linux/arch/parisc/hpux/fs.c
Jeff Layton 91a27b2a75 vfs: define struct filename and have getname() return it
getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 20:14:55 -04:00

205 lines
5.1 KiB
C

/*
* Implements HPUX syscalls.
*
* Copyright (C) 1999 Matthew Wilcox <willy with parisc-linux.org>
* Copyright (C) 2000 Michael Ang <mang with subcarrier.org>
* Copyright (C) 2000 John Marvin <jsm with parisc-linux.org>
* Copyright (C) 2000 Philipp Rumpf
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/file.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <asm/errno.h>
#include <asm/uaccess.h>
int hpux_execve(struct pt_regs *regs)
{
int error;
struct filename *filename;
filename = getname((const char __user *) regs->gr[26]);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename->name,
(const char __user *const __user *) regs->gr[25],
(const char __user *const __user *) regs->gr[24],
regs);
putname(filename);
out:
return error;
}
struct hpux_dirent {
loff_t d_off;
ino_t d_ino;
short d_reclen;
short d_namlen;
char d_name[1];
};
struct getdents_callback {
struct hpux_dirent __user *current_dir;
struct hpux_dirent __user *previous;
int count;
int error;
};
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char __user *) (de)))
static int filldir(void * __buf, const char * name, int namlen, loff_t offset,
u64 ino, unsigned d_type)
{
struct hpux_dirent __user * dirent;
struct getdents_callback * buf = (struct getdents_callback *) __buf;
ino_t d_ino;
int reclen = ALIGN(NAME_OFFSET(dirent) + namlen + 1, sizeof(long));
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 (put_user(offset, &dirent->d_off))
goto Efault;
dirent = buf->current_dir;
if (put_user(d_ino, &dirent->d_ino) ||
put_user(reclen, &dirent->d_reclen) ||
put_user(namlen, &dirent->d_namlen) ||
copy_to_user(dirent->d_name, name, namlen) ||
put_user(0, dirent->d_name + namlen))
goto Efault;
buf->previous = dirent;
buf->current_dir = (void __user *)dirent + reclen;
buf->count -= reclen;
return 0;
Efault:
buf->error = -EFAULT;
return -EFAULT;
}
#undef NAME_OFFSET
int hpux_getdents(unsigned int fd, struct hpux_dirent __user *dirent, unsigned int count)
{
struct fd arg;
struct hpux_dirent __user * lastdirent;
struct getdents_callback buf;
int error;
arg = fdget(fd);
if (!arg.file)
return -EBADF;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(arg.file, filldir, &buf);
if (error >= 0)
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
if (put_user(arg.file->f_pos, &lastdirent->d_off))
error = -EFAULT;
else
error = count - buf.count;
}
fdput(arg);
return error;
}
int hpux_mount(const char *fs, const char *path, int mflag,
const char *fstype, const char *dataptr, int datalen)
{
return -ENOSYS;
}
static int cp_hpux_stat(struct kstat *stat, struct hpux_stat64 __user *statbuf)
{
struct hpux_stat64 tmp;
/* we probably want a different split here - is hpux 12:20? */
if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
return -EOVERFLOW;
memset(&tmp, 0, sizeof(tmp));
tmp.st_dev = new_encode_dev(stat->dev);
tmp.st_ino = stat->ino;
tmp.st_mode = stat->mode;
tmp.st_nlink = stat->nlink;
tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
tmp.st_rdev = new_encode_dev(stat->rdev);
tmp.st_size = stat->size;
tmp.st_atime = stat->atime.tv_sec;
tmp.st_mtime = stat->mtime.tv_sec;
tmp.st_ctime = stat->ctime.tv_sec;
tmp.st_blocks = stat->blocks;
tmp.st_blksize = stat->blksize;
return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}
long hpux_stat64(const char __user *filename, struct hpux_stat64 __user *statbuf)
{
struct kstat stat;
int error = vfs_stat(filename, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}
long hpux_fstat64(unsigned int fd, struct hpux_stat64 __user *statbuf)
{
struct kstat stat;
int error = vfs_fstat(fd, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}
long hpux_lstat64(const char __user *filename,
struct hpux_stat64 __user *statbuf)
{
struct kstat stat;
int error = vfs_lstat(filename, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}