linux/fs/stat.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  linux/fs/stat.c
   4 *
   5 *  Copyright (C) 1991, 1992  Linus Torvalds
   6 */
   7
   8#include <linux/export.h>
   9#include <linux/mm.h>
  10#include <linux/errno.h>
  11#include <linux/file.h>
  12#include <linux/highuid.h>
  13#include <linux/fs.h>
  14#include <linux/namei.h>
  15#include <linux/security.h>
  16#include <linux/cred.h>
  17#include <linux/syscalls.h>
  18#include <linux/pagemap.h>
  19#include <linux/compat.h>
  20
  21#include <linux/uaccess.h>
  22#include <asm/unistd.h>
  23
  24#include "internal.h"
  25#include "mount.h"
  26
  27/**
  28 * generic_fillattr - Fill in the basic attributes from the inode struct
  29 * @inode: Inode to use as the source
  30 * @stat: Where to fill in the attributes
  31 *
  32 * Fill in the basic attributes in the kstat structure from data that's to be
  33 * found on the VFS inode structure.  This is the default if no getattr inode
  34 * operation is supplied.
  35 */
  36void generic_fillattr(struct inode *inode, struct kstat *stat)
  37{
  38        stat->dev = inode->i_sb->s_dev;
  39        stat->ino = inode->i_ino;
  40        stat->mode = inode->i_mode;
  41        stat->nlink = inode->i_nlink;
  42        stat->uid = inode->i_uid;
  43        stat->gid = inode->i_gid;
  44        stat->rdev = inode->i_rdev;
  45        stat->size = i_size_read(inode);
  46        stat->atime = inode->i_atime;
  47        stat->mtime = inode->i_mtime;
  48        stat->ctime = inode->i_ctime;
  49        stat->blksize = i_blocksize(inode);
  50        stat->blocks = inode->i_blocks;
  51}
  52EXPORT_SYMBOL(generic_fillattr);
  53
  54/**
  55 * vfs_getattr_nosec - getattr without security checks
  56 * @path: file to get attributes from
  57 * @stat: structure to return attributes in
  58 * @request_mask: STATX_xxx flags indicating what the caller wants
  59 * @query_flags: Query mode (KSTAT_QUERY_FLAGS)
  60 *
  61 * Get attributes without calling security_inode_getattr.
  62 *
  63 * Currently the only caller other than vfs_getattr is internal to the
  64 * filehandle lookup code, which uses only the inode number and returns no
  65 * attributes to any user.  Any other code probably wants vfs_getattr.
  66 */
  67int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
  68                      u32 request_mask, unsigned int query_flags)
  69{
  70        struct inode *inode = d_backing_inode(path->dentry);
  71
  72        memset(stat, 0, sizeof(*stat));
  73        stat->result_mask |= STATX_BASIC_STATS;
  74        query_flags &= KSTAT_QUERY_FLAGS;
  75
  76        /* allow the fs to override these if it really wants to */
  77        /* SB_NOATIME means filesystem supplies dummy atime value */
  78        if (inode->i_sb->s_flags & SB_NOATIME)
  79                stat->result_mask &= ~STATX_ATIME;
  80        if (IS_AUTOMOUNT(inode))
  81                stat->attributes |= STATX_ATTR_AUTOMOUNT;
  82
  83        if (IS_DAX(inode))
  84                stat->attributes |= STATX_ATTR_DAX;
  85
  86        if (inode->i_op->getattr)
  87                return inode->i_op->getattr(path, stat, request_mask,
  88                                            query_flags);
  89
  90        generic_fillattr(inode, stat);
  91        return 0;
  92}
  93EXPORT_SYMBOL(vfs_getattr_nosec);
  94
  95/*
  96 * vfs_getattr - Get the enhanced basic attributes of a file
  97 * @path: The file of interest
  98 * @stat: Where to return the statistics
  99 * @request_mask: STATX_xxx flags indicating what the caller wants
 100 * @query_flags: Query mode (KSTAT_QUERY_FLAGS)
 101 *
 102 * Ask the filesystem for a file's attributes.  The caller must indicate in
 103 * request_mask and query_flags to indicate what they want.
 104 *
 105 * If the file is remote, the filesystem can be forced to update the attributes
 106 * from the backing store by passing AT_STATX_FORCE_SYNC in query_flags or can
 107 * suppress the update by passing AT_STATX_DONT_SYNC.
 108 *
 109 * Bits must have been set in request_mask to indicate which attributes the
 110 * caller wants retrieving.  Any such attribute not requested may be returned
 111 * anyway, but the value may be approximate, and, if remote, may not have been
 112 * synchronised with the server.
 113 *
 114 * 0 will be returned on success, and a -ve error code if unsuccessful.
 115 */
 116int vfs_getattr(const struct path *path, struct kstat *stat,
 117                u32 request_mask, unsigned int query_flags)
 118{
 119        int retval;
 120
 121        retval = security_inode_getattr(path);
 122        if (retval)
 123                return retval;
 124        return vfs_getattr_nosec(path, stat, request_mask, query_flags);
 125}
 126EXPORT_SYMBOL(vfs_getattr);
 127
 128/**
 129 * vfs_statx_fd - Get the enhanced basic attributes by file descriptor
 130 * @fd: The file descriptor referring to the file of interest
 131 * @stat: The result structure to fill in.
 132 * @request_mask: STATX_xxx flags indicating what the caller wants
 133 * @query_flags: Query mode (KSTAT_QUERY_FLAGS)
 134 *
 135 * This function is a wrapper around vfs_getattr().  The main difference is
 136 * that it uses a file descriptor to determine the file location.
 137 *
 138 * 0 will be returned on success, and a -ve error code if unsuccessful.
 139 */
 140int vfs_statx_fd(unsigned int fd, struct kstat *stat,
 141                 u32 request_mask, unsigned int query_flags)
 142{
 143        struct fd f;
 144        int error = -EBADF;
 145
 146        if (query_flags & ~KSTAT_QUERY_FLAGS)
 147                return -EINVAL;
 148
 149        f = fdget_raw(fd);
 150        if (f.file) {
 151                error = vfs_getattr(&f.file->f_path, stat,
 152                                    request_mask, query_flags);
 153                fdput(f);
 154        }
 155        return error;
 156}
 157EXPORT_SYMBOL(vfs_statx_fd);
 158
 159static inline unsigned vfs_stat_set_lookup_flags(unsigned *lookup_flags,
 160                                                 int flags)
 161{
 162        if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
 163                       AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
 164                return -EINVAL;
 165
 166        *lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
 167        if (flags & AT_SYMLINK_NOFOLLOW)
 168                *lookup_flags &= ~LOOKUP_FOLLOW;
 169        if (flags & AT_NO_AUTOMOUNT)
 170                *lookup_flags &= ~LOOKUP_AUTOMOUNT;
 171        if (flags & AT_EMPTY_PATH)
 172                *lookup_flags |= LOOKUP_EMPTY;
 173
 174        return 0;
 175}
 176
 177/**
 178 * vfs_statx - Get basic and extra attributes by filename
 179 * @dfd: A file descriptor representing the base dir for a relative filename
 180 * @filename: The name of the file of interest
 181 * @flags: Flags to control the query
 182 * @stat: The result structure to fill in.
 183 * @request_mask: STATX_xxx flags indicating what the caller wants
 184 *
 185 * This function is a wrapper around vfs_getattr().  The main difference is
 186 * that it uses a filename and base directory to determine the file location.
 187 * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink
 188 * at the given name from being referenced.
 189 *
 190 * 0 will be returned on success, and a -ve error code if unsuccessful.
 191 */
 192int vfs_statx(int dfd, const char __user *filename, int flags,
 193              struct kstat *stat, u32 request_mask)
 194{
 195        struct path path;
 196        int error = -EINVAL;
 197        unsigned lookup_flags;
 198
 199        if (vfs_stat_set_lookup_flags(&lookup_flags, flags))
 200                return -EINVAL;
 201retry:
 202        error = user_path_at(dfd, filename, lookup_flags, &path);
 203        if (error)
 204                goto out;
 205
 206        error = vfs_getattr(&path, stat, request_mask, flags);
 207        stat->mnt_id = real_mount(path.mnt)->mnt_id;
 208        stat->result_mask |= STATX_MNT_ID;
 209        if (path.mnt->mnt_root == path.dentry)
 210                stat->attributes |= STATX_ATTR_MOUNT_ROOT;
 211        stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT;
 212        path_put(&path);
 213        if (retry_estale(error, lookup_flags)) {
 214                lookup_flags |= LOOKUP_REVAL;
 215                goto retry;
 216        }
 217out:
 218        return error;
 219}
 220EXPORT_SYMBOL(vfs_statx);
 221
 222
 223#ifdef __ARCH_WANT_OLD_STAT
 224
 225/*
 226 * For backward compatibility?  Maybe this should be moved
 227 * into arch/i386 instead?
 228 */
 229static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
 230{
 231        static int warncount = 5;
 232        struct __old_kernel_stat tmp;
 233
 234        if (warncount > 0) {
 235                warncount--;
 236                printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
 237                        current->comm);
 238        } else if (warncount < 0) {
 239                /* it's laughable, but... */
 240                warncount = 0;
 241        }
 242
 243        memset(&tmp, 0, sizeof(struct __old_kernel_stat));
 244        tmp.st_dev = old_encode_dev(stat->dev);
 245        tmp.st_ino = stat->ino;
 246        if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
 247                return -EOVERFLOW;
 248        tmp.st_mode = stat->mode;
 249        tmp.st_nlink = stat->nlink;
 250        if (tmp.st_nlink != stat->nlink)
 251                return -EOVERFLOW;
 252        SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
 253        SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
 254        tmp.st_rdev = old_encode_dev(stat->rdev);
 255#if BITS_PER_LONG == 32
 256        if (stat->size > MAX_NON_LFS)
 257                return -EOVERFLOW;
 258#endif
 259        tmp.st_size = stat->size;
 260        tmp.st_atime = stat->atime.tv_sec;
 261        tmp.st_mtime = stat->mtime.tv_sec;
 262        tmp.st_ctime = stat->ctime.tv_sec;
 263        return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
 264}
 265
 266SYSCALL_DEFINE2(stat, const char __user *, filename,
 267                struct __old_kernel_stat __user *, statbuf)
 268{
 269        struct kstat stat;
 270        int error;
 271
 272        error = vfs_stat(filename, &stat);
 273        if (error)
 274                return error;
 275
 276        return cp_old_stat(&stat, statbuf);
 277}
 278
 279SYSCALL_DEFINE2(lstat, const char __user *, filename,
 280                struct __old_kernel_stat __user *, statbuf)
 281{
 282        struct kstat stat;
 283        int error;
 284
 285        error = vfs_lstat(filename, &stat);
 286        if (error)
 287                return error;
 288
 289        return cp_old_stat(&stat, statbuf);
 290}
 291
 292SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
 293{
 294        struct kstat stat;
 295        int error = vfs_fstat(fd, &stat);
 296
 297        if (!error)
 298                error = cp_old_stat(&stat, statbuf);
 299
 300        return error;
 301}
 302
 303#endif /* __ARCH_WANT_OLD_STAT */
 304
 305#ifdef __ARCH_WANT_NEW_STAT
 306
 307#if BITS_PER_LONG == 32
 308#  define choose_32_64(a,b) a
 309#else
 310#  define choose_32_64(a,b) b
 311#endif
 312
 313#define valid_dev(x)  choose_32_64(old_valid_dev(x),true)
 314#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
 315
 316#ifndef INIT_STRUCT_STAT_PADDING
 317#  define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
 318#endif
 319
 320static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
 321{
 322        struct stat tmp;
 323
 324        if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
 325                return -EOVERFLOW;
 326#if BITS_PER_LONG == 32
 327        if (stat->size > MAX_NON_LFS)
 328                return -EOVERFLOW;
 329#endif
 330
 331        INIT_STRUCT_STAT_PADDING(tmp);
 332        tmp.st_dev = encode_dev(stat->dev);
 333        tmp.st_ino = stat->ino;
 334        if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
 335                return -EOVERFLOW;
 336        tmp.st_mode = stat->mode;
 337        tmp.st_nlink = stat->nlink;
 338        if (tmp.st_nlink != stat->nlink)
 339                return -EOVERFLOW;
 340        SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
 341        SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
 342        tmp.st_rdev = encode_dev(stat->rdev);
 343        tmp.st_size = stat->size;
 344        tmp.st_atime = stat->atime.tv_sec;
 345        tmp.st_mtime = stat->mtime.tv_sec;
 346        tmp.st_ctime = stat->ctime.tv_sec;
 347#ifdef STAT_HAVE_NSEC
 348        tmp.st_atime_nsec = stat->atime.tv_nsec;
 349        tmp.st_mtime_nsec = stat->mtime.tv_nsec;
 350        tmp.st_ctime_nsec = stat->ctime.tv_nsec;
 351#endif
 352        tmp.st_blocks = stat->blocks;
 353        tmp.st_blksize = stat->blksize;
 354        return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
 355}
 356
 357SYSCALL_DEFINE2(newstat, const char __user *, filename,
 358                struct stat __user *, statbuf)
 359{
 360        struct kstat stat;
 361        int error = vfs_stat(filename, &stat);
 362
 363        if (error)
 364                return error;
 365        return cp_new_stat(&stat, statbuf);
 366}
 367
 368SYSCALL_DEFINE2(newlstat, const char __user *, filename,
 369                struct stat __user *, statbuf)
 370{
 371        struct kstat stat;
 372        int error;
 373
 374        error = vfs_lstat(filename, &stat);
 375        if (error)
 376                return error;
 377
 378        return cp_new_stat(&stat, statbuf);
 379}
 380
 381#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
 382SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
 383                struct stat __user *, statbuf, int, flag)
 384{
 385        struct kstat stat;
 386        int error;
 387
 388        error = vfs_fstatat(dfd, filename, &stat, flag);
 389        if (error)
 390                return error;
 391        return cp_new_stat(&stat, statbuf);
 392}
 393#endif
 394
 395SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
 396{
 397        struct kstat stat;
 398        int error = vfs_fstat(fd, &stat);
 399
 400        if (!error)
 401                error = cp_new_stat(&stat, statbuf);
 402
 403        return error;
 404}
 405#endif
 406
 407static int do_readlinkat(int dfd, const char __user *pathname,
 408                         char __user *buf, int bufsiz)
 409{
 410        struct path path;
 411        int error;
 412        int empty = 0;
 413        unsigned int lookup_flags = LOOKUP_EMPTY;
 414
 415        if (bufsiz <= 0)
 416                return -EINVAL;
 417
 418retry:
 419        error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
 420        if (!error) {
 421                struct inode *inode = d_backing_inode(path.dentry);
 422
 423                error = empty ? -ENOENT : -EINVAL;
 424                /*
 425                 * AFS mountpoints allow readlink(2) but are not symlinks
 426                 */
 427                if (d_is_symlink(path.dentry) || inode->i_op->readlink) {
 428                        error = security_inode_readlink(path.dentry);
 429                        if (!error) {
 430                                touch_atime(&path);
 431                                error = vfs_readlink(path.dentry, buf, bufsiz);
 432                        }
 433                }
 434                path_put(&path);
 435                if (retry_estale(error, lookup_flags)) {
 436                        lookup_flags |= LOOKUP_REVAL;
 437                        goto retry;
 438                }
 439        }
 440        return error;
 441}
 442
 443SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
 444                char __user *, buf, int, bufsiz)
 445{
 446        return do_readlinkat(dfd, pathname, buf, bufsiz);
 447}
 448
 449SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
 450                int, bufsiz)
 451{
 452        return do_readlinkat(AT_FDCWD, path, buf, bufsiz);
 453}
 454
 455
 456/* ---------- LFS-64 ----------- */
 457#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
 458
 459#ifndef INIT_STRUCT_STAT64_PADDING
 460#  define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
 461#endif
 462
 463static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
 464{
 465        struct stat64 tmp;
 466
 467        INIT_STRUCT_STAT64_PADDING(tmp);
 468#ifdef CONFIG_MIPS
 469        /* mips has weird padding, so we don't get 64 bits there */
 470        tmp.st_dev = new_encode_dev(stat->dev);
 471        tmp.st_rdev = new_encode_dev(stat->rdev);
 472#else
 473        tmp.st_dev = huge_encode_dev(stat->dev);
 474        tmp.st_rdev = huge_encode_dev(stat->rdev);
 475#endif
 476        tmp.st_ino = stat->ino;
 477        if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
 478                return -EOVERFLOW;
 479#ifdef STAT64_HAS_BROKEN_ST_INO
 480        tmp.__st_ino = stat->ino;
 481#endif
 482        tmp.st_mode = stat->mode;
 483        tmp.st_nlink = stat->nlink;
 484        tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
 485        tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
 486        tmp.st_atime = stat->atime.tv_sec;
 487        tmp.st_atime_nsec = stat->atime.tv_nsec;
 488        tmp.st_mtime = stat->mtime.tv_sec;
 489        tmp.st_mtime_nsec = stat->mtime.tv_nsec;
 490        tmp.st_ctime = stat->ctime.tv_sec;
 491        tmp.st_ctime_nsec = stat->ctime.tv_nsec;
 492        tmp.st_size = stat->size;
 493        tmp.st_blocks = stat->blocks;
 494        tmp.st_blksize = stat->blksize;
 495        return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
 496}
 497
 498SYSCALL_DEFINE2(stat64, const char __user *, filename,
 499                struct stat64 __user *, statbuf)
 500{
 501        struct kstat stat;
 502        int error = vfs_stat(filename, &stat);
 503
 504        if (!error)
 505                error = cp_new_stat64(&stat, statbuf);
 506
 507        return error;
 508}
 509
 510SYSCALL_DEFINE2(lstat64, const char __user *, filename,
 511                struct stat64 __user *, statbuf)
 512{
 513        struct kstat stat;
 514        int error = vfs_lstat(filename, &stat);
 515
 516        if (!error)
 517                error = cp_new_stat64(&stat, statbuf);
 518
 519        return error;
 520}
 521
 522SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
 523{
 524        struct kstat stat;
 525        int error = vfs_fstat(fd, &stat);
 526
 527        if (!error)
 528                error = cp_new_stat64(&stat, statbuf);
 529
 530        return error;
 531}
 532
 533SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
 534                struct stat64 __user *, statbuf, int, flag)
 535{
 536        struct kstat stat;
 537        int error;
 538
 539        error = vfs_fstatat(dfd, filename, &stat, flag);
 540        if (error)
 541                return error;
 542        return cp_new_stat64(&stat, statbuf);
 543}
 544#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
 545
 546static noinline_for_stack int
 547cp_statx(const struct kstat *stat, struct statx __user *buffer)
 548{
 549        struct statx tmp;
 550
 551        memset(&tmp, 0, sizeof(tmp));
 552
 553        tmp.stx_mask = stat->result_mask;
 554        tmp.stx_blksize = stat->blksize;
 555        tmp.stx_attributes = stat->attributes;
 556        tmp.stx_nlink = stat->nlink;
 557        tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid);
 558        tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid);
 559        tmp.stx_mode = stat->mode;
 560        tmp.stx_ino = stat->ino;
 561        tmp.stx_size = stat->size;
 562        tmp.stx_blocks = stat->blocks;
 563        tmp.stx_attributes_mask = stat->attributes_mask;
 564        tmp.stx_atime.tv_sec = stat->atime.tv_sec;
 565        tmp.stx_atime.tv_nsec = stat->atime.tv_nsec;
 566        tmp.stx_btime.tv_sec = stat->btime.tv_sec;
 567        tmp.stx_btime.tv_nsec = stat->btime.tv_nsec;
 568        tmp.stx_ctime.tv_sec = stat->ctime.tv_sec;
 569        tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec;
 570        tmp.stx_mtime.tv_sec = stat->mtime.tv_sec;
 571        tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec;
 572        tmp.stx_rdev_major = MAJOR(stat->rdev);
 573        tmp.stx_rdev_minor = MINOR(stat->rdev);
 574        tmp.stx_dev_major = MAJOR(stat->dev);
 575        tmp.stx_dev_minor = MINOR(stat->dev);
 576        tmp.stx_mnt_id = stat->mnt_id;
 577
 578        return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 579}
 580
 581int do_statx(int dfd, const char __user *filename, unsigned flags,
 582             unsigned int mask, struct statx __user *buffer)
 583{
 584        struct kstat stat;
 585        int error;
 586
 587        if (mask & STATX__RESERVED)
 588                return -EINVAL;
 589        if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
 590                return -EINVAL;
 591
 592        error = vfs_statx(dfd, filename, flags, &stat, mask);
 593        if (error)
 594                return error;
 595
 596        return cp_statx(&stat, buffer);
 597}
 598
 599/**
 600 * sys_statx - System call to get enhanced stats
 601 * @dfd: Base directory to pathwalk from *or* fd to stat.
 602 * @filename: File to stat or "" with AT_EMPTY_PATH
 603 * @flags: AT_* flags to control pathwalk.
 604 * @mask: Parts of statx struct actually required.
 605 * @buffer: Result buffer.
 606 *
 607 * Note that fstat() can be emulated by setting dfd to the fd of interest,
 608 * supplying "" as the filename and setting AT_EMPTY_PATH in the flags.
 609 */
 610SYSCALL_DEFINE5(statx,
 611                int, dfd, const char __user *, filename, unsigned, flags,
 612                unsigned int, mask,
 613                struct statx __user *, buffer)
 614{
 615        return do_statx(dfd, filename, flags, mask, buffer);
 616}
 617
 618#ifdef CONFIG_COMPAT
 619static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
 620{
 621        struct compat_stat tmp;
 622
 623        if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
 624                return -EOVERFLOW;
 625
 626        memset(&tmp, 0, sizeof(tmp));
 627        tmp.st_dev = old_encode_dev(stat->dev);
 628        tmp.st_ino = stat->ino;
 629        if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
 630                return -EOVERFLOW;
 631        tmp.st_mode = stat->mode;
 632        tmp.st_nlink = stat->nlink;
 633        if (tmp.st_nlink != stat->nlink)
 634                return -EOVERFLOW;
 635        SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
 636        SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
 637        tmp.st_rdev = old_encode_dev(stat->rdev);
 638        if ((u64) stat->size > MAX_NON_LFS)
 639                return -EOVERFLOW;
 640        tmp.st_size = stat->size;
 641        tmp.st_atime = stat->atime.tv_sec;
 642        tmp.st_atime_nsec = stat->atime.tv_nsec;
 643        tmp.st_mtime = stat->mtime.tv_sec;
 644        tmp.st_mtime_nsec = stat->mtime.tv_nsec;
 645        tmp.st_ctime = stat->ctime.tv_sec;
 646        tmp.st_ctime_nsec = stat->ctime.tv_nsec;
 647        tmp.st_blocks = stat->blocks;
 648        tmp.st_blksize = stat->blksize;
 649        return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 650}
 651
 652COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename,
 653                       struct compat_stat __user *, statbuf)
 654{
 655        struct kstat stat;
 656        int error;
 657
 658        error = vfs_stat(filename, &stat);
 659        if (error)
 660                return error;
 661        return cp_compat_stat(&stat, statbuf);
 662}
 663
 664COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename,
 665                       struct compat_stat __user *, statbuf)
 666{
 667        struct kstat stat;
 668        int error;
 669
 670        error = vfs_lstat(filename, &stat);
 671        if (error)
 672                return error;
 673        return cp_compat_stat(&stat, statbuf);
 674}
 675
 676#ifndef __ARCH_WANT_STAT64
 677COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd,
 678                       const char __user *, filename,
 679                       struct compat_stat __user *, statbuf, int, flag)
 680{
 681        struct kstat stat;
 682        int error;
 683
 684        error = vfs_fstatat(dfd, filename, &stat, flag);
 685        if (error)
 686                return error;
 687        return cp_compat_stat(&stat, statbuf);
 688}
 689#endif
 690
 691COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd,
 692                       struct compat_stat __user *, statbuf)
 693{
 694        struct kstat stat;
 695        int error = vfs_fstat(fd, &stat);
 696
 697        if (!error)
 698                error = cp_compat_stat(&stat, statbuf);
 699        return error;
 700}
 701#endif
 702
 703/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
 704void __inode_add_bytes(struct inode *inode, loff_t bytes)
 705{
 706        inode->i_blocks += bytes >> 9;
 707        bytes &= 511;
 708        inode->i_bytes += bytes;
 709        if (inode->i_bytes >= 512) {
 710                inode->i_blocks++;
 711                inode->i_bytes -= 512;
 712        }
 713}
 714EXPORT_SYMBOL(__inode_add_bytes);
 715
 716void inode_add_bytes(struct inode *inode, loff_t bytes)
 717{
 718        spin_lock(&inode->i_lock);
 719        __inode_add_bytes(inode, bytes);
 720        spin_unlock(&inode->i_lock);
 721}
 722
 723EXPORT_SYMBOL(inode_add_bytes);
 724
 725void __inode_sub_bytes(struct inode *inode, loff_t bytes)
 726{
 727        inode->i_blocks -= bytes >> 9;
 728        bytes &= 511;
 729        if (inode->i_bytes < bytes) {
 730                inode->i_blocks--;
 731                inode->i_bytes += 512;
 732        }
 733        inode->i_bytes -= bytes;
 734}
 735
 736EXPORT_SYMBOL(__inode_sub_bytes);
 737
 738void inode_sub_bytes(struct inode *inode, loff_t bytes)
 739{
 740        spin_lock(&inode->i_lock);
 741        __inode_sub_bytes(inode, bytes);
 742        spin_unlock(&inode->i_lock);
 743}
 744
 745EXPORT_SYMBOL(inode_sub_bytes);
 746
 747loff_t inode_get_bytes(struct inode *inode)
 748{
 749        loff_t ret;
 750
 751        spin_lock(&inode->i_lock);
 752        ret = __inode_get_bytes(inode);
 753        spin_unlock(&inode->i_lock);
 754        return ret;
 755}
 756
 757EXPORT_SYMBOL(inode_get_bytes);
 758
 759void inode_set_bytes(struct inode *inode, loff_t bytes)
 760{
 761        /* Caller is here responsible for sufficient locking
 762         * (ie. inode->i_lock) */
 763        inode->i_blocks = bytes >> 9;
 764        inode->i_bytes = bytes & 511;
 765}
 766
 767EXPORT_SYMBOL(inode_set_bytes);
 768