1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2004 Tim J. Robbins 5 * Copyright (c) 2002 Doug Rabson 6 * Copyright (c) 2000 Marcel Moolenaar 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer 14 * in this position and unchanged. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_compat.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/imgact.h> 39 #include <sys/ktr.h> 40 #include <sys/lock.h> 41 #include <sys/mutex.h> 42 #include <sys/proc.h> 43 #include <sys/ptrace.h> 44 #include <sys/racct.h> 45 #include <sys/sched.h> 46 #include <sys/syscallsubr.h> 47 #include <sys/sx.h> 48 #include <sys/umtx.h> 49 #include <sys/unistd.h> 50 #include <sys/wait.h> 51 52 #include <vm/vm.h> 53 #include <vm/pmap.h> 54 #include <vm/vm_map.h> 55 56 #ifdef COMPAT_LINUX32 57 #include <machine/../linux32/linux.h> 58 #include <machine/../linux32/linux32_proto.h> 59 #else 60 #include <machine/../linux/linux.h> 61 #include <machine/../linux/linux_proto.h> 62 #endif 63 #include <compat/linux/linux_emul.h> 64 #include <compat/linux/linux_futex.h> 65 #include <compat/linux/linux_misc.h> 66 #include <compat/linux/linux_util.h> 67 68 #ifdef LINUX_LEGACY_SYSCALLS 69 int 70 linux_fork(struct thread *td, struct linux_fork_args *args) 71 { 72 struct fork_req fr; 73 int error; 74 struct proc *p2; 75 struct thread *td2; 76 77 bzero(&fr, sizeof(fr)); 78 fr.fr_flags = RFFDG | RFPROC | RFSTOPPED; 79 fr.fr_procp = &p2; 80 if ((error = fork1(td, &fr)) != 0) 81 return (error); 82 83 td2 = FIRST_THREAD_IN_PROC(p2); 84 85 linux_proc_init(td, td2, 0); 86 87 td->td_retval[0] = p2->p_pid; 88 89 /* 90 * Make this runnable after we are finished with it. 91 */ 92 thread_lock(td2); 93 TD_SET_CAN_RUN(td2); 94 sched_add(td2, SRQ_BORING); 95 thread_unlock(td2); 96 97 return (0); 98 } 99 100 int 101 linux_vfork(struct thread *td, struct linux_vfork_args *args) 102 { 103 struct fork_req fr; 104 int error; 105 struct proc *p2; 106 struct thread *td2; 107 108 bzero(&fr, sizeof(fr)); 109 fr.fr_flags = RFFDG | RFPROC | RFMEM | RFPPWAIT | RFSTOPPED; 110 fr.fr_procp = &p2; 111 if ((error = fork1(td, &fr)) != 0) 112 return (error); 113 114 td2 = FIRST_THREAD_IN_PROC(p2); 115 116 linux_proc_init(td, td2, 0); 117 118 td->td_retval[0] = p2->p_pid; 119 120 /* 121 * Make this runnable after we are finished with it. 122 */ 123 thread_lock(td2); 124 TD_SET_CAN_RUN(td2); 125 sched_add(td2, SRQ_BORING); 126 thread_unlock(td2); 127 128 return (0); 129 } 130 #endif 131 132 static int 133 linux_clone_proc(struct thread *td, struct linux_clone_args *args) 134 { 135 struct fork_req fr; 136 int error, ff = RFPROC | RFSTOPPED; 137 struct proc *p2; 138 struct thread *td2; 139 int exit_signal; 140 struct linux_emuldata *em; 141 142 exit_signal = args->flags & 0x000000ff; 143 if (LINUX_SIG_VALID(exit_signal)) { 144 exit_signal = linux_to_bsd_signal(exit_signal); 145 } else if (exit_signal != 0) 146 return (EINVAL); 147 148 if (args->flags & LINUX_CLONE_VM) 149 ff |= RFMEM; 150 if (args->flags & LINUX_CLONE_SIGHAND) 151 ff |= RFSIGSHARE; 152 /* 153 * XXX: In Linux, sharing of fs info (chroot/cwd/umask) 154 * and open files is independent. In FreeBSD, its in one 155 * structure but in reality it does not cause any problems 156 * because both of these flags are usually set together. 157 */ 158 if (!(args->flags & (LINUX_CLONE_FILES | LINUX_CLONE_FS))) 159 ff |= RFFDG; 160 161 if (args->flags & LINUX_CLONE_PARENT_SETTID) 162 if (args->parent_tidptr == NULL) 163 return (EINVAL); 164 165 if (args->flags & LINUX_CLONE_VFORK) 166 ff |= RFPPWAIT; 167 168 bzero(&fr, sizeof(fr)); 169 fr.fr_flags = ff; 170 fr.fr_procp = &p2; 171 error = fork1(td, &fr); 172 if (error) 173 return (error); 174 175 td2 = FIRST_THREAD_IN_PROC(p2); 176 177 /* create the emuldata */ 178 linux_proc_init(td, td2, args->flags); 179 180 em = em_find(td2); 181 KASSERT(em != NULL, ("clone_proc: emuldata not found.\n")); 182 183 if (args->flags & LINUX_CLONE_CHILD_SETTID) 184 em->child_set_tid = args->child_tidptr; 185 else 186 em->child_set_tid = NULL; 187 188 if (args->flags & LINUX_CLONE_CHILD_CLEARTID) 189 em->child_clear_tid = args->child_tidptr; 190 else 191 em->child_clear_tid = NULL; 192 193 if (args->flags & LINUX_CLONE_PARENT_SETTID) { 194 error = copyout(&p2->p_pid, args->parent_tidptr, 195 sizeof(p2->p_pid)); 196 if (error) 197 linux_msg(td, "copyout p_pid failed!"); 198 } 199 200 PROC_LOCK(p2); 201 p2->p_sigparent = exit_signal; 202 PROC_UNLOCK(p2); 203 /* 204 * In a case of stack = NULL, we are supposed to COW calling process 205 * stack. This is what normal fork() does, so we just keep tf_rsp arg 206 * intact. 207 */ 208 linux_set_upcall_kse(td2, PTROUT(args->stack)); 209 210 if (args->flags & LINUX_CLONE_SETTLS) 211 linux_set_cloned_tls(td2, args->tls); 212 213 /* 214 * If CLONE_PARENT is set, then the parent of the new process will be 215 * the same as that of the calling process. 216 */ 217 if (args->flags & LINUX_CLONE_PARENT) { 218 sx_xlock(&proctree_lock); 219 PROC_LOCK(p2); 220 proc_reparent(p2, td->td_proc->p_pptr, true); 221 PROC_UNLOCK(p2); 222 sx_xunlock(&proctree_lock); 223 } 224 225 /* 226 * Make this runnable after we are finished with it. 227 */ 228 thread_lock(td2); 229 TD_SET_CAN_RUN(td2); 230 sched_add(td2, SRQ_BORING); 231 thread_unlock(td2); 232 233 td->td_retval[0] = p2->p_pid; 234 235 return (0); 236 } 237 238 static int 239 linux_clone_thread(struct thread *td, struct linux_clone_args *args) 240 { 241 struct linux_emuldata *em; 242 struct thread *newtd; 243 struct proc *p; 244 int error; 245 246 LINUX_CTR4(clone_thread, "thread(%d) flags %x ptid %p ctid %p", 247 td->td_tid, (unsigned)args->flags, 248 args->parent_tidptr, args->child_tidptr); 249 250 if (args->flags & LINUX_CLONE_PARENT_SETTID) 251 if (args->parent_tidptr == NULL) 252 return (EINVAL); 253 254 /* Threads should be created with own stack */ 255 if (args->stack == NULL) 256 return (EINVAL); 257 258 p = td->td_proc; 259 260 #ifdef RACCT 261 if (racct_enable) { 262 PROC_LOCK(p); 263 error = racct_add(p, RACCT_NTHR, 1); 264 PROC_UNLOCK(p); 265 if (error != 0) 266 return (EPROCLIM); 267 } 268 #endif 269 270 /* Initialize our td */ 271 error = kern_thr_alloc(p, 0, &newtd); 272 if (error) 273 goto fail; 274 275 cpu_copy_thread(newtd, td); 276 277 bzero(&newtd->td_startzero, 278 __rangeof(struct thread, td_startzero, td_endzero)); 279 bcopy(&td->td_startcopy, &newtd->td_startcopy, 280 __rangeof(struct thread, td_startcopy, td_endcopy)); 281 282 newtd->td_proc = p; 283 thread_cow_get(newtd, td); 284 285 /* create the emuldata */ 286 linux_proc_init(td, newtd, args->flags); 287 288 em = em_find(newtd); 289 KASSERT(em != NULL, ("clone_thread: emuldata not found.\n")); 290 291 if (args->flags & LINUX_CLONE_SETTLS) 292 linux_set_cloned_tls(newtd, args->tls); 293 294 if (args->flags & LINUX_CLONE_CHILD_SETTID) 295 em->child_set_tid = args->child_tidptr; 296 else 297 em->child_set_tid = NULL; 298 299 if (args->flags & LINUX_CLONE_CHILD_CLEARTID) 300 em->child_clear_tid = args->child_tidptr; 301 else 302 em->child_clear_tid = NULL; 303 304 cpu_thread_clean(newtd); 305 306 linux_set_upcall_kse(newtd, PTROUT(args->stack)); 307 308 PROC_LOCK(p); 309 p->p_flag |= P_HADTHREADS; 310 bcopy(p->p_comm, newtd->td_name, sizeof(newtd->td_name)); 311 312 if (args->flags & LINUX_CLONE_PARENT) 313 thread_link(newtd, p->p_pptr); 314 else 315 thread_link(newtd, p); 316 317 thread_lock(td); 318 /* let the scheduler know about these things. */ 319 sched_fork_thread(td, newtd); 320 thread_unlock(td); 321 if (P_SHOULDSTOP(p)) 322 newtd->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 323 324 if (p->p_ptevents & PTRACE_LWP) 325 newtd->td_dbgflags |= TDB_BORN; 326 PROC_UNLOCK(p); 327 328 tidhash_add(newtd); 329 330 LINUX_CTR2(clone_thread, "thread(%d) successful clone to %d", 331 td->td_tid, newtd->td_tid); 332 333 if (args->flags & LINUX_CLONE_PARENT_SETTID) { 334 error = copyout(&newtd->td_tid, args->parent_tidptr, 335 sizeof(newtd->td_tid)); 336 if (error) 337 linux_msg(td, "clone_thread: copyout td_tid failed!"); 338 } 339 340 /* 341 * Make this runnable after we are finished with it. 342 */ 343 thread_lock(newtd); 344 TD_SET_CAN_RUN(newtd); 345 sched_add(newtd, SRQ_BORING); 346 thread_unlock(newtd); 347 348 td->td_retval[0] = newtd->td_tid; 349 350 return (0); 351 352 fail: 353 #ifdef RACCT 354 if (racct_enable) { 355 PROC_LOCK(p); 356 racct_sub(p, RACCT_NTHR, 1); 357 PROC_UNLOCK(p); 358 } 359 #endif 360 return (error); 361 } 362 363 int 364 linux_clone(struct thread *td, struct linux_clone_args *args) 365 { 366 367 if (args->flags & LINUX_CLONE_THREAD) 368 return (linux_clone_thread(td, args)); 369 else 370 return (linux_clone_proc(td, args)); 371 } 372 373 int 374 linux_exit(struct thread *td, struct linux_exit_args *args) 375 { 376 struct linux_emuldata *em; 377 378 em = em_find(td); 379 KASSERT(em != NULL, ("exit: emuldata not found.\n")); 380 381 LINUX_CTR2(exit, "thread(%d) (%d)", em->em_tid, args->rval); 382 383 umtx_thread_exit(td); 384 385 linux_thread_detach(td); 386 387 /* 388 * XXX. When the last two threads of a process 389 * exit via pthread_exit() try thr_exit() first. 390 */ 391 kern_thr_exit(td); 392 exit1(td, args->rval, 0); 393 /* NOTREACHED */ 394 } 395 396 int 397 linux_set_tid_address(struct thread *td, struct linux_set_tid_address_args *args) 398 { 399 struct linux_emuldata *em; 400 401 em = em_find(td); 402 KASSERT(em != NULL, ("set_tid_address: emuldata not found.\n")); 403 404 em->child_clear_tid = args->tidptr; 405 406 td->td_retval[0] = em->em_tid; 407 408 LINUX_CTR3(set_tid_address, "tidptr(%d) %p, returns %d", 409 em->em_tid, args->tidptr, td->td_retval[0]); 410 411 return (0); 412 } 413 414 void 415 linux_thread_detach(struct thread *td) 416 { 417 struct linux_sys_futex_args cup; 418 struct linux_emuldata *em; 419 int *child_clear_tid; 420 int error; 421 422 em = em_find(td); 423 KASSERT(em != NULL, ("thread_detach: emuldata not found.\n")); 424 425 LINUX_CTR1(thread_detach, "thread(%d)", em->em_tid); 426 427 release_futexes(td, em); 428 429 child_clear_tid = em->child_clear_tid; 430 431 if (child_clear_tid != NULL) { 432 433 LINUX_CTR2(thread_detach, "thread(%d) %p", 434 em->em_tid, child_clear_tid); 435 436 error = suword32(child_clear_tid, 0); 437 if (error != 0) 438 return; 439 440 cup.uaddr = child_clear_tid; 441 cup.op = LINUX_FUTEX_WAKE; 442 cup.val = 1; /* wake one */ 443 cup.timeout = NULL; 444 cup.uaddr2 = NULL; 445 cup.val3 = 0; 446 error = linux_sys_futex(td, &cup); 447 /* 448 * this cannot happen at the moment and if this happens it 449 * probably means there is a user space bug 450 */ 451 if (error != 0) 452 linux_msg(td, "futex stuff in thread_detach failed."); 453 } 454 } 455