linux/fs/ioctl.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  linux/fs/ioctl.c
   4 *
   5 *  Copyright (C) 1991, 1992  Linus Torvalds
   6 */
   7
   8#include <linux/syscalls.h>
   9#include <linux/mm.h>
  10#include <linux/capability.h>
  11#include <linux/compat.h>
  12#include <linux/file.h>
  13#include <linux/fs.h>
  14#include <linux/security.h>
  15#include <linux/export.h>
  16#include <linux/uaccess.h>
  17#include <linux/writeback.h>
  18#include <linux/buffer_head.h>
  19#include <linux/falloc.h>
  20#include <linux/sched/signal.h>
  21#include <linux/fiemap.h>
  22#include <linux/mount.h>
  23#include <linux/fscrypt.h>
  24#include <linux/fileattr.h>
  25
  26#include "internal.h"
  27
  28#include <asm/ioctls.h>
  29
  30/* So that the fiemap access checks can't overflow on 32 bit machines. */
  31#define FIEMAP_MAX_EXTENTS      (UINT_MAX / sizeof(struct fiemap_extent))
  32
  33/**
  34 * vfs_ioctl - call filesystem specific ioctl methods
  35 * @filp:       open file to invoke ioctl method on
  36 * @cmd:        ioctl command to execute
  37 * @arg:        command-specific argument for ioctl
  38 *
  39 * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
  40 * returns -ENOTTY.
  41 *
  42 * Returns 0 on success, -errno on error.
  43 */
  44long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  45{
  46        int error = -ENOTTY;
  47
  48        if (!filp->f_op->unlocked_ioctl)
  49                goto out;
  50
  51        error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
  52        if (error == -ENOIOCTLCMD)
  53                error = -ENOTTY;
  54 out:
  55        return error;
  56}
  57EXPORT_SYMBOL(vfs_ioctl);
  58
  59static int ioctl_fibmap(struct file *filp, int __user *p)
  60{
  61        struct inode *inode = file_inode(filp);
  62        struct super_block *sb = inode->i_sb;
  63        int error, ur_block;
  64        sector_t block;
  65
  66        if (!capable(CAP_SYS_RAWIO))
  67                return -EPERM;
  68
  69        error = get_user(ur_block, p);
  70        if (error)
  71                return error;
  72
  73        if (ur_block < 0)
  74                return -EINVAL;
  75
  76        block = ur_block;
  77        error = bmap(inode, &block);
  78
  79        if (block > INT_MAX) {
  80                error = -ERANGE;
  81                pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n",
  82                                    current->comm, task_pid_nr(current),
  83                                    sb->s_id, filp);
  84        }
  85
  86        if (error)
  87                ur_block = 0;
  88        else
  89                ur_block = block;
  90
  91        if (put_user(ur_block, p))
  92                error = -EFAULT;
  93
  94        return error;
  95}
  96
  97/**
  98 * fiemap_fill_next_extent - Fiemap helper function
  99 * @fieinfo:    Fiemap context passed into ->fiemap
 100 * @logical:    Extent logical start offset, in bytes
 101 * @phys:       Extent physical start offset, in bytes
 102 * @len:        Extent length, in bytes
 103 * @flags:      FIEMAP_EXTENT flags that describe this extent
 104 *
 105 * Called from file system ->fiemap callback. Will populate extent
 106 * info as passed in via arguments and copy to user memory. On
 107 * success, extent count on fieinfo is incremented.
 108 *
 109 * Returns 0 on success, -errno on error, 1 if this was the last
 110 * extent that will fit in user array.
 111 */
 112#define SET_UNKNOWN_FLAGS       (FIEMAP_EXTENT_DELALLOC)
 113#define SET_NO_UNMOUNTED_IO_FLAGS       (FIEMAP_EXTENT_DATA_ENCRYPTED)
 114#define SET_NOT_ALIGNED_FLAGS   (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
 115int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
 116                            u64 phys, u64 len, u32 flags)
 117{
 118        struct fiemap_extent extent;
 119        struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
 120
 121        /* only count the extents */
 122        if (fieinfo->fi_extents_max == 0) {
 123                fieinfo->fi_extents_mapped++;
 124                return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
 125        }
 126
 127        if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
 128                return 1;
 129
 130        if (flags & SET_UNKNOWN_FLAGS)
 131                flags |= FIEMAP_EXTENT_UNKNOWN;
 132        if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
 133                flags |= FIEMAP_EXTENT_ENCODED;
 134        if (flags & SET_NOT_ALIGNED_FLAGS)
 135                flags |= FIEMAP_EXTENT_NOT_ALIGNED;
 136
 137        memset(&extent, 0, sizeof(extent));
 138        extent.fe_logical = logical;
 139        extent.fe_physical = phys;
 140        extent.fe_length = len;
 141        extent.fe_flags = flags;
 142
 143        dest += fieinfo->fi_extents_mapped;
 144        if (copy_to_user(dest, &extent, sizeof(extent)))
 145                return -EFAULT;
 146
 147        fieinfo->fi_extents_mapped++;
 148        if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
 149                return 1;
 150        return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
 151}
 152EXPORT_SYMBOL(fiemap_fill_next_extent);
 153
 154/**
 155 * fiemap_prep - check validity of requested flags for fiemap
 156 * @inode:      Inode to operate on
 157 * @fieinfo:    Fiemap context passed into ->fiemap
 158 * @start:      Start of the mapped range
 159 * @len:        Length of the mapped range, can be truncated by this function.
 160 * @supported_flags:    Set of fiemap flags that the file system understands
 161 *
 162 * This function must be called from each ->fiemap instance to validate the
 163 * fiemap request against the file system parameters.
 164 *
 165 * Returns 0 on success, or a negative error on failure.
 166 */
 167int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
 168                u64 start, u64 *len, u32 supported_flags)
 169{
 170        u64 maxbytes = inode->i_sb->s_maxbytes;
 171        u32 incompat_flags;
 172        int ret = 0;
 173
 174        if (*len == 0)
 175                return -EINVAL;
 176        if (start > maxbytes)
 177                return -EFBIG;
 178
 179        /*
 180         * Shrink request scope to what the fs can actually handle.
 181         */
 182        if (*len > maxbytes || (maxbytes - *len) < start)
 183                *len = maxbytes - start;
 184
 185        supported_flags |= FIEMAP_FLAG_SYNC;
 186        supported_flags &= FIEMAP_FLAGS_COMPAT;
 187        incompat_flags = fieinfo->fi_flags & ~supported_flags;
 188        if (incompat_flags) {
 189                fieinfo->fi_flags = incompat_flags;
 190                return -EBADR;
 191        }
 192
 193        if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
 194                ret = filemap_write_and_wait(inode->i_mapping);
 195        return ret;
 196}
 197EXPORT_SYMBOL(fiemap_prep);
 198
 199static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap)
 200{
 201        struct fiemap fiemap;
 202        struct fiemap_extent_info fieinfo = { 0, };
 203        struct inode *inode = file_inode(filp);
 204        int error;
 205
 206        if (!inode->i_op->fiemap)
 207                return -EOPNOTSUPP;
 208
 209        if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
 210                return -EFAULT;
 211
 212        if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
 213                return -EINVAL;
 214
 215        fieinfo.fi_flags = fiemap.fm_flags;
 216        fieinfo.fi_extents_max = fiemap.fm_extent_count;
 217        fieinfo.fi_extents_start = ufiemap->fm_extents;
 218
 219        error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start,
 220                        fiemap.fm_length);
 221
 222        fiemap.fm_flags = fieinfo.fi_flags;
 223        fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
 224        if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
 225                error = -EFAULT;
 226
 227        return error;
 228}
 229
 230static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
 231                             u64 off, u64 olen, u64 destoff)
 232{
 233        struct fd src_file = fdget(srcfd);
 234        loff_t cloned;
 235        int ret;
 236
 237        if (!src_file.file)
 238                return -EBADF;
 239        ret = -EXDEV;
 240        if (src_file.file->f_path.mnt != dst_file->f_path.mnt)
 241                goto fdput;
 242        cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff,
 243                                      olen, 0);
 244        if (cloned < 0)
 245                ret = cloned;
 246        else if (olen && cloned != olen)
 247                ret = -EINVAL;
 248        else
 249                ret = 0;
 250fdput:
 251        fdput(src_file);
 252        return ret;
 253}
 254
 255static long ioctl_file_clone_range(struct file *file,
 256                                   struct file_clone_range __user *argp)
 257{
 258        struct file_clone_range args;
 259
 260        if (copy_from_user(&args, argp, sizeof(args)))
 261                return -EFAULT;
 262        return ioctl_file_clone(file, args.src_fd, args.src_offset,
 263                                args.src_length, args.dest_offset);
 264}
 265
 266#ifdef CONFIG_BLOCK
 267
 268static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
 269{
 270        return (offset >> inode->i_blkbits);
 271}
 272
 273static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
 274{
 275        return (blk << inode->i_blkbits);
 276}
 277
 278/**
 279 * __generic_block_fiemap - FIEMAP for block based inodes (no locking)
 280 * @inode: the inode to map
 281 * @fieinfo: the fiemap info struct that will be passed back to userspace
 282 * @start: where to start mapping in the inode
 283 * @len: how much space to map
 284 * @get_block: the fs's get_block function
 285 *
 286 * This does FIEMAP for block based inodes.  Basically it will just loop
 287 * through get_block until we hit the number of extents we want to map, or we
 288 * go past the end of the file and hit a hole.
 289 *
 290 * If it is possible to have data blocks beyond a hole past @inode->i_size, then
 291 * please do not use this function, it will stop at the first unmapped block
 292 * beyond i_size.
 293 *
 294 * If you use this function directly, you need to do your own locking. Use
 295 * generic_block_fiemap if you want the locking done for you.
 296 */
 297static int __generic_block_fiemap(struct inode *inode,
 298                           struct fiemap_extent_info *fieinfo, loff_t start,
 299                           loff_t len, get_block_t *get_block)
 300{
 301        struct buffer_head map_bh;
 302        sector_t start_blk, last_blk;
 303        loff_t isize = i_size_read(inode);
 304        u64 logical = 0, phys = 0, size = 0;
 305        u32 flags = FIEMAP_EXTENT_MERGED;
 306        bool past_eof = false, whole_file = false;
 307        int ret = 0;
 308
 309        ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC);
 310        if (ret)
 311                return ret;
 312
 313        /*
 314         * Either the i_mutex or other appropriate locking needs to be held
 315         * since we expect isize to not change at all through the duration of
 316         * this call.
 317         */
 318        if (len >= isize) {
 319                whole_file = true;
 320                len = isize;
 321        }
 322
 323        /*
 324         * Some filesystems can't deal with being asked to map less than
 325         * blocksize, so make sure our len is at least block length.
 326         */
 327        if (logical_to_blk(inode, len) == 0)
 328                len = blk_to_logical(inode, 1);
 329
 330        start_blk = logical_to_blk(inode, start);
 331        last_blk = logical_to_blk(inode, start + len - 1);
 332
 333        do {
 334                /*
 335                 * we set b_size to the total size we want so it will map as
 336                 * many contiguous blocks as possible at once
 337                 */
 338                memset(&map_bh, 0, sizeof(struct buffer_head));
 339                map_bh.b_size = len;
 340
 341                ret = get_block(inode, start_blk, &map_bh, 0);
 342                if (ret)
 343                        break;
 344
 345                /* HOLE */
 346                if (!buffer_mapped(&map_bh)) {
 347                        start_blk++;
 348
 349                        /*
 350                         * We want to handle the case where there is an
 351                         * allocated block at the front of the file, and then
 352                         * nothing but holes up to the end of the file properly,
 353                         * to make sure that extent at the front gets properly
 354                         * marked with FIEMAP_EXTENT_LAST
 355                         */
 356                        if (!past_eof &&
 357                            blk_to_logical(inode, start_blk) >= isize)
 358                                past_eof = 1;
 359
 360                        /*
 361                         * First hole after going past the EOF, this is our
 362                         * last extent
 363                         */
 364                        if (past_eof && size) {
 365                                flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
 366                                ret = fiemap_fill_next_extent(fieinfo, logical,
 367                                                              phys, size,
 368                                                              flags);
 369                        } else if (size) {
 370                                ret = fiemap_fill_next_extent(fieinfo, logical,
 371                                                              phys, size, flags);
 372                                size = 0;
 373                        }
 374
 375                        /* if we have holes up to/past EOF then we're done */
 376                        if (start_blk > last_blk || past_eof || ret)
 377                                break;
 378                } else {
 379                        /*
 380                         * We have gone over the length of what we wanted to
 381                         * map, and it wasn't the entire file, so add the extent
 382                         * we got last time and exit.
 383                         *
 384                         * This is for the case where say we want to map all the
 385                         * way up to the second to the last block in a file, but
 386                         * the last block is a hole, making the second to last
 387                         * block FIEMAP_EXTENT_LAST.  In this case we want to
 388                         * see if there is a hole after the second to last block
 389                         * so we can mark it properly.  If we found data after
 390                         * we exceeded the length we were requesting, then we
 391                         * are good to go, just add the extent to the fieinfo
 392                         * and break
 393                         */
 394                        if (start_blk > last_blk && !whole_file) {
 395                                ret = fiemap_fill_next_extent(fieinfo, logical,
 396                                                              phys, size,
 397                                                              flags);
 398                                break;
 399                        }
 400
 401                        /*
 402                         * if size != 0 then we know we already have an extent
 403                         * to add, so add it.
 404                         */
 405                        if (size) {
 406                                ret = fiemap_fill_next_extent(fieinfo, logical,
 407                                                              phys, size,
 408                                                              flags);
 409                                if (ret)
 410                                        break;
 411                        }
 412
 413                        logical = blk_to_logical(inode, start_blk);
 414                        phys = blk_to_logical(inode, map_bh.b_blocknr);
 415                        size = map_bh.b_size;
 416                        flags = FIEMAP_EXTENT_MERGED;
 417
 418                        start_blk += logical_to_blk(inode, size);
 419
 420                        /*
 421                         * If we are past the EOF, then we need to make sure as
 422                         * soon as we find a hole that the last extent we found
 423                         * is marked with FIEMAP_EXTENT_LAST
 424                         */
 425                        if (!past_eof && logical + size >= isize)
 426                                past_eof = true;
 427                }
 428                cond_resched();
 429                if (fatal_signal_pending(current)) {
 430                        ret = -EINTR;
 431                        break;
 432                }
 433
 434        } while (1);
 435
 436        /* If ret is 1 then we just hit the end of the extent array */
 437        if (ret == 1)
 438                ret = 0;
 439
 440        return ret;
 441}
 442
 443/**
 444 * generic_block_fiemap - FIEMAP for block based inodes
 445 * @inode: The inode to map
 446 * @fieinfo: The mapping information
 447 * @start: The initial block to map
 448 * @len: The length of the extect to attempt to map
 449 * @get_block: The block mapping function for the fs
 450 *
 451 * Calls __generic_block_fiemap to map the inode, after taking
 452 * the inode's mutex lock.
 453 */
 454
 455int generic_block_fiemap(struct inode *inode,
 456                         struct fiemap_extent_info *fieinfo, u64 start,
 457                         u64 len, get_block_t *get_block)
 458{
 459        int ret;
 460        inode_lock(inode);
 461        ret = __generic_block_fiemap(inode, fieinfo, start, len, get_block);
 462        inode_unlock(inode);
 463        return ret;
 464}
 465EXPORT_SYMBOL(generic_block_fiemap);
 466
 467#endif  /*  CONFIG_BLOCK  */
 468
 469/*
 470 * This provides compatibility with legacy XFS pre-allocation ioctls
 471 * which predate the fallocate syscall.
 472 *
 473 * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
 474 * are used here, rest are ignored.
 475 */
 476static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
 477{
 478        struct inode *inode = file_inode(filp);
 479        struct space_resv sr;
 480
 481        if (copy_from_user(&sr, argp, sizeof(sr)))
 482                return -EFAULT;
 483
 484        switch (sr.l_whence) {
 485        case SEEK_SET:
 486                break;
 487        case SEEK_CUR:
 488                sr.l_start += filp->f_pos;
 489                break;
 490        case SEEK_END:
 491                sr.l_start += i_size_read(inode);
 492                break;
 493        default:
 494                return -EINVAL;
 495        }
 496
 497        return vfs_fallocate(filp, mode | FALLOC_FL_KEEP_SIZE, sr.l_start,
 498                        sr.l_len);
 499}
 500
 501/* on ia32 l_start is on a 32-bit boundary */
 502#if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
 503/* just account for different alignment */
 504static int compat_ioctl_preallocate(struct file *file, int mode,
 505                                    struct space_resv_32 __user *argp)
 506{
 507        struct inode *inode = file_inode(file);
 508        struct space_resv_32 sr;
 509
 510        if (copy_from_user(&sr, argp, sizeof(sr)))
 511                return -EFAULT;
 512
 513        switch (sr.l_whence) {
 514        case SEEK_SET:
 515                break;
 516        case SEEK_CUR:
 517                sr.l_start += file->f_pos;
 518                break;
 519        case SEEK_END:
 520                sr.l_start += i_size_read(inode);
 521                break;
 522        default:
 523                return -EINVAL;
 524        }
 525
 526        return vfs_fallocate(file, mode | FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
 527}
 528#endif
 529
 530static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
 531{
 532        switch (cmd) {
 533        case FIBMAP:
 534                return ioctl_fibmap(filp, p);
 535        case FS_IOC_RESVSP:
 536        case FS_IOC_RESVSP64:
 537                return ioctl_preallocate(filp, 0, p);
 538        case FS_IOC_UNRESVSP:
 539        case FS_IOC_UNRESVSP64:
 540                return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, p);
 541        case FS_IOC_ZERO_RANGE:
 542                return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, p);
 543        }
 544
 545        return -ENOIOCTLCMD;
 546}
 547
 548static int ioctl_fionbio(struct file *filp, int __user *argp)
 549{
 550        unsigned int flag;
 551        int on, error;
 552
 553        error = get_user(on, argp);
 554        if (error)
 555                return error;
 556        flag = O_NONBLOCK;
 557#ifdef __sparc__
 558        /* SunOS compatibility item. */
 559        if (O_NONBLOCK != O_NDELAY)
 560                flag |= O_NDELAY;
 561#endif
 562        spin_lock(&filp->f_lock);
 563        if (on)
 564                filp->f_flags |= flag;
 565        else
 566                filp->f_flags &= ~flag;
 567        spin_unlock(&filp->f_lock);
 568        return error;
 569}
 570
 571static int ioctl_fioasync(unsigned int fd, struct file *filp,
 572                          int __user *argp)
 573{
 574        unsigned int flag;
 575        int on, error;
 576
 577        error = get_user(on, argp);
 578        if (error)
 579                return error;
 580        flag = on ? FASYNC : 0;
 581
 582        /* Did FASYNC state change ? */
 583        if ((flag ^ filp->f_flags) & FASYNC) {
 584                if (filp->f_op->fasync)
 585                        /* fasync() adjusts filp->f_flags */
 586                        error = filp->f_op->fasync(fd, filp, on);
 587                else
 588                        error = -ENOTTY;
 589        }
 590        return error < 0 ? error : 0;
 591}
 592
 593static int ioctl_fsfreeze(struct file *filp)
 594{
 595        struct super_block *sb = file_inode(filp)->i_sb;
 596
 597        if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
 598                return -EPERM;
 599
 600        /* If filesystem doesn't support freeze feature, return. */
 601        if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
 602                return -EOPNOTSUPP;
 603
 604        /* Freeze */
 605        if (sb->s_op->freeze_super)
 606                return sb->s_op->freeze_super(sb);
 607        return freeze_super(sb);
 608}
 609
 610static int ioctl_fsthaw(struct file *filp)
 611{
 612        struct super_block *sb = file_inode(filp)->i_sb;
 613
 614        if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
 615                return -EPERM;
 616
 617        /* Thaw */
 618        if (sb->s_op->thaw_super)
 619                return sb->s_op->thaw_super(sb);
 620        return thaw_super(sb);
 621}
 622
 623static int ioctl_file_dedupe_range(struct file *file,
 624                                   struct file_dedupe_range __user *argp)
 625{
 626        struct file_dedupe_range *same = NULL;
 627        int ret;
 628        unsigned long size;
 629        u16 count;
 630
 631        if (get_user(count, &argp->dest_count)) {
 632                ret = -EFAULT;
 633                goto out;
 634        }
 635
 636        size = offsetof(struct file_dedupe_range __user, info[count]);
 637        if (size > PAGE_SIZE) {
 638                ret = -ENOMEM;
 639                goto out;
 640        }
 641
 642        same = memdup_user(argp, size);
 643        if (IS_ERR(same)) {
 644                ret = PTR_ERR(same);
 645                same = NULL;
 646                goto out;
 647        }
 648
 649        same->dest_count = count;
 650        ret = vfs_dedupe_file_range(file, same);
 651        if (ret)
 652                goto out;
 653
 654        ret = copy_to_user(argp, same, size);
 655        if (ret)
 656                ret = -EFAULT;
 657
 658out:
 659        kfree(same);
 660        return ret;
 661}
 662
 663/**
 664 * fileattr_fill_xflags - initialize fileattr with xflags
 665 * @fa:         fileattr pointer
 666 * @xflags:     FS_XFLAG_* flags
 667 *
 668 * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags).  All
 669 * other fields are zeroed.
 670 */
 671void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
 672{
 673        memset(fa, 0, sizeof(*fa));
 674        fa->fsx_valid = true;
 675        fa->fsx_xflags = xflags;
 676        if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)
 677                fa->flags |= FS_IMMUTABLE_FL;
 678        if (fa->fsx_xflags & FS_XFLAG_APPEND)
 679                fa->flags |= FS_APPEND_FL;
 680        if (fa->fsx_xflags & FS_XFLAG_SYNC)
 681                fa->flags |= FS_SYNC_FL;
 682        if (fa->fsx_xflags & FS_XFLAG_NOATIME)
 683                fa->flags |= FS_NOATIME_FL;
 684        if (fa->fsx_xflags & FS_XFLAG_NODUMP)
 685                fa->flags |= FS_NODUMP_FL;
 686        if (fa->fsx_xflags & FS_XFLAG_DAX)
 687                fa->flags |= FS_DAX_FL;
 688        if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
 689                fa->flags |= FS_PROJINHERIT_FL;
 690}
 691EXPORT_SYMBOL(fileattr_fill_xflags);
 692
 693/**
 694 * fileattr_fill_flags - initialize fileattr with flags
 695 * @fa:         fileattr pointer
 696 * @flags:      FS_*_FL flags
 697 *
 698 * Set ->flags, ->flags_valid and ->fsx_xflags (translated flags).
 699 * All other fields are zeroed.
 700 */
 701void fileattr_fill_flags(struct fileattr *fa, u32 flags)
 702{
 703        memset(fa, 0, sizeof(*fa));
 704        fa->flags_valid = true;
 705        fa->flags = flags;
 706        if (fa->flags & FS_SYNC_FL)
 707                fa->fsx_xflags |= FS_XFLAG_SYNC;
 708        if (fa->flags & FS_IMMUTABLE_FL)
 709                fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
 710        if (fa->flags & FS_APPEND_FL)
 711                fa->fsx_xflags |= FS_XFLAG_APPEND;
 712        if (fa->flags & FS_NODUMP_FL)
 713                fa->fsx_xflags |= FS_XFLAG_NODUMP;
 714        if (fa->flags & FS_NOATIME_FL)
 715                fa->fsx_xflags |= FS_XFLAG_NOATIME;
 716        if (fa->flags & FS_DAX_FL)
 717                fa->fsx_xflags |= FS_XFLAG_DAX;
 718        if (fa->flags & FS_PROJINHERIT_FL)
 719                fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
 720}
 721EXPORT_SYMBOL(fileattr_fill_flags);
 722
 723/**
 724 * vfs_fileattr_get - retrieve miscellaneous file attributes
 725 * @dentry:     the object to retrieve from
 726 * @fa:         fileattr pointer
 727 *
 728 * Call i_op->fileattr_get() callback, if exists.
 729 *
 730 * Return: 0 on success, or a negative error on failure.
 731 */
 732int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 733{
 734        struct inode *inode = d_inode(dentry);
 735
 736        if (!inode->i_op->fileattr_get)
 737                return -ENOIOCTLCMD;
 738
 739        return inode->i_op->fileattr_get(dentry, fa);
 740}
 741EXPORT_SYMBOL(vfs_fileattr_get);
 742
 743/**
 744 * copy_fsxattr_to_user - copy fsxattr to userspace.
 745 * @fa:         fileattr pointer
 746 * @ufa:        fsxattr user pointer
 747 *
 748 * Return: 0 on success, or -EFAULT on failure.
 749 */
 750int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa)
 751{
 752        struct fsxattr xfa;
 753
 754        memset(&xfa, 0, sizeof(xfa));
 755        xfa.fsx_xflags = fa->fsx_xflags;
 756        xfa.fsx_extsize = fa->fsx_extsize;
 757        xfa.fsx_nextents = fa->fsx_nextents;
 758        xfa.fsx_projid = fa->fsx_projid;
 759        xfa.fsx_cowextsize = fa->fsx_cowextsize;
 760
 761        if (copy_to_user(ufa, &xfa, sizeof(xfa)))
 762                return -EFAULT;
 763
 764        return 0;
 765}
 766EXPORT_SYMBOL(copy_fsxattr_to_user);
 767
 768static int copy_fsxattr_from_user(struct fileattr *fa,
 769                                  struct fsxattr __user *ufa)
 770{
 771        struct fsxattr xfa;
 772
 773        if (copy_from_user(&xfa, ufa, sizeof(xfa)))
 774                return -EFAULT;
 775
 776        fileattr_fill_xflags(fa, xfa.fsx_xflags);
 777        fa->fsx_extsize = xfa.fsx_extsize;
 778        fa->fsx_nextents = xfa.fsx_nextents;
 779        fa->fsx_projid = xfa.fsx_projid;
 780        fa->fsx_cowextsize = xfa.fsx_cowextsize;
 781
 782        return 0;
 783}
 784
 785/*
 786 * Generic function to check FS_IOC_FSSETXATTR/FS_IOC_SETFLAGS values and reject
 787 * any invalid configurations.
 788 *
 789 * Note: must be called with inode lock held.
 790 */
 791static int fileattr_set_prepare(struct inode *inode,
 792                              const struct fileattr *old_ma,
 793                              struct fileattr *fa)
 794{
 795        int err;
 796
 797        /*
 798         * The IMMUTABLE and APPEND_ONLY flags can only be changed by
 799         * the relevant capability.
 800         */
 801        if ((fa->flags ^ old_ma->flags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
 802            !capable(CAP_LINUX_IMMUTABLE))
 803                return -EPERM;
 804
 805        err = fscrypt_prepare_setflags(inode, old_ma->flags, fa->flags);
 806        if (err)
 807                return err;
 808
 809        /*
 810         * Project Quota ID state is only allowed to change from within the init
 811         * namespace. Enforce that restriction only if we are trying to change
 812         * the quota ID state. Everything else is allowed in user namespaces.
 813         */
 814        if (current_user_ns() != &init_user_ns) {
 815                if (old_ma->fsx_projid != fa->fsx_projid)
 816                        return -EINVAL;
 817                if ((old_ma->fsx_xflags ^ fa->fsx_xflags) &
 818                                FS_XFLAG_PROJINHERIT)
 819                        return -EINVAL;
 820        }
 821
 822        /* Check extent size hints. */
 823        if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(inode->i_mode))
 824                return -EINVAL;
 825
 826        if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
 827                        !S_ISDIR(inode->i_mode))
 828                return -EINVAL;
 829
 830        if ((fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) &&
 831            !S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
 832                return -EINVAL;
 833
 834        /*
 835         * It is only valid to set the DAX flag on regular files and
 836         * directories on filesystems.
 837         */
 838        if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
 839            !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 840                return -EINVAL;
 841
 842        /* Extent size hints of zero turn off the flags. */
 843        if (fa->fsx_extsize == 0)
 844                fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);
 845        if (fa->fsx_cowextsize == 0)
 846                fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
 847
 848        return 0;
 849}
 850
 851/**
 852 * vfs_fileattr_set - change miscellaneous file attributes
 853 * @mnt_userns: user namespace of the mount
 854 * @dentry:     the object to change
 855 * @fa:         fileattr pointer
 856 *
 857 * After verifying permissions, call i_op->fileattr_set() callback, if
 858 * exists.
 859 *
 860 * Verifying attributes involves retrieving current attributes with
 861 * i_op->fileattr_get(), this also allows initializing attributes that have
 862 * not been set by the caller to current values.  Inode lock is held
 863 * thoughout to prevent racing with another instance.
 864 *
 865 * Return: 0 on success, or a negative error on failure.
 866 */
 867int vfs_fileattr_set(struct user_namespace *mnt_userns, struct dentry *dentry,
 868                     struct fileattr *fa)
 869{
 870        struct inode *inode = d_inode(dentry);
 871        struct fileattr old_ma = {};
 872        int err;
 873
 874        if (!inode->i_op->fileattr_set)
 875                return -ENOIOCTLCMD;
 876
 877        if (!inode_owner_or_capable(mnt_userns, inode))
 878                return -EPERM;
 879
 880        inode_lock(inode);
 881        err = vfs_fileattr_get(dentry, &old_ma);
 882        if (!err) {
 883                /* initialize missing bits from old_ma */
 884                if (fa->flags_valid) {
 885                        fa->fsx_xflags |= old_ma.fsx_xflags & ~FS_XFLAG_COMMON;
 886                        fa->fsx_extsize = old_ma.fsx_extsize;
 887                        fa->fsx_nextents = old_ma.fsx_nextents;
 888                        fa->fsx_projid = old_ma.fsx_projid;
 889                        fa->fsx_cowextsize = old_ma.fsx_cowextsize;
 890                } else {
 891                        fa->flags |= old_ma.flags & ~FS_COMMON_FL;
 892                }
 893                err = fileattr_set_prepare(inode, &old_ma, fa);
 894                if (!err)
 895                        err = inode->i_op->fileattr_set(mnt_userns, dentry, fa);
 896        }
 897        inode_unlock(inode);
 898
 899        return err;
 900}
 901EXPORT_SYMBOL(vfs_fileattr_set);
 902
 903static int ioctl_getflags(struct file *file, unsigned int __user *argp)
 904{
 905        struct fileattr fa = { .flags_valid = true }; /* hint only */
 906        int err;
 907
 908        err = vfs_fileattr_get(file->f_path.dentry, &fa);
 909        if (!err)
 910                err = put_user(fa.flags, argp);
 911        return err;
 912}
 913
 914static int ioctl_setflags(struct file *file, unsigned int __user *argp)
 915{
 916        struct user_namespace *mnt_userns = file_mnt_user_ns(file);
 917        struct dentry *dentry = file->f_path.dentry;
 918        struct fileattr fa;
 919        unsigned int flags;
 920        int err;
 921
 922        err = get_user(flags, argp);
 923        if (!err) {
 924                err = mnt_want_write_file(file);
 925                if (!err) {
 926                        fileattr_fill_flags(&fa, flags);
 927                        err = vfs_fileattr_set(mnt_userns, dentry, &fa);
 928                        mnt_drop_write_file(file);
 929                }
 930        }
 931        return err;
 932}
 933
 934static int ioctl_fsgetxattr(struct file *file, void __user *argp)
 935{
 936        struct fileattr fa = { .fsx_valid = true }; /* hint only */
 937        int err;
 938
 939        err = vfs_fileattr_get(file->f_path.dentry, &fa);
 940        if (!err)
 941                err = copy_fsxattr_to_user(&fa, argp);
 942
 943        return err;
 944}
 945
 946static int ioctl_fssetxattr(struct file *file, void __user *argp)
 947{
 948        struct user_namespace *mnt_userns = file_mnt_user_ns(file);
 949        struct dentry *dentry = file->f_path.dentry;
 950        struct fileattr fa;
 951        int err;
 952
 953        err = copy_fsxattr_from_user(&fa, argp);
 954        if (!err) {
 955                err = mnt_want_write_file(file);
 956                if (!err) {
 957                        err = vfs_fileattr_set(mnt_userns, dentry, &fa);
 958                        mnt_drop_write_file(file);
 959                }
 960        }
 961        return err;
 962}
 963
 964/*
 965 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
 966 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
 967 *
 968 * When you add any new common ioctls to the switches above and below,
 969 * please ensure they have compatible arguments in compat mode.
 970 */
 971static int do_vfs_ioctl(struct file *filp, unsigned int fd,
 972                        unsigned int cmd, unsigned long arg)
 973{
 974        void __user *argp = (void __user *)arg;
 975        struct inode *inode = file_inode(filp);
 976
 977        switch (cmd) {
 978        case FIOCLEX:
 979                set_close_on_exec(fd, 1);
 980                return 0;
 981
 982        case FIONCLEX:
 983                set_close_on_exec(fd, 0);
 984                return 0;
 985
 986        case FIONBIO:
 987                return ioctl_fionbio(filp, argp);
 988
 989        case FIOASYNC:
 990                return ioctl_fioasync(fd, filp, argp);
 991
 992        case FIOQSIZE:
 993                if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
 994                    S_ISLNK(inode->i_mode)) {
 995                        loff_t res = inode_get_bytes(inode);
 996                        return copy_to_user(argp, &res, sizeof(res)) ?
 997                                            -EFAULT : 0;
 998                }
 999
1000                return -ENOTTY;
1001
1002        case FIFREEZE:
1003                return ioctl_fsfreeze(filp);
1004
1005        case FITHAW:
1006                return ioctl_fsthaw(filp);
1007
1008        case FS_IOC_FIEMAP:
1009                return ioctl_fiemap(filp, argp);
1010
1011        case FIGETBSZ:
1012                /* anon_bdev filesystems may not have a block size */
1013                if (!inode->i_sb->s_blocksize)
1014                        return -EINVAL;
1015
1016                return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
1017
1018        case FICLONE:
1019                return ioctl_file_clone(filp, arg, 0, 0, 0);
1020
1021        case FICLONERANGE:
1022                return ioctl_file_clone_range(filp, argp);
1023
1024        case FIDEDUPERANGE:
1025                return ioctl_file_dedupe_range(filp, argp);
1026
1027        case FIONREAD:
1028                if (!S_ISREG(inode->i_mode))
1029                        return vfs_ioctl(filp, cmd, arg);
1030
1031                return put_user(i_size_read(inode) - filp->f_pos,
1032                                (int __user *)argp);
1033
1034        case FS_IOC_GETFLAGS:
1035                return ioctl_getflags(filp, argp);
1036
1037        case FS_IOC_SETFLAGS:
1038                return ioctl_setflags(filp, argp);
1039
1040        case FS_IOC_FSGETXATTR:
1041                return ioctl_fsgetxattr(filp, argp);
1042
1043        case FS_IOC_FSSETXATTR:
1044                return ioctl_fssetxattr(filp, argp);
1045
1046        default:
1047                if (S_ISREG(inode->i_mode))
1048                        return file_ioctl(filp, cmd, argp);
1049                break;
1050        }
1051
1052        return -ENOIOCTLCMD;
1053}
1054
1055SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
1056{
1057        struct fd f = fdget(fd);
1058        int error;
1059
1060        if (!f.file)
1061                return -EBADF;
1062
1063        error = security_file_ioctl(f.file, cmd, arg);
1064        if (error)
1065                goto out;
1066
1067        error = do_vfs_ioctl(f.file, fd, cmd, arg);
1068        if (error == -ENOIOCTLCMD)
1069                error = vfs_ioctl(f.file, cmd, arg);
1070
1071out:
1072        fdput(f);
1073        return error;
1074}
1075
1076#ifdef CONFIG_COMPAT
1077/**
1078 * compat_ptr_ioctl - generic implementation of .compat_ioctl file operation
1079 *
1080 * This is not normally called as a function, but instead set in struct
1081 * file_operations as
1082 *
1083 *     .compat_ioctl = compat_ptr_ioctl,
1084 *
1085 * On most architectures, the compat_ptr_ioctl() just passes all arguments
1086 * to the corresponding ->ioctl handler. The exception is arch/s390, where
1087 * compat_ptr() clears the top bit of a 32-bit pointer value, so user space
1088 * pointers to the second 2GB alias the first 2GB, as is the case for
1089 * native 32-bit s390 user space.
1090 *
1091 * The compat_ptr_ioctl() function must therefore be used only with ioctl
1092 * functions that either ignore the argument or pass a pointer to a
1093 * compatible data type.
1094 *
1095 * If any ioctl command handled by fops->unlocked_ioctl passes a plain
1096 * integer instead of a pointer, or any of the passed data types
1097 * is incompatible between 32-bit and 64-bit architectures, a proper
1098 * handler is required instead of compat_ptr_ioctl.
1099 */
1100long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1101{
1102        if (!file->f_op->unlocked_ioctl)
1103                return -ENOIOCTLCMD;
1104
1105        return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
1106}
1107EXPORT_SYMBOL(compat_ptr_ioctl);
1108
1109COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
1110                       compat_ulong_t, arg)
1111{
1112        struct fd f = fdget(fd);
1113        int error;
1114
1115        if (!f.file)
1116                return -EBADF;
1117
1118        /* RED-PEN how should LSM module know it's handling 32bit? */
1119        error = security_file_ioctl(f.file, cmd, arg);
1120        if (error)
1121                goto out;
1122
1123        switch (cmd) {
1124        /* FICLONE takes an int argument, so don't use compat_ptr() */
1125        case FICLONE:
1126                error = ioctl_file_clone(f.file, arg, 0, 0, 0);
1127                break;
1128
1129#if defined(CONFIG_X86_64)
1130        /* these get messy on amd64 due to alignment differences */
1131        case FS_IOC_RESVSP_32:
1132        case FS_IOC_RESVSP64_32:
1133                error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
1134                break;
1135        case FS_IOC_UNRESVSP_32:
1136        case FS_IOC_UNRESVSP64_32:
1137                error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
1138                                compat_ptr(arg));
1139                break;
1140        case FS_IOC_ZERO_RANGE_32:
1141                error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
1142                                compat_ptr(arg));
1143                break;
1144#endif
1145
1146        /*
1147         * These access 32-bit values anyway so no further handling is
1148         * necessary.
1149         */
1150        case FS_IOC32_GETFLAGS:
1151        case FS_IOC32_SETFLAGS:
1152                cmd = (cmd == FS_IOC32_GETFLAGS) ?
1153                        FS_IOC_GETFLAGS : FS_IOC_SETFLAGS;
1154                fallthrough;
1155        /*
1156         * everything else in do_vfs_ioctl() takes either a compatible
1157         * pointer argument or no argument -- call it with a modified
1158         * argument.
1159         */
1160        default:
1161                error = do_vfs_ioctl(f.file, fd, cmd,
1162                                     (unsigned long)compat_ptr(arg));
1163                if (error != -ENOIOCTLCMD)
1164                        break;
1165
1166                if (f.file->f_op->compat_ioctl)
1167                        error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
1168                if (error == -ENOIOCTLCMD)
1169                        error = -ENOTTY;
1170                break;
1171        }
1172
1173 out:
1174        fdput(f);
1175
1176        return error;
1177}
1178#endif
1179
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