1 /* $NetBSD: linux_file.c,v 1.96 2008/04/28 20:23:43 martin Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 1998, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Frank van der Linden and Eric Haszlakiewicz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Functions in multiarch: 34 * linux_sys_llseek : linux_llseek.c 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: linux_file.c,v 1.96 2008/04/28 20:23:43 martin Exp $"); 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/namei.h> 43 #include <sys/proc.h> 44 #include <sys/file.h> 45 #include <sys/stat.h> 46 #include <sys/filedesc.h> 47 #include <sys/ioctl.h> 48 #include <sys/kernel.h> 49 #include <sys/mount.h> 50 #include <sys/malloc.h> 51 #include <sys/namei.h> 52 #include <sys/vnode.h> 53 #include <sys/tty.h> 54 #include <sys/socketvar.h> 55 #include <sys/conf.h> 56 #include <sys/pipe.h> 57 58 #include <sys/syscallargs.h> 59 #include <sys/vfs_syscalls.h> 60 61 #include <compat/linux/common/linux_types.h> 62 #include <compat/linux/common/linux_signal.h> 63 #include <compat/linux/common/linux_fcntl.h> 64 #include <compat/linux/common/linux_util.h> 65 #include <compat/linux/common/linux_machdep.h> 66 #include <compat/linux/common/linux_ipc.h> 67 #include <compat/linux/common/linux_sem.h> 68 69 #include <compat/linux/linux_syscallargs.h> 70 71 static int linux_to_bsd_ioflags(int); 72 static int bsd_to_linux_ioflags(int); 73 #ifndef __amd64__ 74 static void bsd_to_linux_stat(struct stat *, struct linux_stat *); 75 #endif 76 77 conv_linux_flock(linux, flock) 78 79 /* 80 * Some file-related calls are handled here. The usual flag conversion 81 * an structure conversion is done, and alternate emul path searching. 82 */ 83 84 /* 85 * The next two functions convert between the Linux and NetBSD values 86 * of the flags used in open(2) and fcntl(2). 87 */ 88 static int 89 linux_to_bsd_ioflags(int lflags) 90 { 91 int res = 0; 92 93 res |= cvtto_bsd_mask(lflags, LINUX_O_WRONLY, O_WRONLY); 94 res |= cvtto_bsd_mask(lflags, LINUX_O_RDONLY, O_RDONLY); 95 res |= cvtto_bsd_mask(lflags, LINUX_O_RDWR, O_RDWR); 96 res |= cvtto_bsd_mask(lflags, LINUX_O_CREAT, O_CREAT); 97 res |= cvtto_bsd_mask(lflags, LINUX_O_EXCL, O_EXCL); 98 res |= cvtto_bsd_mask(lflags, LINUX_O_NOCTTY, O_NOCTTY); 99 res |= cvtto_bsd_mask(lflags, LINUX_O_TRUNC, O_TRUNC); 100 res |= cvtto_bsd_mask(lflags, LINUX_O_NDELAY, O_NDELAY); 101 res |= cvtto_bsd_mask(lflags, LINUX_O_SYNC, O_FSYNC); 102 res |= cvtto_bsd_mask(lflags, LINUX_FASYNC, O_ASYNC); 103 res |= cvtto_bsd_mask(lflags, LINUX_O_APPEND, O_APPEND); 104 105 return res; 106 } 107 108 static int 109 bsd_to_linux_ioflags(int bflags) 110 { 111 int res = 0; 112 113 res |= cvtto_linux_mask(bflags, O_WRONLY, LINUX_O_WRONLY); 114 res |= cvtto_linux_mask(bflags, O_RDONLY, LINUX_O_RDONLY); 115 res |= cvtto_linux_mask(bflags, O_RDWR, LINUX_O_RDWR); 116 res |= cvtto_linux_mask(bflags, O_CREAT, LINUX_O_CREAT); 117 res |= cvtto_linux_mask(bflags, O_EXCL, LINUX_O_EXCL); 118 res |= cvtto_linux_mask(bflags, O_NOCTTY, LINUX_O_NOCTTY); 119 res |= cvtto_linux_mask(bflags, O_TRUNC, LINUX_O_TRUNC); 120 res |= cvtto_linux_mask(bflags, O_NDELAY, LINUX_O_NDELAY); 121 res |= cvtto_linux_mask(bflags, O_FSYNC, LINUX_O_SYNC); 122 res |= cvtto_linux_mask(bflags, O_ASYNC, LINUX_FASYNC); 123 res |= cvtto_linux_mask(bflags, O_APPEND, LINUX_O_APPEND); 124 125 return res; 126 } 127 128 /* 129 * creat(2) is an obsolete function, but it's present as a Linux 130 * system call, so let's deal with it. 131 * 132 * Note: On the Alpha this doesn't really exist in Linux, but it's defined 133 * in syscalls.master anyway so this doesn't have to be special cased. 134 * 135 * Just call open(2) with the TRUNC, CREAT and WRONLY flags. 136 */ 137 int 138 linux_sys_creat(struct lwp *l, const struct linux_sys_creat_args *uap, register_t *retval) 139 { 140 /* { 141 syscallarg(const char *) path; 142 syscallarg(int) mode; 143 } */ 144 struct sys_open_args oa; 145 146 SCARG(&oa, path) = SCARG(uap, path); 147 SCARG(&oa, flags) = O_CREAT | O_TRUNC | O_WRONLY; 148 SCARG(&oa, mode) = SCARG(uap, mode); 149 150 return sys_open(l, &oa, retval); 151 } 152 153 /* 154 * open(2). Take care of the different flag values, and let the 155 * NetBSD syscall do the real work. See if this operation 156 * gives the current process a controlling terminal. 157 * (XXX is this necessary?) 158 */ 159 int 160 linux_sys_open(struct lwp *l, const struct linux_sys_open_args *uap, register_t *retval) 161 { 162 /* { 163 syscallarg(const char *) path; 164 syscallarg(int) flags; 165 syscallarg(int) mode; 166 } */ 167 struct proc *p = l->l_proc; 168 int error, fl; 169 struct sys_open_args boa; 170 171 fl = linux_to_bsd_ioflags(SCARG(uap, flags)); 172 173 SCARG(&boa, path) = SCARG(uap, path); 174 SCARG(&boa, flags) = fl; 175 SCARG(&boa, mode) = SCARG(uap, mode); 176 177 if ((error = sys_open(l, &boa, retval))) 178 return error; 179 180 /* 181 * this bit from sunos_misc.c (and svr4_fcntl.c). 182 * If we are a session leader, and we don't have a controlling 183 * terminal yet, and the O_NOCTTY flag is not set, try to make 184 * this the controlling terminal. 185 */ 186 if (!(fl & O_NOCTTY) && SESS_LEADER(p) && !(p->p_lflag & PL_CONTROLT)) { 187 file_t *fp; 188 189 fp = fd_getfile(*retval); 190 191 /* ignore any error, just give it a try */ 192 if (fp != NULL) { 193 if (fp->f_type == DTYPE_VNODE) { 194 (fp->f_ops->fo_ioctl) (fp, TIOCSCTTY, NULL); 195 } 196 fd_putfile(*retval); 197 } 198 } 199 return 0; 200 } 201 202 /* 203 * Most actions in the fcntl() call are straightforward; simply 204 * pass control to the NetBSD system call. A few commands need 205 * conversions after the actual system call has done its work, 206 * because the flag values and lock structure are different. 207 */ 208 int 209 linux_sys_fcntl(struct lwp *l, const struct linux_sys_fcntl_args *uap, register_t *retval) 210 { 211 /* { 212 syscallarg(int) fd; 213 syscallarg(int) cmd; 214 syscallarg(void *) arg; 215 } */ 216 struct proc *p = l->l_proc; 217 int fd, cmd, error; 218 u_long val; 219 void *arg; 220 struct sys_fcntl_args fca; 221 file_t *fp; 222 struct vnode *vp; 223 struct vattr va; 224 long pgid; 225 struct pgrp *pgrp; 226 struct tty *tp; 227 228 fd = SCARG(uap, fd); 229 cmd = SCARG(uap, cmd); 230 arg = SCARG(uap, arg); 231 232 switch (cmd) { 233 234 case LINUX_F_DUPFD: 235 cmd = F_DUPFD; 236 break; 237 238 case LINUX_F_GETFD: 239 cmd = F_GETFD; 240 break; 241 242 case LINUX_F_SETFD: 243 cmd = F_SETFD; 244 break; 245 246 case LINUX_F_GETFL: 247 SCARG(&fca, fd) = fd; 248 SCARG(&fca, cmd) = F_GETFL; 249 SCARG(&fca, arg) = arg; 250 if ((error = sys_fcntl(l, &fca, retval))) 251 return error; 252 retval[0] = bsd_to_linux_ioflags(retval[0]); 253 return 0; 254 255 case LINUX_F_SETFL: { 256 file_t *fp1 = NULL; 257 258 val = linux_to_bsd_ioflags((unsigned long)SCARG(uap, arg)); 259 /* 260 * Linux seems to have same semantics for sending SIGIO to the 261 * read side of socket, but slightly different semantics 262 * for SIGIO to the write side. Rather than sending the SIGIO 263 * every time it's possible to write (directly) more data, it 264 * only sends SIGIO if last write(2) failed due to insufficient 265 * memory to hold the data. This is compatible enough 266 * with NetBSD semantics to not do anything about the 267 * difference. 268 * 269 * Linux does NOT send SIGIO for pipes. Deal with socketpair 270 * ones and DTYPE_PIPE ones. For these, we don't set 271 * the underlying flags (we don't pass O_ASYNC flag down 272 * to sys_fcntl()), but set the FASYNC flag for file descriptor, 273 * so that F_GETFL would report the ASYNC i/o is on. 274 */ 275 if (val & O_ASYNC) { 276 if (((fp1 = fd_getfile(fd)) == NULL)) 277 return (EBADF); 278 if (((fp1->f_type == DTYPE_SOCKET) && fp1->f_data 279 && ((struct socket *)fp1->f_data)->so_state & SS_ISAPIPE) 280 || (fp1->f_type == DTYPE_PIPE)) 281 val &= ~O_ASYNC; 282 else { 283 /* not a pipe, do not modify anything */ 284 fd_putfile(fd); 285 fp1 = NULL; 286 } 287 } 288 289 SCARG(&fca, fd) = fd; 290 SCARG(&fca, cmd) = F_SETFL; 291 SCARG(&fca, arg) = (void *) val; 292 293 error = sys_fcntl(l, &fca, retval); 294 295 /* Now set the FASYNC flag for pipes */ 296 if (fp1) { 297 if (!error) { 298 mutex_enter(&fp1->f_lock); 299 fp1->f_flag |= FASYNC; 300 mutex_exit(&fp1->f_lock); 301 } 302 fd_putfile(fd); 303 } 304 305 return (error); 306 } 307 308 case LINUX_F_GETLK: 309 do_linux_getlk(fd, cmd, arg, linux, flock); 310 311 case LINUX_F_SETLK: 312 case LINUX_F_SETLKW: 313 do_linux_setlk(fd, cmd, arg, linux, flock, LINUX_F_SETLK); 314 315 case LINUX_F_SETOWN: 316 case LINUX_F_GETOWN: 317 /* 318 * We need to route fcntl() for tty descriptors around normal 319 * fcntl(), since NetBSD tty TIOC{G,S}PGRP semantics is too 320 * restrictive for Linux F_{G,S}ETOWN. For non-tty descriptors, 321 * this is not a problem. 322 */ 323 if ((fp = fd_getfile(fd)) == NULL) 324 return EBADF; 325 326 /* Check it's a character device vnode */ 327 if (fp->f_type != DTYPE_VNODE 328 || (vp = (struct vnode *)fp->f_data) == NULL 329 || vp->v_type != VCHR) { 330 fd_putfile(fd); 331 332 not_tty: 333 /* Not a tty, proceed with common fcntl() */ 334 cmd = cmd == LINUX_F_SETOWN ? F_SETOWN : F_GETOWN; 335 break; 336 } 337 338 error = VOP_GETATTR(vp, &va, l->l_cred); 339 340 fd_putfile(fd); 341 342 if (error) 343 return error; 344 345 if ((tp = cdev_tty(va.va_rdev)) == NULL) 346 goto not_tty; 347 348 /* set tty pg_id appropriately */ 349 mutex_enter(proc_lock); 350 if (cmd == LINUX_F_GETOWN) { 351 retval[0] = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PGID; 352 mutex_exit(proc_lock); 353 return 0; 354 } 355 if ((long)arg <= 0) { 356 pgid = -(long)arg; 357 } else { 358 struct proc *p1 = p_find((long)arg, PFIND_LOCKED | PFIND_UNLOCK_FAIL); 359 if (p1 == NULL) 360 return (ESRCH); 361 pgid = (long)p1->p_pgrp->pg_id; 362 } 363 pgrp = pg_find(pgid, PFIND_LOCKED); 364 if (pgrp == NULL || pgrp->pg_session != p->p_session) { 365 mutex_exit(proc_lock); 366 return EPERM; 367 } 368 tp->t_pgrp = pgrp; 369 mutex_exit(proc_lock); 370 return 0; 371 372 default: 373 return EOPNOTSUPP; 374 } 375 376 SCARG(&fca, fd) = fd; 377 SCARG(&fca, cmd) = cmd; 378 SCARG(&fca, arg) = arg; 379 380 return sys_fcntl(l, &fca, retval); 381 } 382 383 #if !defined(__amd64__) 384 /* 385 * Convert a NetBSD stat structure to a Linux stat structure. 386 * Only the order of the fields and the padding in the structure 387 * is different. linux_fakedev is a machine-dependent function 388 * which optionally converts device driver major/minor numbers 389 * (XXX horrible, but what can you do against code that compares 390 * things against constant major device numbers? sigh) 391 */ 392 static void 393 bsd_to_linux_stat(struct stat *bsp, struct linux_stat *lsp) 394 { 395 396 lsp->lst_dev = linux_fakedev(bsp->st_dev, 0); 397 lsp->lst_ino = bsp->st_ino; 398 lsp->lst_mode = (linux_mode_t)bsp->st_mode; 399 if (bsp->st_nlink >= (1 << 15)) 400 lsp->lst_nlink = (1 << 15) - 1; 401 else 402 lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink; 403 lsp->lst_uid = bsp->st_uid; 404 lsp->lst_gid = bsp->st_gid; 405 lsp->lst_rdev = linux_fakedev(bsp->st_rdev, 1); 406 lsp->lst_size = bsp->st_size; 407 lsp->lst_blksize = bsp->st_blksize; 408 lsp->lst_blocks = bsp->st_blocks; 409 lsp->lst_atime = bsp->st_atime; 410 lsp->lst_mtime = bsp->st_mtime; 411 lsp->lst_ctime = bsp->st_ctime; 412 #ifdef LINUX_STAT_HAS_NSEC 413 lsp->lst_atime_nsec = bsp->st_atimensec; 414 lsp->lst_mtime_nsec = bsp->st_mtimensec; 415 lsp->lst_ctime_nsec = bsp->st_ctimensec; 416 #endif 417 } 418 419 /* 420 * The stat functions below are plain sailing. stat and lstat are handled 421 * by one function to avoid code duplication. 422 */ 423 int 424 linux_sys_fstat(struct lwp *l, const struct linux_sys_fstat_args *uap, register_t *retval) 425 { 426 /* { 427 syscallarg(int) fd; 428 syscallarg(linux_stat *) sp; 429 } */ 430 struct linux_stat tmplst; 431 struct stat tmpst; 432 int error; 433 434 error = do_sys_fstat(SCARG(uap, fd), &tmpst); 435 if (error != 0) 436 return error; 437 bsd_to_linux_stat(&tmpst, &tmplst); 438 439 return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); 440 } 441 442 static int 443 linux_stat1(const struct linux_sys_stat_args *uap, register_t *retval, int flags) 444 { 445 struct linux_stat tmplst; 446 struct stat tmpst; 447 int error; 448 449 error = do_sys_stat(SCARG(uap, path), flags, &tmpst); 450 if (error != 0) 451 return error; 452 453 bsd_to_linux_stat(&tmpst, &tmplst); 454 455 return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); 456 } 457 458 int 459 linux_sys_stat(struct lwp *l, const struct linux_sys_stat_args *uap, register_t *retval) 460 { 461 /* { 462 syscallarg(const char *) path; 463 syscallarg(struct linux_stat *) sp; 464 } */ 465 466 return linux_stat1(uap, retval, FOLLOW); 467 } 468 469 /* Note: this is "newlstat" in the Linux sources */ 470 /* (we don't bother with the old lstat currently) */ 471 int 472 linux_sys_lstat(struct lwp *l, const struct linux_sys_lstat_args *uap, register_t *retval) 473 { 474 /* { 475 syscallarg(const char *) path; 476 syscallarg(struct linux_stat *) sp; 477 } */ 478 479 return linux_stat1((const void *)uap, retval, NOFOLLOW); 480 } 481 #endif /* !__amd64__ */ 482 483 /* 484 * The following syscalls are mostly here because of the alternate path check. 485 */ 486 int 487 linux_sys_unlink(struct lwp *l, const struct linux_sys_unlink_args *uap, register_t *retval) 488 { 489 /* { 490 syscallarg(const char *) path; 491 } */ 492 int error; 493 struct nameidata nd; 494 495 error = sys_unlink(l, (const void *)uap, retval); 496 if (error != EPERM) 497 return (error); 498 499 /* 500 * Linux returns EISDIR if unlink(2) is called on a directory. 501 * We return EPERM in such cases. To emulate correct behaviour, 502 * check if the path points to directory and return EISDIR if this 503 * is the case. 504 */ 505 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | TRYEMULROOT, UIO_USERSPACE, 506 SCARG(uap, path)); 507 if (namei(&nd) == 0) { 508 struct stat sb; 509 510 if (vn_stat(nd.ni_vp, &sb) == 0 511 && S_ISDIR(sb.st_mode)) 512 error = EISDIR; 513 514 vput(nd.ni_vp); 515 } 516 517 return (error); 518 } 519 520 int 521 linux_sys_mknod(struct lwp *l, const struct linux_sys_mknod_args *uap, register_t *retval) 522 { 523 /* { 524 syscallarg(const char *) path; 525 syscallarg(int) mode; 526 syscallarg(int) dev; 527 } */ 528 529 /* 530 * BSD handles FIFOs separately 531 */ 532 if (S_ISFIFO(SCARG(uap, mode))) { 533 struct sys_mkfifo_args bma; 534 535 SCARG(&bma, path) = SCARG(uap, path); 536 SCARG(&bma, mode) = SCARG(uap, mode); 537 return sys_mkfifo(l, &bma, retval); 538 } else { 539 struct sys_mknod_args bma; 540 541 SCARG(&bma, path) = SCARG(uap, path); 542 SCARG(&bma, mode) = SCARG(uap, mode); 543 /* 544 * Linux device numbers uses 8 bits for minor and 8 bits 545 * for major. Due to how we map our major and minor, 546 * this just fits into our dev_t. Just mask off the 547 * upper 16bit to remove any random junk. 548 */ 549 SCARG(&bma, dev) = SCARG(uap, dev) & 0xffff; 550 return sys_mknod(l, &bma, retval); 551 } 552 } 553 554 /* 555 * This is just fsync() for now (just as it is in the Linux kernel) 556 * Note: this is not implemented under Linux on Alpha and Arm 557 * but should still be defined in our syscalls.master. 558 * (syscall #148 on the arm) 559 */ 560 int 561 linux_sys_fdatasync(struct lwp *l, const struct linux_sys_fdatasync_args *uap, register_t *retval) 562 { 563 /* { 564 syscallarg(int) fd; 565 } */ 566 567 return sys_fsync(l, (const void *)uap, retval); 568 } 569 570 /* 571 * pread(2). 572 */ 573 int 574 linux_sys_pread(struct lwp *l, const struct linux_sys_pread_args *uap, register_t *retval) 575 { 576 /* { 577 syscallarg(int) fd; 578 syscallarg(void *) buf; 579 syscallarg(size_t) nbyte; 580 syscallarg(linux_off_t) offset; 581 } */ 582 struct sys_pread_args pra; 583 584 SCARG(&pra, fd) = SCARG(uap, fd); 585 SCARG(&pra, buf) = SCARG(uap, buf); 586 SCARG(&pra, nbyte) = SCARG(uap, nbyte); 587 SCARG(&pra, offset) = SCARG(uap, offset); 588 589 return sys_pread(l, &pra, retval); 590 } 591 592 /* 593 * pwrite(2). 594 */ 595 int 596 linux_sys_pwrite(struct lwp *l, const struct linux_sys_pwrite_args *uap, register_t *retval) 597 { 598 /* { 599 syscallarg(int) fd; 600 syscallarg(void *) buf; 601 syscallarg(size_t) nbyte; 602 syscallarg(linux_off_t) offset; 603 } */ 604 struct sys_pwrite_args pra; 605 606 SCARG(&pra, fd) = SCARG(uap, fd); 607 SCARG(&pra, buf) = SCARG(uap, buf); 608 SCARG(&pra, nbyte) = SCARG(uap, nbyte); 609 SCARG(&pra, offset) = SCARG(uap, offset); 610 611 return sys_pwrite(l, &pra, retval); 612 } 613 614 #define LINUX_NOT_SUPPORTED(fun) \ 615 int \ 616 fun(struct lwp *l, const struct fun##_args *uap, register_t *retval) \ 617 { \ 618 return EOPNOTSUPP; \ 619 } 620 621 LINUX_NOT_SUPPORTED(linux_sys_setxattr) 622 LINUX_NOT_SUPPORTED(linux_sys_lsetxattr) 623 LINUX_NOT_SUPPORTED(linux_sys_fsetxattr) 624 625 LINUX_NOT_SUPPORTED(linux_sys_getxattr) 626 LINUX_NOT_SUPPORTED(linux_sys_lgetxattr) 627 LINUX_NOT_SUPPORTED(linux_sys_fgetxattr) 628 629 LINUX_NOT_SUPPORTED(linux_sys_listxattr) 630 LINUX_NOT_SUPPORTED(linux_sys_llistxattr) 631 LINUX_NOT_SUPPORTED(linux_sys_flistxattr) 632 633 LINUX_NOT_SUPPORTED(linux_sys_removexattr) 634 LINUX_NOT_SUPPORTED(linux_sys_lremovexattr) 635 LINUX_NOT_SUPPORTED(linux_sys_fremovexattr) 636 637