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fs/ioctl.c 24 KB
b24413180   Greg Kroah-Hartman   License cleanup: ...
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  // SPDX-License-Identifier: GPL-2.0
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  /*
   *  linux/fs/ioctl.c
   *
   *  Copyright (C) 1991, 1992  Linus Torvalds
   */
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  #include <linux/syscalls.h>
  #include <linux/mm.h>
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  #include <linux/capability.h>
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  #include <linux/compat.h>
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  #include <linux/file.h>
  #include <linux/fs.h>
  #include <linux/security.h>
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  #include <linux/export.h>
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  #include <linux/uaccess.h>
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  #include <linux/writeback.h>
  #include <linux/buffer_head.h>
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  #include <linux/falloc.h>
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  #include <linux/sched/signal.h>
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  #include <linux/fiemap.h>
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  #include <linux/mount.h>
  #include <linux/fscrypt.h>
  #include <linux/fileattr.h>
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  #include "internal.h"
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
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  #include <asm/ioctls.h>
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  /* So that the fiemap access checks can't overflow on 32 bit machines. */
  #define FIEMAP_MAX_EXTENTS	(UINT_MAX / sizeof(struct fiemap_extent))
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  /**
   * vfs_ioctl - call filesystem specific ioctl methods
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   * @filp:	open file to invoke ioctl method on
   * @cmd:	ioctl command to execute
   * @arg:	command-specific argument for ioctl
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   *
   * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
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   * returns -ENOTTY.
   *
   * Returns 0 on success, -errno on error.
   */
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  long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
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  {
  	int error = -ENOTTY;
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  	if (!filp->f_op->unlocked_ioctl)
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  		goto out;
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  	error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
  	if (error == -ENOIOCTLCMD)
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  		error = -ENOTTY;
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   out:
  	return error;
  }
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  EXPORT_SYMBOL(vfs_ioctl);
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  static int ioctl_fibmap(struct file *filp, int __user *p)
  {
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  	struct inode *inode = file_inode(filp);
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  	struct super_block *sb = inode->i_sb;
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  	int error, ur_block;
  	sector_t block;
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  	if (!capable(CAP_SYS_RAWIO))
  		return -EPERM;
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  	error = get_user(ur_block, p);
  	if (error)
  		return error;
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  	if (ur_block < 0)
  		return -EINVAL;
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  	block = ur_block;
  	error = bmap(inode, &block);
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  	if (block > INT_MAX) {
  		error = -ERANGE;
  		pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result
  ",
  				    current->comm, task_pid_nr(current),
  				    sb->s_id, filp);
  	}
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  	if (error)
  		ur_block = 0;
  	else
  		ur_block = block;
  
  	if (put_user(ur_block, p))
  		error = -EFAULT;
  
  	return error;
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  }
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  /**
   * fiemap_fill_next_extent - Fiemap helper function
   * @fieinfo:	Fiemap context passed into ->fiemap
   * @logical:	Extent logical start offset, in bytes
   * @phys:	Extent physical start offset, in bytes
   * @len:	Extent length, in bytes
   * @flags:	FIEMAP_EXTENT flags that describe this extent
   *
   * Called from file system ->fiemap callback. Will populate extent
   * info as passed in via arguments and copy to user memory. On
   * success, extent count on fieinfo is incremented.
   *
   * Returns 0 on success, -errno on error, 1 if this was the last
   * extent that will fit in user array.
   */
  #define SET_UNKNOWN_FLAGS	(FIEMAP_EXTENT_DELALLOC)
  #define SET_NO_UNMOUNTED_IO_FLAGS	(FIEMAP_EXTENT_DATA_ENCRYPTED)
  #define SET_NOT_ALIGNED_FLAGS	(FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
  int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
  			    u64 phys, u64 len, u32 flags)
  {
  	struct fiemap_extent extent;
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  	struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
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  	/* only count the extents */
  	if (fieinfo->fi_extents_max == 0) {
  		fieinfo->fi_extents_mapped++;
  		return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
  	}
  
  	if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
  		return 1;
  
  	if (flags & SET_UNKNOWN_FLAGS)
  		flags |= FIEMAP_EXTENT_UNKNOWN;
  	if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
  		flags |= FIEMAP_EXTENT_ENCODED;
  	if (flags & SET_NOT_ALIGNED_FLAGS)
  		flags |= FIEMAP_EXTENT_NOT_ALIGNED;
  
  	memset(&extent, 0, sizeof(extent));
  	extent.fe_logical = logical;
  	extent.fe_physical = phys;
  	extent.fe_length = len;
  	extent.fe_flags = flags;
  
  	dest += fieinfo->fi_extents_mapped;
  	if (copy_to_user(dest, &extent, sizeof(extent)))
  		return -EFAULT;
  
  	fieinfo->fi_extents_mapped++;
  	if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
  		return 1;
  	return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
  }
  EXPORT_SYMBOL(fiemap_fill_next_extent);
  
  /**
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   * fiemap_prep - check validity of requested flags for fiemap
   * @inode:	Inode to operate on
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   * @fieinfo:	Fiemap context passed into ->fiemap
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   * @start:	Start of the mapped range
   * @len:	Length of the mapped range, can be truncated by this function.
   * @supported_flags:	Set of fiemap flags that the file system understands
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   *
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   * This function must be called from each ->fiemap instance to validate the
   * fiemap request against the file system parameters.
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   *
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   * Returns 0 on success, or a negative error on failure.
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   */
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  int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
  		u64 start, u64 *len, u32 supported_flags)
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  {
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  	u64 maxbytes = inode->i_sb->s_maxbytes;
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  	u32 incompat_flags;
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  	int ret = 0;
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  	if (*len == 0)
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  		return -EINVAL;
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  	if (start >= maxbytes)
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  		return -EFBIG;
  
  	/*
  	 * Shrink request scope to what the fs can actually handle.
  	 */
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  	if (*len > maxbytes || (maxbytes - *len) < start)
  		*len = maxbytes - start;
c4b929b85   Mark Fasheh   vfs: vfs-level fi...
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  	supported_flags |= FIEMAP_FLAG_SYNC;
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  	supported_flags &= FIEMAP_FLAGS_COMPAT;
  	incompat_flags = fieinfo->fi_flags & ~supported_flags;
  	if (incompat_flags) {
  		fieinfo->fi_flags = incompat_flags;
  		return -EBADR;
  	}
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  	if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
  		ret = filemap_write_and_wait(inode->i_mapping);
  	return ret;
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  }
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  EXPORT_SYMBOL(fiemap_prep);
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  static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap)
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  {
  	struct fiemap fiemap;
  	struct fiemap_extent_info fieinfo = { 0, };
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  	struct inode *inode = file_inode(filp);
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  	int error;
  
  	if (!inode->i_op->fiemap)
  		return -EOPNOTSUPP;
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  	if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
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  		return -EFAULT;
  
  	if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
  		return -EINVAL;
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  	fieinfo.fi_flags = fiemap.fm_flags;
  	fieinfo.fi_extents_max = fiemap.fm_extent_count;
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  	fieinfo.fi_extents_start = ufiemap->fm_extents;
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  	error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start,
  			fiemap.fm_length);
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  	fiemap.fm_flags = fieinfo.fi_flags;
  	fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
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  	if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
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  		error = -EFAULT;
  
  	return error;
  }
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  static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
  			     u64 off, u64 olen, u64 destoff)
  {
  	struct fd src_file = fdget(srcfd);
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  	loff_t cloned;
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  	int ret;
  
  	if (!src_file.file)
  		return -EBADF;
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  	ret = -EXDEV;
  	if (src_file.file->f_path.mnt != dst_file->f_path.mnt)
  		goto fdput;
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  	cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff,
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  				      olen, 0);
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  	if (cloned < 0)
  		ret = cloned;
  	else if (olen && cloned != olen)
  		ret = -EINVAL;
  	else
  		ret = 0;
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  fdput:
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  	fdput(src_file);
  	return ret;
  }
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  static long ioctl_file_clone_range(struct file *file,
  				   struct file_clone_range __user *argp)
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  {
  	struct file_clone_range args;
  
  	if (copy_from_user(&args, argp, sizeof(args)))
  		return -EFAULT;
  	return ioctl_file_clone(file, args.src_fd, args.src_offset,
  				args.src_length, args.dest_offset);
  }
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  /*
   * This provides compatibility with legacy XFS pre-allocation ioctls
   * which predate the fallocate syscall.
   *
   * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
   * are used here, rest are ignored.
   */
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  static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
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  {
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  	struct inode *inode = file_inode(filp);
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  	struct space_resv sr;
  
  	if (copy_from_user(&sr, argp, sizeof(sr)))
  		return -EFAULT;
  
  	switch (sr.l_whence) {
  	case SEEK_SET:
  		break;
  	case SEEK_CUR:
  		sr.l_start += filp->f_pos;
  		break;
  	case SEEK_END:
  		sr.l_start += i_size_read(inode);
  		break;
  	default:
  		return -EINVAL;
  	}
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  	return vfs_fallocate(filp, mode | FALLOC_FL_KEEP_SIZE, sr.l_start,
  			sr.l_len);
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  }
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  /* on ia32 l_start is on a 32-bit boundary */
  #if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
  /* just account for different alignment */
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  static int compat_ioctl_preallocate(struct file *file, int mode,
  				    struct space_resv_32 __user *argp)
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  {
  	struct inode *inode = file_inode(file);
  	struct space_resv_32 sr;
  
  	if (copy_from_user(&sr, argp, sizeof(sr)))
  		return -EFAULT;
  
  	switch (sr.l_whence) {
  	case SEEK_SET:
  		break;
  	case SEEK_CUR:
  		sr.l_start += file->f_pos;
  		break;
  	case SEEK_END:
  		sr.l_start += i_size_read(inode);
  		break;
  	default:
  		return -EINVAL;
  	}
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  	return vfs_fallocate(file, mode | FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
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  }
  #endif
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  static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
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  {
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  	switch (cmd) {
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  	case FIBMAP:
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  		return ioctl_fibmap(filp, p);
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  	case FS_IOC_RESVSP:
  	case FS_IOC_RESVSP64:
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  		return ioctl_preallocate(filp, 0, p);
  	case FS_IOC_UNRESVSP:
  	case FS_IOC_UNRESVSP64:
  		return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, p);
  	case FS_IOC_ZERO_RANGE:
  		return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, p);
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  	}
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  	return -ENOIOCTLCMD;
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  }
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  static int ioctl_fionbio(struct file *filp, int __user *argp)
  {
  	unsigned int flag;
  	int on, error;
  
  	error = get_user(on, argp);
  	if (error)
  		return error;
  	flag = O_NONBLOCK;
  #ifdef __sparc__
  	/* SunOS compatibility item. */
  	if (O_NONBLOCK != O_NDELAY)
  		flag |= O_NDELAY;
  #endif
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  	spin_lock(&filp->f_lock);
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  	if (on)
  		filp->f_flags |= flag;
  	else
  		filp->f_flags &= ~flag;
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  	spin_unlock(&filp->f_lock);
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  	return error;
  }
  
  static int ioctl_fioasync(unsigned int fd, struct file *filp,
  			  int __user *argp)
  {
  	unsigned int flag;
  	int on, error;
  
  	error = get_user(on, argp);
  	if (error)
  		return error;
  	flag = on ? FASYNC : 0;
  
  	/* Did FASYNC state change ? */
  	if ((flag ^ filp->f_flags) & FASYNC) {
72c2d5319   Al Viro   file->f_op is nev...
361
  		if (filp->f_op->fasync)
76398425b   Jonathan Corbet   Move FASYNC bit h...
362
  			/* fasync() adjusts filp->f_flags */
aa81a7c71   Erez Zadok   VFS: factor out t...
363
  			error = filp->f_op->fasync(fd, filp, on);
218d11a8b   Jonathan Corbet   Fix a race condit...
364
  		else
aa81a7c71   Erez Zadok   VFS: factor out t...
365
366
  			error = -ENOTTY;
  	}
60aa49243   Jonathan Corbet   Rationalize fasyn...
367
  	return error < 0 ? error : 0;
aa81a7c71   Erez Zadok   VFS: factor out t...
368
  }
fcccf5025   Takashi Sato   filesystem freeze...
369
370
  static int ioctl_fsfreeze(struct file *filp)
  {
496ad9aa8   Al Viro   new helper: file_...
371
  	struct super_block *sb = file_inode(filp)->i_sb;
fcccf5025   Takashi Sato   filesystem freeze...
372

f3f1a1833   Seth Forshee   fs: Allow CAP_SYS...
373
  	if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
fcccf5025   Takashi Sato   filesystem freeze...
374
375
376
  		return -EPERM;
  
  	/* If filesystem doesn't support freeze feature, return. */
48b6bca6b   Benjamin Marzinski   fs: add freeze_su...
377
  	if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
fcccf5025   Takashi Sato   filesystem freeze...
378
  		return -EOPNOTSUPP;
fcccf5025   Takashi Sato   filesystem freeze...
379
  	/* Freeze */
48b6bca6b   Benjamin Marzinski   fs: add freeze_su...
380
381
  	if (sb->s_op->freeze_super)
  		return sb->s_op->freeze_super(sb);
18e9e5104   Josef Bacik   Introduce freeze_...
382
  	return freeze_super(sb);
fcccf5025   Takashi Sato   filesystem freeze...
383
384
385
386
  }
  
  static int ioctl_fsthaw(struct file *filp)
  {
496ad9aa8   Al Viro   new helper: file_...
387
  	struct super_block *sb = file_inode(filp)->i_sb;
fcccf5025   Takashi Sato   filesystem freeze...
388

f3f1a1833   Seth Forshee   fs: Allow CAP_SYS...
389
  	if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
fcccf5025   Takashi Sato   filesystem freeze...
390
  		return -EPERM;
fcccf5025   Takashi Sato   filesystem freeze...
391
  	/* Thaw */
48b6bca6b   Benjamin Marzinski   fs: add freeze_su...
392
393
  	if (sb->s_op->thaw_super)
  		return sb->s_op->thaw_super(sb);
18e9e5104   Josef Bacik   Introduce freeze_...
394
  	return thaw_super(sb);
fcccf5025   Takashi Sato   filesystem freeze...
395
  }
34d3d0e65   Al Viro   do_vfs_ioctl(): u...
396
397
  static int ioctl_file_dedupe_range(struct file *file,
  				   struct file_dedupe_range __user *argp)
54dbc1517   Darrick J. Wong   vfs: hoist the bt...
398
  {
54dbc1517   Darrick J. Wong   vfs: hoist the bt...
399
400
401
402
403
404
405
406
407
408
409
  	struct file_dedupe_range *same = NULL;
  	int ret;
  	unsigned long size;
  	u16 count;
  
  	if (get_user(count, &argp->dest_count)) {
  		ret = -EFAULT;
  		goto out;
  	}
  
  	size = offsetof(struct file_dedupe_range __user, info[count]);
b71dbf103   Darrick J. Wong   vfs: cap dedupe r...
410
411
412
413
  	if (size > PAGE_SIZE) {
  		ret = -ENOMEM;
  		goto out;
  	}
54dbc1517   Darrick J. Wong   vfs: hoist the bt...
414
415
416
417
418
419
420
  
  	same = memdup_user(argp, size);
  	if (IS_ERR(same)) {
  		ret = PTR_ERR(same);
  		same = NULL;
  		goto out;
  	}
10eec60ce   Scott Bauer   vfs: ioctl: preve...
421
  	same->dest_count = count;
54dbc1517   Darrick J. Wong   vfs: hoist the bt...
422
423
424
425
426
427
428
429
430
431
432
433
  	ret = vfs_dedupe_file_range(file, same);
  	if (ret)
  		goto out;
  
  	ret = copy_to_user(argp, same, size);
  	if (ret)
  		ret = -EFAULT;
  
  out:
  	kfree(same);
  	return ret;
  }
4c5b47997   Miklos Szeredi   vfs: add fileattr...
434
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575
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590
  /**
   * fileattr_fill_xflags - initialize fileattr with xflags
   * @fa:		fileattr pointer
   * @xflags:	FS_XFLAG_* flags
   *
   * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags).  All
   * other fields are zeroed.
   */
  void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
  {
  	memset(fa, 0, sizeof(*fa));
  	fa->fsx_valid = true;
  	fa->fsx_xflags = xflags;
  	if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)
  		fa->flags |= FS_IMMUTABLE_FL;
  	if (fa->fsx_xflags & FS_XFLAG_APPEND)
  		fa->flags |= FS_APPEND_FL;
  	if (fa->fsx_xflags & FS_XFLAG_SYNC)
  		fa->flags |= FS_SYNC_FL;
  	if (fa->fsx_xflags & FS_XFLAG_NOATIME)
  		fa->flags |= FS_NOATIME_FL;
  	if (fa->fsx_xflags & FS_XFLAG_NODUMP)
  		fa->flags |= FS_NODUMP_FL;
  	if (fa->fsx_xflags & FS_XFLAG_DAX)
  		fa->flags |= FS_DAX_FL;
  	if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
  		fa->flags |= FS_PROJINHERIT_FL;
  }
  EXPORT_SYMBOL(fileattr_fill_xflags);
  
  /**
   * fileattr_fill_flags - initialize fileattr with flags
   * @fa:		fileattr pointer
   * @flags:	FS_*_FL flags
   *
   * Set ->flags, ->flags_valid and ->fsx_xflags (translated flags).
   * All other fields are zeroed.
   */
  void fileattr_fill_flags(struct fileattr *fa, u32 flags)
  {
  	memset(fa, 0, sizeof(*fa));
  	fa->flags_valid = true;
  	fa->flags = flags;
  	if (fa->flags & FS_SYNC_FL)
  		fa->fsx_xflags |= FS_XFLAG_SYNC;
  	if (fa->flags & FS_IMMUTABLE_FL)
  		fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
  	if (fa->flags & FS_APPEND_FL)
  		fa->fsx_xflags |= FS_XFLAG_APPEND;
  	if (fa->flags & FS_NODUMP_FL)
  		fa->fsx_xflags |= FS_XFLAG_NODUMP;
  	if (fa->flags & FS_NOATIME_FL)
  		fa->fsx_xflags |= FS_XFLAG_NOATIME;
  	if (fa->flags & FS_DAX_FL)
  		fa->fsx_xflags |= FS_XFLAG_DAX;
  	if (fa->flags & FS_PROJINHERIT_FL)
  		fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
  }
  EXPORT_SYMBOL(fileattr_fill_flags);
  
  /**
   * vfs_fileattr_get - retrieve miscellaneous file attributes
   * @dentry:	the object to retrieve from
   * @fa:		fileattr pointer
   *
   * Call i_op->fileattr_get() callback, if exists.
   *
   * Return: 0 on success, or a negative error on failure.
   */
  int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
  {
  	struct inode *inode = d_inode(dentry);
  
  	if (!inode->i_op->fileattr_get)
  		return -ENOIOCTLCMD;
  
  	return inode->i_op->fileattr_get(dentry, fa);
  }
  EXPORT_SYMBOL(vfs_fileattr_get);
  
  /**
   * copy_fsxattr_to_user - copy fsxattr to userspace.
   * @fa:		fileattr pointer
   * @ufa:	fsxattr user pointer
   *
   * Return: 0 on success, or -EFAULT on failure.
   */
  int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa)
  {
  	struct fsxattr xfa;
  
  	memset(&xfa, 0, sizeof(xfa));
  	xfa.fsx_xflags = fa->fsx_xflags;
  	xfa.fsx_extsize = fa->fsx_extsize;
  	xfa.fsx_nextents = fa->fsx_nextents;
  	xfa.fsx_projid = fa->fsx_projid;
  	xfa.fsx_cowextsize = fa->fsx_cowextsize;
  
  	if (copy_to_user(ufa, &xfa, sizeof(xfa)))
  		return -EFAULT;
  
  	return 0;
  }
  EXPORT_SYMBOL(copy_fsxattr_to_user);
  
  static int copy_fsxattr_from_user(struct fileattr *fa,
  				  struct fsxattr __user *ufa)
  {
  	struct fsxattr xfa;
  
  	if (copy_from_user(&xfa, ufa, sizeof(xfa)))
  		return -EFAULT;
  
  	fileattr_fill_xflags(fa, xfa.fsx_xflags);
  	fa->fsx_extsize = xfa.fsx_extsize;
  	fa->fsx_nextents = xfa.fsx_nextents;
  	fa->fsx_projid = xfa.fsx_projid;
  	fa->fsx_cowextsize = xfa.fsx_cowextsize;
  
  	return 0;
  }
  
  /*
   * Generic function to check FS_IOC_FSSETXATTR/FS_IOC_SETFLAGS values and reject
   * any invalid configurations.
   *
   * Note: must be called with inode lock held.
   */
  static int fileattr_set_prepare(struct inode *inode,
  			      const struct fileattr *old_ma,
  			      struct fileattr *fa)
  {
  	int err;
  
  	/*
  	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
  	 * the relevant capability.
  	 */
  	if ((fa->flags ^ old_ma->flags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
  	    !capable(CAP_LINUX_IMMUTABLE))
  		return -EPERM;
  
  	err = fscrypt_prepare_setflags(inode, old_ma->flags, fa->flags);
  	if (err)
  		return err;
  
  	/*
  	 * Project Quota ID state is only allowed to change from within the init
  	 * namespace. Enforce that restriction only if we are trying to change
  	 * the quota ID state. Everything else is allowed in user namespaces.
  	 */
  	if (current_user_ns() != &init_user_ns) {
  		if (old_ma->fsx_projid != fa->fsx_projid)
  			return -EINVAL;
  		if ((old_ma->fsx_xflags ^ fa->fsx_xflags) &
  				FS_XFLAG_PROJINHERIT)
  			return -EINVAL;
d03ef4daf   Wang Shilong   fs: forbid invali...
591
592
593
594
595
596
597
598
  	} else {
  		/*
  		 * Caller is allowed to change the project ID. If it is being
  		 * changed, make sure that the new value is valid.
  		 */
  		if (old_ma->fsx_projid != fa->fsx_projid &&
  		    !projid_valid(make_kprojid(&init_user_ns, fa->fsx_projid)))
  			return -EINVAL;
4c5b47997   Miklos Szeredi   vfs: add fileattr...
599
600
601
602
603
604
605
606
607
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609
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611
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729
730
731
732
733
734
735
736
737
738
739
740
741
  	}
  
  	/* Check extent size hints. */
  	if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(inode->i_mode))
  		return -EINVAL;
  
  	if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
  			!S_ISDIR(inode->i_mode))
  		return -EINVAL;
  
  	if ((fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) &&
  	    !S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
  		return -EINVAL;
  
  	/*
  	 * It is only valid to set the DAX flag on regular files and
  	 * directories on filesystems.
  	 */
  	if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
  	    !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
  		return -EINVAL;
  
  	/* Extent size hints of zero turn off the flags. */
  	if (fa->fsx_extsize == 0)
  		fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);
  	if (fa->fsx_cowextsize == 0)
  		fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
  
  	return 0;
  }
  
  /**
   * vfs_fileattr_set - change miscellaneous file attributes
   * @mnt_userns:	user namespace of the mount
   * @dentry:	the object to change
   * @fa:		fileattr pointer
   *
   * After verifying permissions, call i_op->fileattr_set() callback, if
   * exists.
   *
   * Verifying attributes involves retrieving current attributes with
   * i_op->fileattr_get(), this also allows initializing attributes that have
   * not been set by the caller to current values.  Inode lock is held
   * thoughout to prevent racing with another instance.
   *
   * Return: 0 on success, or a negative error on failure.
   */
  int vfs_fileattr_set(struct user_namespace *mnt_userns, struct dentry *dentry,
  		     struct fileattr *fa)
  {
  	struct inode *inode = d_inode(dentry);
  	struct fileattr old_ma = {};
  	int err;
  
  	if (!inode->i_op->fileattr_set)
  		return -ENOIOCTLCMD;
  
  	if (!inode_owner_or_capable(mnt_userns, inode))
  		return -EPERM;
  
  	inode_lock(inode);
  	err = vfs_fileattr_get(dentry, &old_ma);
  	if (!err) {
  		/* initialize missing bits from old_ma */
  		if (fa->flags_valid) {
  			fa->fsx_xflags |= old_ma.fsx_xflags & ~FS_XFLAG_COMMON;
  			fa->fsx_extsize = old_ma.fsx_extsize;
  			fa->fsx_nextents = old_ma.fsx_nextents;
  			fa->fsx_projid = old_ma.fsx_projid;
  			fa->fsx_cowextsize = old_ma.fsx_cowextsize;
  		} else {
  			fa->flags |= old_ma.flags & ~FS_COMMON_FL;
  		}
  		err = fileattr_set_prepare(inode, &old_ma, fa);
  		if (!err)
  			err = inode->i_op->fileattr_set(mnt_userns, dentry, fa);
  	}
  	inode_unlock(inode);
  
  	return err;
  }
  EXPORT_SYMBOL(vfs_fileattr_set);
  
  static int ioctl_getflags(struct file *file, unsigned int __user *argp)
  {
  	struct fileattr fa = { .flags_valid = true }; /* hint only */
  	int err;
  
  	err = vfs_fileattr_get(file->f_path.dentry, &fa);
  	if (!err)
  		err = put_user(fa.flags, argp);
  	return err;
  }
  
  static int ioctl_setflags(struct file *file, unsigned int __user *argp)
  {
  	struct user_namespace *mnt_userns = file_mnt_user_ns(file);
  	struct dentry *dentry = file->f_path.dentry;
  	struct fileattr fa;
  	unsigned int flags;
  	int err;
  
  	err = get_user(flags, argp);
  	if (!err) {
  		err = mnt_want_write_file(file);
  		if (!err) {
  			fileattr_fill_flags(&fa, flags);
  			err = vfs_fileattr_set(mnt_userns, dentry, &fa);
  			mnt_drop_write_file(file);
  		}
  	}
  	return err;
  }
  
  static int ioctl_fsgetxattr(struct file *file, void __user *argp)
  {
  	struct fileattr fa = { .fsx_valid = true }; /* hint only */
  	int err;
  
  	err = vfs_fileattr_get(file->f_path.dentry, &fa);
  	if (!err)
  		err = copy_fsxattr_to_user(&fa, argp);
  
  	return err;
  }
  
  static int ioctl_fssetxattr(struct file *file, void __user *argp)
  {
  	struct user_namespace *mnt_userns = file_mnt_user_ns(file);
  	struct dentry *dentry = file->f_path.dentry;
  	struct fileattr fa;
  	int err;
  
  	err = copy_fsxattr_from_user(&fa, argp);
  	if (!err) {
  		err = mnt_want_write_file(file);
  		if (!err) {
  			err = vfs_fileattr_set(mnt_userns, dentry, &fa);
  			mnt_drop_write_file(file);
  		}
  	}
  	return err;
  }
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
742
  /*
deb21db77   Erez Zadok   VFS: swap do_ioct...
743
   * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
744
   * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
77b904019   Arnd Bergmann   compat_ioctl: sim...
745
746
747
   *
   * When you add any new common ioctls to the switches above and below,
   * please ensure they have compatible arguments in compat mode.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
748
   */
77b904019   Arnd Bergmann   compat_ioctl: sim...
749
750
  static int do_vfs_ioctl(struct file *filp, unsigned int fd,
  			unsigned int cmd, unsigned long arg)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
751
  {
34d3d0e65   Al Viro   do_vfs_ioctl(): u...
752
  	void __user *argp = (void __user *)arg;
496ad9aa8   Al Viro   new helper: file_...
753
  	struct inode *inode = file_inode(filp);
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
754
755
  
  	switch (cmd) {
c9845ff1d   Erez Zadok   VFS: apply coding...
756
757
  	case FIOCLEX:
  		set_close_on_exec(fd, 1);
77b904019   Arnd Bergmann   compat_ioctl: sim...
758
  		return 0;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
759

c9845ff1d   Erez Zadok   VFS: apply coding...
760
761
  	case FIONCLEX:
  		set_close_on_exec(fd, 0);
77b904019   Arnd Bergmann   compat_ioctl: sim...
762
  		return 0;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
763

c9845ff1d   Erez Zadok   VFS: apply coding...
764
  	case FIONBIO:
77b904019   Arnd Bergmann   compat_ioctl: sim...
765
  		return ioctl_fionbio(filp, argp);
c9845ff1d   Erez Zadok   VFS: apply coding...
766
767
  
  	case FIOASYNC:
77b904019   Arnd Bergmann   compat_ioctl: sim...
768
  		return ioctl_fioasync(fd, filp, argp);
c9845ff1d   Erez Zadok   VFS: apply coding...
769
770
  
  	case FIOQSIZE:
27a4f7e61   Namhyung Kim   vfs: cleanup do_v...
771
772
773
  		if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
  		    S_ISLNK(inode->i_mode)) {
  			loff_t res = inode_get_bytes(inode);
77b904019   Arnd Bergmann   compat_ioctl: sim...
774
775
776
777
778
  			return copy_to_user(argp, &res, sizeof(res)) ?
  					    -EFAULT : 0;
  		}
  
  		return -ENOTTY;
fcccf5025   Takashi Sato   filesystem freeze...
779
780
  
  	case FIFREEZE:
77b904019   Arnd Bergmann   compat_ioctl: sim...
781
  		return ioctl_fsfreeze(filp);
fcccf5025   Takashi Sato   filesystem freeze...
782
783
  
  	case FITHAW:
77b904019   Arnd Bergmann   compat_ioctl: sim...
784
  		return ioctl_fsthaw(filp);
fcccf5025   Takashi Sato   filesystem freeze...
785

19ba0559f   Aneesh Kumar K.V   vfs: Enable FS_IO...
786
  	case FS_IOC_FIEMAP:
34d3d0e65   Al Viro   do_vfs_ioctl(): u...
787
  		return ioctl_fiemap(filp, argp);
19ba0559f   Aneesh Kumar K.V   vfs: Enable FS_IO...
788
789
  
  	case FIGETBSZ:
8f97d1e99   Amir Goldstein   vfs: fix FIGETBSZ...
790
791
792
  		/* anon_bdev filesystems may not have a block size */
  		if (!inode->i_sb->s_blocksize)
  			return -EINVAL;
77b904019   Arnd Bergmann   compat_ioctl: sim...
793

34d3d0e65   Al Viro   do_vfs_ioctl(): u...
794
  		return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
19ba0559f   Aneesh Kumar K.V   vfs: Enable FS_IO...
795

04b38d601   Christoph Hellwig   vfs: pull btrfs c...
796
797
798
799
800
  	case FICLONE:
  		return ioctl_file_clone(filp, arg, 0, 0, 0);
  
  	case FICLONERANGE:
  		return ioctl_file_clone_range(filp, argp);
54dbc1517   Darrick J. Wong   vfs: hoist the bt...
801
802
  	case FIDEDUPERANGE:
  		return ioctl_file_dedupe_range(filp, argp);
0a061743a   Arnd Bergmann   compat_ioctl: fix...
803
804
805
806
807
808
  	case FIONREAD:
  		if (!S_ISREG(inode->i_mode))
  			return vfs_ioctl(filp, cmd, arg);
  
  		return put_user(i_size_read(inode) - filp->f_pos,
  				(int __user *)argp);
4c5b47997   Miklos Szeredi   vfs: add fileattr...
809
810
811
812
813
814
815
816
817
818
819
  	case FS_IOC_GETFLAGS:
  		return ioctl_getflags(filp, argp);
  
  	case FS_IOC_SETFLAGS:
  		return ioctl_setflags(filp, argp);
  
  	case FS_IOC_FSGETXATTR:
  		return ioctl_fsgetxattr(filp, argp);
  
  	case FS_IOC_FSSETXATTR:
  		return ioctl_fssetxattr(filp, argp);
c9845ff1d   Erez Zadok   VFS: apply coding...
820
  	default:
27a4f7e61   Namhyung Kim   vfs: cleanup do_v...
821
  		if (S_ISREG(inode->i_mode))
77b904019   Arnd Bergmann   compat_ioctl: sim...
822
  			return file_ioctl(filp, cmd, argp);
c9845ff1d   Erez Zadok   VFS: apply coding...
823
  		break;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
824
  	}
77b904019   Arnd Bergmann   compat_ioctl: sim...
825
826
  
  	return -ENOIOCTLCMD;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
827
  }
863b67e15   Christoph Hellwig   fs: remove ksys_i...
828
  SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
829
  {
2903ff019   Al Viro   switch simple cas...
830
  	struct fd f = fdget(fd);
77b904019   Arnd Bergmann   compat_ioctl: sim...
831
  	int error;
2903ff019   Al Viro   switch simple cas...
832
833
834
  
  	if (!f.file)
  		return -EBADF;
77b904019   Arnd Bergmann   compat_ioctl: sim...
835

2903ff019   Al Viro   switch simple cas...
836
  	error = security_file_ioctl(f.file, cmd, arg);
77b904019   Arnd Bergmann   compat_ioctl: sim...
837
838
839
840
841
842
843
844
  	if (error)
  		goto out;
  
  	error = do_vfs_ioctl(f.file, fd, cmd, arg);
  	if (error == -ENOIOCTLCMD)
  		error = vfs_ioctl(f.file, cmd, arg);
  
  out:
2903ff019   Al Viro   switch simple cas...
845
  	fdput(f);
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
846
847
  	return error;
  }
cbb60b924   Dominik Brodowski   fs: add ksys_ioct...
848

2952db0fd   Arnd Bergmann   compat_ioctl: add...
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
  #ifdef CONFIG_COMPAT
  /**
   * compat_ptr_ioctl - generic implementation of .compat_ioctl file operation
   *
   * This is not normally called as a function, but instead set in struct
   * file_operations as
   *
   *     .compat_ioctl = compat_ptr_ioctl,
   *
   * On most architectures, the compat_ptr_ioctl() just passes all arguments
   * to the corresponding ->ioctl handler. The exception is arch/s390, where
   * compat_ptr() clears the top bit of a 32-bit pointer value, so user space
   * pointers to the second 2GB alias the first 2GB, as is the case for
   * native 32-bit s390 user space.
   *
   * The compat_ptr_ioctl() function must therefore be used only with ioctl
   * functions that either ignore the argument or pass a pointer to a
   * compatible data type.
   *
   * If any ioctl command handled by fops->unlocked_ioctl passes a plain
   * integer instead of a pointer, or any of the passed data types
   * is incompatible between 32-bit and 64-bit architectures, a proper
   * handler is required instead of compat_ptr_ioctl.
   */
  long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
  {
  	if (!file->f_op->unlocked_ioctl)
  		return -ENOIOCTLCMD;
  
  	return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
  }
  EXPORT_SYMBOL(compat_ptr_ioctl);
2af563d07   Arnd Bergmann   compat_ioctl: mov...
881
882
  
  COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
77b904019   Arnd Bergmann   compat_ioctl: sim...
883
  		       compat_ulong_t, arg)
2af563d07   Arnd Bergmann   compat_ioctl: mov...
884
  {
2af563d07   Arnd Bergmann   compat_ioctl: mov...
885
  	struct fd f = fdget(fd);
77b904019   Arnd Bergmann   compat_ioctl: sim...
886
  	int error;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
887
  	if (!f.file)
77b904019   Arnd Bergmann   compat_ioctl: sim...
888
  		return -EBADF;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
889
890
891
892
  
  	/* RED-PEN how should LSM module know it's handling 32bit? */
  	error = security_file_ioctl(f.file, cmd, arg);
  	if (error)
77b904019   Arnd Bergmann   compat_ioctl: sim...
893
  		goto out;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
894
895
  
  	switch (cmd) {
77b904019   Arnd Bergmann   compat_ioctl: sim...
896
  	/* FICLONE takes an int argument, so don't use compat_ptr() */
2af563d07   Arnd Bergmann   compat_ioctl: mov...
897
  	case FICLONE:
77b904019   Arnd Bergmann   compat_ioctl: sim...
898
899
  		error = ioctl_file_clone(f.file, arg, 0, 0, 0);
  		break;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
900
  #if defined(CONFIG_X86_64)
77b904019   Arnd Bergmann   compat_ioctl: sim...
901
  	/* these get messy on amd64 due to alignment differences */
2af563d07   Arnd Bergmann   compat_ioctl: mov...
902
903
904
  	case FS_IOC_RESVSP_32:
  	case FS_IOC_RESVSP64_32:
  		error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
77b904019   Arnd Bergmann   compat_ioctl: sim...
905
  		break;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
906
907
908
909
  	case FS_IOC_UNRESVSP_32:
  	case FS_IOC_UNRESVSP64_32:
  		error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
  				compat_ptr(arg));
77b904019   Arnd Bergmann   compat_ioctl: sim...
910
  		break;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
911
912
913
  	case FS_IOC_ZERO_RANGE_32:
  		error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
  				compat_ptr(arg));
77b904019   Arnd Bergmann   compat_ioctl: sim...
914
  		break;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
915
  #endif
77b904019   Arnd Bergmann   compat_ioctl: sim...
916
  	/*
4c5b47997   Miklos Szeredi   vfs: add fileattr...
917
918
919
920
921
922
923
924
925
  	 * These access 32-bit values anyway so no further handling is
  	 * necessary.
  	 */
  	case FS_IOC32_GETFLAGS:
  	case FS_IOC32_SETFLAGS:
  		cmd = (cmd == FS_IOC32_GETFLAGS) ?
  			FS_IOC_GETFLAGS : FS_IOC_SETFLAGS;
  		fallthrough;
  	/*
77b904019   Arnd Bergmann   compat_ioctl: sim...
926
927
928
929
  	 * everything else in do_vfs_ioctl() takes either a compatible
  	 * pointer argument or no argument -- call it with a modified
  	 * argument.
  	 */
2af563d07   Arnd Bergmann   compat_ioctl: mov...
930
  	default:
77b904019   Arnd Bergmann   compat_ioctl: sim...
931
932
933
934
935
936
  		error = do_vfs_ioctl(f.file, fd, cmd,
  				     (unsigned long)compat_ptr(arg));
  		if (error != -ENOIOCTLCMD)
  			break;
  
  		if (f.file->f_op->compat_ioctl)
2af563d07   Arnd Bergmann   compat_ioctl: mov...
937
  			error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
77b904019   Arnd Bergmann   compat_ioctl: sim...
938
939
940
  		if (error == -ENOIOCTLCMD)
  			error = -ENOTTY;
  		break;
2af563d07   Arnd Bergmann   compat_ioctl: mov...
941
  	}
2af563d07   Arnd Bergmann   compat_ioctl: mov...
942
   out:
77b904019   Arnd Bergmann   compat_ioctl: sim...
943
  	fdput(f);
2af563d07   Arnd Bergmann   compat_ioctl: mov...
944
945
  	return error;
  }
2952db0fd   Arnd Bergmann   compat_ioctl: add...
946
  #endif