]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - fs/compat.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
[karo-tx-linux.git] / fs / compat.c
index c61b506f5bc94ba0dcac0d9a28a7ab1070ac3a66..190b38b39d9ed74efa5816e437232f86ee7070d4 100644 (file)
  *  published by the Free Software Foundation.
  */
 
-#include <linux/stddef.h>
-#include <linux/kernel.h>
-#include <linux/linkage.h>
 #include <linux/compat.h>
-#include <linux/errno.h>
-#include <linux/time.h>
-#include <linux/cred.h>
-#include <linux/fs.h>
-#include <linux/fcntl.h>
-#include <linux/namei.h>
-#include <linux/file.h>
-#include <linux/fdtable.h>
-#include <linux/vfs.h>
-#include <linux/ioctl.h>
-#include <linux/init.h>
 #include <linux/ncp_mount.h>
 #include <linux/nfs4_mount.h>
 #include <linux/syscalls.h>
-#include <linux/ctype.h>
-#include <linux/dirent.h>
-#include <linux/fsnotify.h>
-#include <linux/highuid.h>
-#include <linux/personality.h>
-#include <linux/rwsem.h>
-#include <linux/tsacct_kern.h>
-#include <linux/security.h>
-#include <linux/highmem.h>
-#include <linux/signal.h>
-#include <linux/poll.h>
-#include <linux/mm.h>
-#include <linux/fs_struct.h>
 #include <linux/slab.h>
-#include <linux/pagemap.h>
-#include <linux/aio.h>
-
 #include <linux/uaccess.h>
-#include <asm/mmu_context.h>
-#include <asm/ioctls.h>
 #include "internal.h"
 
-/*
- * Not all architectures have sys_utime, so implement this in terms
- * of sys_utimes.
- */
-COMPAT_SYSCALL_DEFINE2(utime, const char __user *, filename,
-                      struct compat_utimbuf __user *, t)
-{
-       struct timespec tv[2];
-
-       if (t) {
-               if (get_user(tv[0].tv_sec, &t->actime) ||
-                   get_user(tv[1].tv_sec, &t->modtime))
-                       return -EFAULT;
-               tv[0].tv_nsec = 0;
-               tv[1].tv_nsec = 0;
-       }
-       return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
-}
-
-COMPAT_SYSCALL_DEFINE4(utimensat, unsigned int, dfd, const char __user *, filename, struct compat_timespec __user *, t, int, flags)
-{
-       struct timespec tv[2];
-
-       if  (t) {
-               if (compat_get_timespec(&tv[0], &t[0]) ||
-                   compat_get_timespec(&tv[1], &t[1]))
-                       return -EFAULT;
-
-               if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
-                       return 0;
-       }
-       return do_utimes(dfd, filename, t ? tv : NULL, flags);
-}
-
-COMPAT_SYSCALL_DEFINE3(futimesat, unsigned int, dfd, const char __user *, filename, struct compat_timeval __user *, t)
-{
-       struct timespec tv[2];
-
-       if (t) {
-               if (get_user(tv[0].tv_sec, &t[0].tv_sec) ||
-                   get_user(tv[0].tv_nsec, &t[0].tv_usec) ||
-                   get_user(tv[1].tv_sec, &t[1].tv_sec) ||
-                   get_user(tv[1].tv_nsec, &t[1].tv_usec))
-                       return -EFAULT;
-               if (tv[0].tv_nsec >= 1000000 || tv[0].tv_nsec < 0 ||
-                   tv[1].tv_nsec >= 1000000 || tv[1].tv_nsec < 0)
-                       return -EINVAL;
-               tv[0].tv_nsec *= 1000;
-               tv[1].tv_nsec *= 1000;
-       }
-       return do_utimes(dfd, filename, t ? tv : NULL, 0);
-}
-
-COMPAT_SYSCALL_DEFINE2(utimes, const char __user *, filename, struct compat_timeval __user *, t)
-{
-       return compat_sys_futimesat(AT_FDCWD, filename, t);
-}
-
-static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
-{
-       struct compat_stat tmp;
-
-       if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
-               return -EOVERFLOW;
-
-       memset(&tmp, 0, sizeof(tmp));
-       tmp.st_dev = old_encode_dev(stat->dev);
-       tmp.st_ino = stat->ino;
-       if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
-               return -EOVERFLOW;
-       tmp.st_mode = stat->mode;
-       tmp.st_nlink = stat->nlink;
-       if (tmp.st_nlink != stat->nlink)
-               return -EOVERFLOW;
-       SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
-       SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
-       tmp.st_rdev = old_encode_dev(stat->rdev);
-       if ((u64) stat->size > MAX_NON_LFS)
-               return -EOVERFLOW;
-       tmp.st_size = stat->size;
-       tmp.st_atime = stat->atime.tv_sec;
-       tmp.st_atime_nsec = stat->atime.tv_nsec;
-       tmp.st_mtime = stat->mtime.tv_sec;
-       tmp.st_mtime_nsec = stat->mtime.tv_nsec;
-       tmp.st_ctime = stat->ctime.tv_sec;
-       tmp.st_ctime_nsec = stat->ctime.tv_nsec;
-       tmp.st_blocks = stat->blocks;
-       tmp.st_blksize = stat->blksize;
-       return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
-}
-
-COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename,
-                      struct compat_stat __user *, statbuf)
-{
-       struct kstat stat;
-       int error;
-
-       error = vfs_stat(filename, &stat);
-       if (error)
-               return error;
-       return cp_compat_stat(&stat, statbuf);
-}
-
-COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename,
-                      struct compat_stat __user *, statbuf)
-{
-       struct kstat stat;
-       int error;
-
-       error = vfs_lstat(filename, &stat);
-       if (error)
-               return error;
-       return cp_compat_stat(&stat, statbuf);
-}
-
-#ifndef __ARCH_WANT_STAT64
-COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd,
-                      const char __user *, filename,
-                      struct compat_stat __user *, statbuf, int, flag)
-{
-       struct kstat stat;
-       int error;
-
-       error = vfs_fstatat(dfd, filename, &stat, flag);
-       if (error)
-               return error;
-       return cp_compat_stat(&stat, statbuf);
-}
-#endif
-
-COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd,
-                      struct compat_stat __user *, statbuf)
-{
-       struct kstat stat;
-       int error = vfs_fstat(fd, &stat);
-
-       if (!error)
-               error = cp_compat_stat(&stat, statbuf);
-       return error;
-}
-
-static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
-{
-       
-       if (sizeof ubuf->f_blocks == 4) {
-               if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
-                    kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)
-                       return -EOVERFLOW;
-               /* f_files and f_ffree may be -1; it's okay
-                * to stuff that into 32 bits */
-               if (kbuf->f_files != 0xffffffffffffffffULL
-                && (kbuf->f_files & 0xffffffff00000000ULL))
-                       return -EOVERFLOW;
-               if (kbuf->f_ffree != 0xffffffffffffffffULL
-                && (kbuf->f_ffree & 0xffffffff00000000ULL))
-                       return -EOVERFLOW;
-       }
-       if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
-           __put_user(kbuf->f_type, &ubuf->f_type) ||
-           __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
-           __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
-           __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
-           __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
-           __put_user(kbuf->f_files, &ubuf->f_files) ||
-           __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
-           __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
-           __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
-           __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
-           __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
-           __put_user(kbuf->f_flags, &ubuf->f_flags) ||
-           __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
-               return -EFAULT;
-       return 0;
-}
-
-/*
- * The following statfs calls are copies of code from fs/statfs.c and
- * should be checked against those from time to time
- */
-COMPAT_SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct compat_statfs __user *, buf)
-{
-       struct kstatfs tmp;
-       int error = user_statfs(pathname, &tmp);
-       if (!error)
-               error = put_compat_statfs(buf, &tmp);
-       return error;
-}
-
-COMPAT_SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct compat_statfs __user *, buf)
-{
-       struct kstatfs tmp;
-       int error = fd_statfs(fd, &tmp);
-       if (!error)
-               error = put_compat_statfs(buf, &tmp);
-       return error;
-}
-
-static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
-{
-       if (sizeof(ubuf->f_bsize) == 4) {
-               if ((kbuf->f_type | kbuf->f_bsize | kbuf->f_namelen |
-                    kbuf->f_frsize | kbuf->f_flags) & 0xffffffff00000000ULL)
-                       return -EOVERFLOW;
-               /* f_files and f_ffree may be -1; it's okay
-                * to stuff that into 32 bits */
-               if (kbuf->f_files != 0xffffffffffffffffULL
-                && (kbuf->f_files & 0xffffffff00000000ULL))
-                       return -EOVERFLOW;
-               if (kbuf->f_ffree != 0xffffffffffffffffULL
-                && (kbuf->f_ffree & 0xffffffff00000000ULL))
-                       return -EOVERFLOW;
-       }
-       if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
-           __put_user(kbuf->f_type, &ubuf->f_type) ||
-           __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
-           __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
-           __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
-           __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
-           __put_user(kbuf->f_files, &ubuf->f_files) ||
-           __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
-           __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
-           __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
-           __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
-           __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
-           __put_user(kbuf->f_flags, &ubuf->f_flags) ||
-           __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))
-               return -EFAULT;
-       return 0;
-}
-
-COMPAT_SYSCALL_DEFINE3(statfs64, const char __user *, pathname, compat_size_t, sz, struct compat_statfs64 __user *, buf)
-{
-       struct kstatfs tmp;
-       int error;
-
-       if (sz != sizeof(*buf))
-               return -EINVAL;
-
-       error = user_statfs(pathname, &tmp);
-       if (!error)
-               error = put_compat_statfs64(buf, &tmp);
-       return error;
-}
-
-COMPAT_SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, compat_size_t, sz, struct compat_statfs64 __user *, buf)
-{
-       struct kstatfs tmp;
-       int error;
-
-       if (sz != sizeof(*buf))
-               return -EINVAL;
-
-       error = fd_statfs(fd, &tmp);
-       if (!error)
-               error = put_compat_statfs64(buf, &tmp);
-       return error;
-}
-
-/*
- * This is a copy of sys_ustat, just dealing with a structure layout.
- * Given how simple this syscall is that apporach is more maintainable
- * than the various conversion hacks.
- */
-COMPAT_SYSCALL_DEFINE2(ustat, unsigned, dev, struct compat_ustat __user *, u)
-{
-       struct compat_ustat tmp;
-       struct kstatfs sbuf;
-       int err = vfs_ustat(new_decode_dev(dev), &sbuf);
-       if (err)
-               return err;
-
-       memset(&tmp, 0, sizeof(struct compat_ustat));
-       tmp.f_tfree = sbuf.f_bfree;
-       tmp.f_tinode = sbuf.f_ffree;
-       if (copy_to_user(u, &tmp, sizeof(struct compat_ustat)))
-               return -EFAULT;
-       return 0;
-}
-
-static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
-{
-       if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
-           __get_user(kfl->l_type, &ufl->l_type) ||
-           __get_user(kfl->l_whence, &ufl->l_whence) ||
-           __get_user(kfl->l_start, &ufl->l_start) ||
-           __get_user(kfl->l_len, &ufl->l_len) ||
-           __get_user(kfl->l_pid, &ufl->l_pid))
-               return -EFAULT;
-       return 0;
-}
-
-static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
-{
-       if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
-           __put_user(kfl->l_type, &ufl->l_type) ||
-           __put_user(kfl->l_whence, &ufl->l_whence) ||
-           __put_user(kfl->l_start, &ufl->l_start) ||
-           __put_user(kfl->l_len, &ufl->l_len) ||
-           __put_user(kfl->l_pid, &ufl->l_pid))
-               return -EFAULT;
-       return 0;
-}
-
-#ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
-static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
-{
-       if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
-           __get_user(kfl->l_type, &ufl->l_type) ||
-           __get_user(kfl->l_whence, &ufl->l_whence) ||
-           __get_user(kfl->l_start, &ufl->l_start) ||
-           __get_user(kfl->l_len, &ufl->l_len) ||
-           __get_user(kfl->l_pid, &ufl->l_pid))
-               return -EFAULT;
-       return 0;
-}
-#endif
-
-#ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
-static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
-{
-       if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
-           __put_user(kfl->l_type, &ufl->l_type) ||
-           __put_user(kfl->l_whence, &ufl->l_whence) ||
-           __put_user(kfl->l_start, &ufl->l_start) ||
-           __put_user(kfl->l_len, &ufl->l_len) ||
-           __put_user(kfl->l_pid, &ufl->l_pid))
-               return -EFAULT;
-       return 0;
-}
-#endif
-
-static unsigned int
-convert_fcntl_cmd(unsigned int cmd)
-{
-       switch (cmd) {
-       case F_GETLK64:
-               return F_GETLK;
-       case F_SETLK64:
-               return F_SETLK;
-       case F_SETLKW64:
-               return F_SETLKW;
-       }
-
-       return cmd;
-}
-
-COMPAT_SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
-                      compat_ulong_t, arg)
-{
-       mm_segment_t old_fs;
-       struct flock f;
-       long ret;
-       unsigned int conv_cmd;
-
-       switch (cmd) {
-       case F_GETLK:
-       case F_SETLK:
-       case F_SETLKW:
-               ret = get_compat_flock(&f, compat_ptr(arg));
-               if (ret != 0)
-                       break;
-               old_fs = get_fs();
-               set_fs(KERNEL_DS);
-               ret = sys_fcntl(fd, cmd, (unsigned long)&f);
-               set_fs(old_fs);
-               if (cmd == F_GETLK && ret == 0) {
-                       /* GETLK was successful and we need to return the data...
-                        * but it needs to fit in the compat structure.
-                        * l_start shouldn't be too big, unless the original
-                        * start + end is greater than COMPAT_OFF_T_MAX, in which
-                        * case the app was asking for trouble, so we return
-                        * -EOVERFLOW in that case.
-                        * l_len could be too big, in which case we just truncate it,
-                        * and only allow the app to see that part of the conflicting
-                        * lock that might make sense to it anyway
-                        */
-
-                       if (f.l_start > COMPAT_OFF_T_MAX)
-                               ret = -EOVERFLOW;
-                       if (f.l_len > COMPAT_OFF_T_MAX)
-                               f.l_len = COMPAT_OFF_T_MAX;
-                       if (ret == 0)
-                               ret = put_compat_flock(&f, compat_ptr(arg));
-               }
-               break;
-
-       case F_GETLK64:
-       case F_SETLK64:
-       case F_SETLKW64:
-       case F_OFD_GETLK:
-       case F_OFD_SETLK:
-       case F_OFD_SETLKW:
-               ret = get_compat_flock64(&f, compat_ptr(arg));
-               if (ret != 0)
-                       break;
-               old_fs = get_fs();
-               set_fs(KERNEL_DS);
-               conv_cmd = convert_fcntl_cmd(cmd);
-               ret = sys_fcntl(fd, conv_cmd, (unsigned long)&f);
-               set_fs(old_fs);
-               if ((conv_cmd == F_GETLK || conv_cmd == F_OFD_GETLK) && ret == 0) {
-                       /* need to return lock information - see above for commentary */
-                       if (f.l_start > COMPAT_LOFF_T_MAX)
-                               ret = -EOVERFLOW;
-                       if (f.l_len > COMPAT_LOFF_T_MAX)
-                               f.l_len = COMPAT_LOFF_T_MAX;
-                       if (ret == 0)
-                               ret = put_compat_flock64(&f, compat_ptr(arg));
-               }
-               break;
-
-       default:
-               ret = sys_fcntl(fd, cmd, arg);
-               break;
-       }
-       return ret;
-}
-
-COMPAT_SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd,
-                      compat_ulong_t, arg)
-{
-       switch (cmd) {
-       case F_GETLK64:
-       case F_SETLK64:
-       case F_SETLKW64:
-       case F_OFD_GETLK:
-       case F_OFD_SETLK:
-       case F_OFD_SETLKW:
-               return -EINVAL;
-       }
-       return compat_sys_fcntl64(fd, cmd, arg);
-}
-
-/* A write operation does a read from user space and vice versa */
-#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
-
-ssize_t compat_rw_copy_check_uvector(int type,
-               const struct compat_iovec __user *uvector, unsigned long nr_segs,
-               unsigned long fast_segs, struct iovec *fast_pointer,
-               struct iovec **ret_pointer)
-{
-       compat_ssize_t tot_len;
-       struct iovec *iov = *ret_pointer = fast_pointer;
-       ssize_t ret = 0;
-       int seg;
-
-       /*
-        * SuS says "The readv() function *may* fail if the iovcnt argument
-        * was less than or equal to 0, or greater than {IOV_MAX}.  Linux has
-        * traditionally returned zero for zero segments, so...
-        */
-       if (nr_segs == 0)
-               goto out;
-
-       ret = -EINVAL;
-       if (nr_segs > UIO_MAXIOV)
-               goto out;
-       if (nr_segs > fast_segs) {
-               ret = -ENOMEM;
-               iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);
-               if (iov == NULL)
-                       goto out;
-       }
-       *ret_pointer = iov;
-
-       ret = -EFAULT;
-       if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
-               goto out;
-
-       /*
-        * Single unix specification:
-        * We should -EINVAL if an element length is not >= 0 and fitting an
-        * ssize_t.
-        *
-        * In Linux, the total length is limited to MAX_RW_COUNT, there is
-        * no overflow possibility.
-        */
-       tot_len = 0;
-       ret = -EINVAL;
-       for (seg = 0; seg < nr_segs; seg++) {
-               compat_uptr_t buf;
-               compat_ssize_t len;
-
-               if (__get_user(len, &uvector->iov_len) ||
-                  __get_user(buf, &uvector->iov_base)) {
-                       ret = -EFAULT;
-                       goto out;
-               }
-               if (len < 0)    /* size_t not fitting in compat_ssize_t .. */
-                       goto out;
-               if (type >= 0 &&
-                   !access_ok(vrfy_dir(type), compat_ptr(buf), len)) {
-                       ret = -EFAULT;
-                       goto out;
-               }
-               if (len > MAX_RW_COUNT - tot_len)
-                       len = MAX_RW_COUNT - tot_len;
-               tot_len += len;
-               iov->iov_base = compat_ptr(buf);
-               iov->iov_len = (compat_size_t) len;
-               uvector++;
-               iov++;
-       }
-       ret = tot_len;
-
-out:
-       return ret;
-}
-
 struct compat_ncp_mount_data {
        compat_int_t version;
        compat_uint_t ncp_fd;
@@ -744,653 +203,3 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name,
  out:
        return retval;
 }
-
-struct compat_old_linux_dirent {
-       compat_ulong_t  d_ino;
-       compat_ulong_t  d_offset;
-       unsigned short  d_namlen;
-       char            d_name[1];
-};
-
-struct compat_readdir_callback {
-       struct dir_context ctx;
-       struct compat_old_linux_dirent __user *dirent;
-       int result;
-};
-
-static int compat_fillonedir(struct dir_context *ctx, const char *name,
-                            int namlen, loff_t offset, u64 ino,
-                            unsigned int d_type)
-{
-       struct compat_readdir_callback *buf =
-               container_of(ctx, struct compat_readdir_callback, ctx);
-       struct compat_old_linux_dirent __user *dirent;
-       compat_ulong_t d_ino;
-
-       if (buf->result)
-               return -EINVAL;
-       d_ino = ino;
-       if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
-               buf->result = -EOVERFLOW;
-               return -EOVERFLOW;
-       }
-       buf->result++;
-       dirent = buf->dirent;
-       if (!access_ok(VERIFY_WRITE, dirent,
-                       (unsigned long)(dirent->d_name + namlen + 1) -
-                               (unsigned long)dirent))
-               goto efault;
-       if (    __put_user(d_ino, &dirent->d_ino) ||
-               __put_user(offset, &dirent->d_offset) ||
-               __put_user(namlen, &dirent->d_namlen) ||
-               __copy_to_user(dirent->d_name, name, namlen) ||
-               __put_user(0, dirent->d_name + namlen))
-               goto efault;
-       return 0;
-efault:
-       buf->result = -EFAULT;
-       return -EFAULT;
-}
-
-COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
-               struct compat_old_linux_dirent __user *, dirent, unsigned int, count)
-{
-       int error;
-       struct fd f = fdget_pos(fd);
-       struct compat_readdir_callback buf = {
-               .ctx.actor = compat_fillonedir,
-               .dirent = dirent
-       };
-
-       if (!f.file)
-               return -EBADF;
-
-       error = iterate_dir(f.file, &buf.ctx);
-       if (buf.result)
-               error = buf.result;
-
-       fdput_pos(f);
-       return error;
-}
-
-struct compat_linux_dirent {
-       compat_ulong_t  d_ino;
-       compat_ulong_t  d_off;
-       unsigned short  d_reclen;
-       char            d_name[1];
-};
-
-struct compat_getdents_callback {
-       struct dir_context ctx;
-       struct compat_linux_dirent __user *current_dir;
-       struct compat_linux_dirent __user *previous;
-       int count;
-       int error;
-};
-
-static int compat_filldir(struct dir_context *ctx, const char *name, int namlen,
-               loff_t offset, u64 ino, unsigned int d_type)
-{
-       struct compat_linux_dirent __user * dirent;
-       struct compat_getdents_callback *buf =
-               container_of(ctx, struct compat_getdents_callback, ctx);
-       compat_ulong_t d_ino;
-       int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +
-               namlen + 2, sizeof(compat_long_t));
-
-       buf->error = -EINVAL;   /* only used if we fail.. */
-       if (reclen > buf->count)
-               return -EINVAL;
-       d_ino = ino;
-       if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
-               buf->error = -EOVERFLOW;
-               return -EOVERFLOW;
-       }
-       dirent = buf->previous;
-       if (dirent) {
-               if (signal_pending(current))
-                       return -EINTR;
-               if (__put_user(offset, &dirent->d_off))
-                       goto efault;
-       }
-       dirent = buf->current_dir;
-       if (__put_user(d_ino, &dirent->d_ino))
-               goto efault;
-       if (__put_user(reclen, &dirent->d_reclen))
-               goto efault;
-       if (copy_to_user(dirent->d_name, name, namlen))
-               goto efault;
-       if (__put_user(0, dirent->d_name + namlen))
-               goto efault;
-       if (__put_user(d_type, (char  __user *) dirent + reclen - 1))
-               goto efault;
-       buf->previous = dirent;
-       dirent = (void __user *)dirent + reclen;
-       buf->current_dir = dirent;
-       buf->count -= reclen;
-       return 0;
-efault:
-       buf->error = -EFAULT;
-       return -EFAULT;
-}
-
-COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd,
-               struct compat_linux_dirent __user *, dirent, unsigned int, count)
-{
-       struct fd f;
-       struct compat_linux_dirent __user * lastdirent;
-       struct compat_getdents_callback buf = {
-               .ctx.actor = compat_filldir,
-               .current_dir = dirent,
-               .count = count
-       };
-       int error;
-
-       if (!access_ok(VERIFY_WRITE, dirent, count))
-               return -EFAULT;
-
-       f = fdget_pos(fd);
-       if (!f.file)
-               return -EBADF;
-
-       error = iterate_dir(f.file, &buf.ctx);
-       if (error >= 0)
-               error = buf.error;
-       lastdirent = buf.previous;
-       if (lastdirent) {
-               if (put_user(buf.ctx.pos, &lastdirent->d_off))
-                       error = -EFAULT;
-               else
-                       error = count - buf.count;
-       }
-       fdput_pos(f);
-       return error;
-}
-
-#ifdef __ARCH_WANT_COMPAT_SYS_GETDENTS64
-
-struct compat_getdents_callback64 {
-       struct dir_context ctx;
-       struct linux_dirent64 __user *current_dir;
-       struct linux_dirent64 __user *previous;
-       int count;
-       int error;
-};
-
-static int compat_filldir64(struct dir_context *ctx, const char *name,
-                           int namlen, loff_t offset, u64 ino,
-                           unsigned int d_type)
-{
-       struct linux_dirent64 __user *dirent;
-       struct compat_getdents_callback64 *buf =
-               container_of(ctx, struct compat_getdents_callback64, ctx);
-       int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
-               sizeof(u64));
-       u64 off;
-
-       buf->error = -EINVAL;   /* only used if we fail.. */
-       if (reclen > buf->count)
-               return -EINVAL;
-       dirent = buf->previous;
-
-       if (dirent) {
-               if (signal_pending(current))
-                       return -EINTR;
-               if (__put_user_unaligned(offset, &dirent->d_off))
-                       goto efault;
-       }
-       dirent = buf->current_dir;
-       if (__put_user_unaligned(ino, &dirent->d_ino))
-               goto efault;
-       off = 0;
-       if (__put_user_unaligned(off, &dirent->d_off))
-               goto efault;
-       if (__put_user(reclen, &dirent->d_reclen))
-               goto efault;
-       if (__put_user(d_type, &dirent->d_type))
-               goto efault;
-       if (copy_to_user(dirent->d_name, name, namlen))
-               goto efault;
-       if (__put_user(0, dirent->d_name + namlen))
-               goto efault;
-       buf->previous = dirent;
-       dirent = (void __user *)dirent + reclen;
-       buf->current_dir = dirent;
-       buf->count -= reclen;
-       return 0;
-efault:
-       buf->error = -EFAULT;
-       return -EFAULT;
-}
-
-COMPAT_SYSCALL_DEFINE3(getdents64, unsigned int, fd,
-               struct linux_dirent64 __user *, dirent, unsigned int, count)
-{
-       struct fd f;
-       struct linux_dirent64 __user * lastdirent;
-       struct compat_getdents_callback64 buf = {
-               .ctx.actor = compat_filldir64,
-               .current_dir = dirent,
-               .count = count
-       };
-       int error;
-
-       if (!access_ok(VERIFY_WRITE, dirent, count))
-               return -EFAULT;
-
-       f = fdget_pos(fd);
-       if (!f.file)
-               return -EBADF;
-
-       error = iterate_dir(f.file, &buf.ctx);
-       if (error >= 0)
-               error = buf.error;
-       lastdirent = buf.previous;
-       if (lastdirent) {
-               typeof(lastdirent->d_off) d_off = buf.ctx.pos;
-               if (__put_user_unaligned(d_off, &lastdirent->d_off))
-                       error = -EFAULT;
-               else
-                       error = count - buf.count;
-       }
-       fdput_pos(f);
-       return error;
-}
-#endif /* __ARCH_WANT_COMPAT_SYS_GETDENTS64 */
-
-/*
- * Exactly like fs/open.c:sys_open(), except that it doesn't set the
- * O_LARGEFILE flag.
- */
-COMPAT_SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode)
-{
-       return do_sys_open(AT_FDCWD, filename, flags, mode);
-}
-
-/*
- * Exactly like fs/open.c:sys_openat(), except that it doesn't set the
- * O_LARGEFILE flag.
- */
-COMPAT_SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags, umode_t, mode)
-{
-       return do_sys_open(dfd, filename, flags, mode);
-}
-
-#define __COMPAT_NFDBITS       (8 * sizeof(compat_ulong_t))
-
-static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
-                                     int timeval, int ret)
-{
-       struct timespec ts;
-
-       if (!p)
-               return ret;
-
-       if (current->personality & STICKY_TIMEOUTS)
-               goto sticky;
-
-       /* No update for zero timeout */
-       if (!end_time->tv_sec && !end_time->tv_nsec)
-               return ret;
-
-       ktime_get_ts(&ts);
-       ts = timespec_sub(*end_time, ts);
-       if (ts.tv_sec < 0)
-               ts.tv_sec = ts.tv_nsec = 0;
-
-       if (timeval) {
-               struct compat_timeval rtv;
-
-               rtv.tv_sec = ts.tv_sec;
-               rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
-
-               if (!copy_to_user(p, &rtv, sizeof(rtv)))
-                       return ret;
-       } else {
-               struct compat_timespec rts;
-
-               rts.tv_sec = ts.tv_sec;
-               rts.tv_nsec = ts.tv_nsec;
-
-               if (!copy_to_user(p, &rts, sizeof(rts)))
-                       return ret;
-       }
-       /*
-        * If an application puts its timeval in read-only memory, we
-        * don't want the Linux-specific update to the timeval to
-        * cause a fault after the select has completed
-        * successfully. However, because we're not updating the
-        * timeval, we can't restart the system call.
-        */
-
-sticky:
-       if (ret == -ERESTARTNOHAND)
-               ret = -EINTR;
-       return ret;
-}
-
-/*
- * Ooo, nasty.  We need here to frob 32-bit unsigned longs to
- * 64-bit unsigned longs.
- */
-static
-int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
-                       unsigned long *fdset)
-{
-       nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
-       if (ufdset) {
-               unsigned long odd;
-
-               if (!access_ok(VERIFY_WRITE, ufdset, nr*sizeof(compat_ulong_t)))
-                       return -EFAULT;
-
-               odd = nr & 1UL;
-               nr &= ~1UL;
-               while (nr) {
-                       unsigned long h, l;
-                       if (__get_user(l, ufdset) || __get_user(h, ufdset+1))
-                               return -EFAULT;
-                       ufdset += 2;
-                       *fdset++ = h << 32 | l;
-                       nr -= 2;
-               }
-               if (odd && __get_user(*fdset, ufdset))
-                       return -EFAULT;
-       } else {
-               /* Tricky, must clear full unsigned long in the
-                * kernel fdset at the end, this makes sure that
-                * actually happens.
-                */
-               memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
-       }
-       return 0;
-}
-
-static
-int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
-                     unsigned long *fdset)
-{
-       unsigned long odd;
-       nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);
-
-       if (!ufdset)
-               return 0;
-
-       odd = nr & 1UL;
-       nr &= ~1UL;
-       while (nr) {
-               unsigned long h, l;
-               l = *fdset++;
-               h = l >> 32;
-               if (__put_user(l, ufdset) || __put_user(h, ufdset+1))
-                       return -EFAULT;
-               ufdset += 2;
-               nr -= 2;
-       }
-       if (odd && __put_user(*fdset, ufdset))
-               return -EFAULT;
-       return 0;
-}
-
-
-/*
- * This is a virtual copy of sys_select from fs/select.c and probably
- * should be compared to it from time to time
- */
-
-/*
- * We can actually return ERESTARTSYS instead of EINTR, but I'd
- * like to be certain this leads to no problems. So I return
- * EINTR just for safety.
- *
- * Update: ERESTARTSYS breaks at least the xview clock binary, so
- * I'm trying ERESTARTNOHAND which restart only when you want to.
- */
-int compat_core_sys_select(int n, compat_ulong_t __user *inp,
-       compat_ulong_t __user *outp, compat_ulong_t __user *exp,
-       struct timespec *end_time)
-{
-       fd_set_bits fds;
-       void *bits;
-       int size, max_fds, ret = -EINVAL;
-       struct fdtable *fdt;
-       long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
-
-       if (n < 0)
-               goto out_nofds;
-
-       /* max_fds can increase, so grab it once to avoid race */
-       rcu_read_lock();
-       fdt = files_fdtable(current->files);
-       max_fds = fdt->max_fds;
-       rcu_read_unlock();
-       if (n > max_fds)
-               n = max_fds;
-
-       /*
-        * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
-        * since we used fdset we need to allocate memory in units of
-        * long-words.
-        */
-       size = FDS_BYTES(n);
-       bits = stack_fds;
-       if (size > sizeof(stack_fds) / 6) {
-               bits = kmalloc(6 * size, GFP_KERNEL);
-               ret = -ENOMEM;
-               if (!bits)
-                       goto out_nofds;
-       }
-       fds.in      = (unsigned long *)  bits;
-       fds.out     = (unsigned long *) (bits +   size);
-       fds.ex      = (unsigned long *) (bits + 2*size);
-       fds.res_in  = (unsigned long *) (bits + 3*size);
-       fds.res_out = (unsigned long *) (bits + 4*size);
-       fds.res_ex  = (unsigned long *) (bits + 5*size);
-
-       if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
-           (ret = compat_get_fd_set(n, outp, fds.out)) ||
-           (ret = compat_get_fd_set(n, exp, fds.ex)))
-               goto out;
-       zero_fd_set(n, fds.res_in);
-       zero_fd_set(n, fds.res_out);
-       zero_fd_set(n, fds.res_ex);
-
-       ret = do_select(n, &fds, end_time);
-
-       if (ret < 0)
-               goto out;
-       if (!ret) {
-               ret = -ERESTARTNOHAND;
-               if (signal_pending(current))
-                       goto out;
-               ret = 0;
-       }
-
-       if (compat_set_fd_set(n, inp, fds.res_in) ||
-           compat_set_fd_set(n, outp, fds.res_out) ||
-           compat_set_fd_set(n, exp, fds.res_ex))
-               ret = -EFAULT;
-out:
-       if (bits != stack_fds)
-               kfree(bits);
-out_nofds:
-       return ret;
-}
-
-COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp,
-       compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
-       struct compat_timeval __user *, tvp)
-{
-       struct timespec end_time, *to = NULL;
-       struct compat_timeval tv;
-       int ret;
-
-       if (tvp) {
-               if (copy_from_user(&tv, tvp, sizeof(tv)))
-                       return -EFAULT;
-
-               to = &end_time;
-               if (poll_select_set_timeout(to,
-                               tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
-                               (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
-                       return -EINVAL;
-       }
-
-       ret = compat_core_sys_select(n, inp, outp, exp, to);
-       ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
-
-       return ret;
-}
-
-struct compat_sel_arg_struct {
-       compat_ulong_t n;
-       compat_uptr_t inp;
-       compat_uptr_t outp;
-       compat_uptr_t exp;
-       compat_uptr_t tvp;
-};
-
-COMPAT_SYSCALL_DEFINE1(old_select, struct compat_sel_arg_struct __user *, arg)
-{
-       struct compat_sel_arg_struct a;
-
-       if (copy_from_user(&a, arg, sizeof(a)))
-               return -EFAULT;
-       return compat_sys_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp),
-                                compat_ptr(a.exp), compat_ptr(a.tvp));
-}
-
-static long do_compat_pselect(int n, compat_ulong_t __user *inp,
-       compat_ulong_t __user *outp, compat_ulong_t __user *exp,
-       struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
-       compat_size_t sigsetsize)
-{
-       compat_sigset_t ss32;
-       sigset_t ksigmask, sigsaved;
-       struct compat_timespec ts;
-       struct timespec end_time, *to = NULL;
-       int ret;
-
-       if (tsp) {
-               if (copy_from_user(&ts, tsp, sizeof(ts)))
-                       return -EFAULT;
-
-               to = &end_time;
-               if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
-                       return -EINVAL;
-       }
-
-       if (sigmask) {
-               if (sigsetsize != sizeof(compat_sigset_t))
-                       return -EINVAL;
-               if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
-                       return -EFAULT;
-               sigset_from_compat(&ksigmask, &ss32);
-
-               sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
-               sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
-       }
-
-       ret = compat_core_sys_select(n, inp, outp, exp, to);
-       ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
-
-       if (ret == -ERESTARTNOHAND) {
-               /*
-                * Don't restore the signal mask yet. Let do_signal() deliver
-                * the signal on the way back to userspace, before the signal
-                * mask is restored.
-                */
-               if (sigmask) {
-                       memcpy(&current->saved_sigmask, &sigsaved,
-                                       sizeof(sigsaved));
-                       set_restore_sigmask();
-               }
-       } else if (sigmask)
-               sigprocmask(SIG_SETMASK, &sigsaved, NULL);
-
-       return ret;
-}
-
-COMPAT_SYSCALL_DEFINE6(pselect6, int, n, compat_ulong_t __user *, inp,
-       compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
-       struct compat_timespec __user *, tsp, void __user *, sig)
-{
-       compat_size_t sigsetsize = 0;
-       compat_uptr_t up = 0;
-
-       if (sig) {
-               if (!access_ok(VERIFY_READ, sig,
-                               sizeof(compat_uptr_t)+sizeof(compat_size_t)) ||
-                       __get_user(up, (compat_uptr_t __user *)sig) ||
-                       __get_user(sigsetsize,
-                               (compat_size_t __user *)(sig+sizeof(up))))
-                       return -EFAULT;
-       }
-       return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(up),
-                                sigsetsize);
-}
-
-COMPAT_SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds,
-       unsigned int,  nfds, struct compat_timespec __user *, tsp,
-       const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
-{
-       compat_sigset_t ss32;
-       sigset_t ksigmask, sigsaved;
-       struct compat_timespec ts;
-       struct timespec end_time, *to = NULL;
-       int ret;
-
-       if (tsp) {
-               if (copy_from_user(&ts, tsp, sizeof(ts)))
-                       return -EFAULT;
-
-               to = &end_time;
-               if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
-                       return -EINVAL;
-       }
-
-       if (sigmask) {
-               if (sigsetsize != sizeof(compat_sigset_t))
-                       return -EINVAL;
-               if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
-                       return -EFAULT;
-               sigset_from_compat(&ksigmask, &ss32);
-
-               sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
-               sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
-       }
-
-       ret = do_sys_poll(ufds, nfds, to);
-
-       /* We can restart this syscall, usually */
-       if (ret == -EINTR) {
-               /*
-                * Don't restore the signal mask yet. Let do_signal() deliver
-                * the signal on the way back to userspace, before the signal
-                * mask is restored.
-                */
-               if (sigmask) {
-                       memcpy(&current->saved_sigmask, &sigsaved,
-                               sizeof(sigsaved));
-                       set_restore_sigmask();
-               }
-               ret = -ERESTARTNOHAND;
-       } else if (sigmask)
-               sigprocmask(SIG_SETMASK, &sigsaved, NULL);
-
-       ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
-
-       return ret;
-}
-
-#ifdef CONFIG_FHANDLE
-/*
- * Exactly like fs/open.c:sys_open_by_handle_at(), except that it
- * doesn't set the O_LARGEFILE flag.
- */
-COMPAT_SYSCALL_DEFINE3(open_by_handle_at, int, mountdirfd,
-                            struct file_handle __user *, handle, int, flags)
-{
-       return do_handle_open(mountdirfd, handle, flags);
-}
-#endif