread doing exit_group(). If we are, change the exit code. 323 */ 324 if ((e->s->group_pid == p->p_pid) && 325 (e->s->flags & LINUX_LES_INEXITGROUP)) { 326 p->p_xstat = e->s->xstat; 327 } 328 329 /* 330 * Members of the thread groups others than the leader should 331 * exit quietely: no zombie stage, no signal. We do that by 332 * reparenting to init. init will collect us and nobody will 333 * notice what happened. 334 */ 335 #ifdef DEBUG_LINUX 336 printf("%s:%d e->s->group_pid = %d, p->p_pid = %d, flags = 0x%x\n", 337 __func__, __LINE__, e->s->group_pid, p->p_pid, e->s->flags); 338 #endif 339 if ((e->s->group_pid != p->p_pid) && 340 (e->clone_flags & LINUX_CLONE_THREAD)) { 341 proc_reparent(p, initproc); 342 cv_broadcast(&initproc->p_waitcv); 343 } 344 345 mutex_exit(proc_lock); 346 347 /* Emulate LINUX_CLONE_CHILD_CLEARTID */ 348 if (e->clear_tid != NULL) { 349 int error; 350 int null = 0; 351 struct linux_sys_futex_args cup; 352 register_t retval; 353 354 error = copyout(&null, e->clear_tid, sizeof(null)); 355 #ifdef DEBUG_LINUX 356 if (error != 0) 357 printf("%s: cannot clear TID\n", __func__); 358 #endif 359 360 SCARG(&cup, uaddr) = e->clear_tid; 361 SCARG(&cup, op) = LINUX_FUTEX_WAKE; 362 SCARG(&cup, val) = 0x7fffffff; /* Awake everyone */ 363 SCARG(&cup, timeout) = NULL; 364 SCARG(&cup, uaddr2) = NULL; 365 SCARG(&cup, val3) = 0; 366 if ((error = linux_sys_futex(curlwp, &cup, &retval)) != 0) 367 printf("%s: linux_sys_futex failed\n", __func__); 368 } 369 370 return; 371 } 372 373 void 374 linux_nptl_proc_fork(struct proc *p, struct proc *parent, void (*luserret)(void)) 375 { 376 struct linux_emuldata *e = p->p_emuldata; 377 378 /* LINUX_CLONE_CHILD_CLEARTID: clear TID in child's memory on exit() */ 379 if (e->clone_flags & LINUX_CLONE_CHILD_CLEARTID) 380 e->clear_tid = e->child_tidptr; 381 382 /* LINUX_CLONE_PARENT_SETTID: set child's TID in parent's memory */ 383 if (e->clone_flags & LINUX_CLONE_PARENT_SETTID) { 384 if (copyout_proc(parent, &p->p_pid, 385 e->parent_tidptr, sizeof(p->p_pid)) != 0) 386 printf("%s: LINUX_CLONE_PARENT_SETTID " 387 "failed (e->parent_tidptr = %p, " 388 "parent->p_pid = %d, p->p_pid = %d)\n", 389 __func__, e->parent_tidptr, 390 parent->p_pid, p->p_pid); 391 } 392 393 /* 394 * CLONE_CHILD_SETTID and LINUX_CLONE_SETTLS require child's VM 395 * setup to be completed, we postpone them until userret time. 396 */ 397 if (e->clone_flags & 398 (LINUX_CLONE_CHILD_CLEARTID | LINUX_CLONE_SETTLS)) 399 p->p_userret = luserret; 400 401 return; 402 } 403 404 void 405 linux_nptl_proc_init(struct proc *p, struct proc *parent) 406 { 407 struct linux_emuldata *e = p->p_emuldata; 408 struct linux_emuldata *ep; 409 410 if ((parent != NULL) && (parent->p_emuldata != NULL)) { 411 ep = parent->p_emuldata; 412 413 e->parent_tidptr = ep->parent_tidptr; 414 e->child_tidptr = ep->child_tidptr; 415 e->clone_flags = ep->clone_flags; 416 } 417 418 return; 419 } 420 #endif /* LINUX_NPTL */ 421
Indexes created Wed Sep 24 05:09:52 GMT 2025