android_kernel_samsung_msm8976/fs/hfsplus/ioctl.c
Dave Hansen 42a74f206b [PATCH] r/o bind mounts: elevate write count for ioctls()
Some ioctl()s can cause writes to the filesystem.  Take these, and make them
use mnt_want/drop_write() instead.

[AV: updated]

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:24 -04:00

198 lines
5 KiB
C

/*
* linux/fs/hfsplus/ioctl.c
*
* Copyright (C) 2003
* Ethan Benson <erbenson@alaska.net>
* partially derived from linux/fs/ext2/ioctl.c
* Copyright (C) 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* hfsplus ioctls
*/
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/xattr.h>
#include <asm/uaccess.h>
#include "hfsplus_fs.h"
int hfsplus_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
unsigned long arg)
{
unsigned int flags;
switch (cmd) {
case HFSPLUS_IOC_EXT2_GETFLAGS:
flags = 0;
if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_IMMUTABLE)
flags |= FS_IMMUTABLE_FL; /* EXT2_IMMUTABLE_FL */
if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_APPEND)
flags |= FS_APPEND_FL; /* EXT2_APPEND_FL */
if (HFSPLUS_I(inode).userflags & HFSPLUS_FLG_NODUMP)
flags |= FS_NODUMP_FL; /* EXT2_NODUMP_FL */
return put_user(flags, (int __user *)arg);
case HFSPLUS_IOC_EXT2_SETFLAGS: {
int err = 0;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
if (!is_owner_or_cap(inode)) {
err = -EACCES;
goto setflags_out;
}
if (get_user(flags, (int __user *)arg)) {
err = -EFAULT;
goto setflags_out;
}
if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
if (!capable(CAP_LINUX_IMMUTABLE)) {
err = -EPERM;
goto setflags_out;
}
}
/* don't silently ignore unsupported ext2 flags */
if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
err = -EOPNOTSUPP;
goto setflags_out;
}
if (flags & FS_IMMUTABLE_FL) { /* EXT2_IMMUTABLE_FL */
inode->i_flags |= S_IMMUTABLE;
HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_IMMUTABLE;
} else {
inode->i_flags &= ~S_IMMUTABLE;
HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_IMMUTABLE;
}
if (flags & FS_APPEND_FL) { /* EXT2_APPEND_FL */
inode->i_flags |= S_APPEND;
HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_APPEND;
} else {
inode->i_flags &= ~S_APPEND;
HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_APPEND;
}
if (flags & FS_NODUMP_FL) /* EXT2_NODUMP_FL */
HFSPLUS_I(inode).userflags |= HFSPLUS_FLG_NODUMP;
else
HFSPLUS_I(inode).userflags &= ~HFSPLUS_FLG_NODUMP;
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
setflags_out:
mnt_drop_write(filp->f_path.mnt);
return err;
}
default:
return -ENOTTY;
}
}
int hfsplus_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct inode *inode = dentry->d_inode;
struct hfs_find_data fd;
hfsplus_cat_entry entry;
struct hfsplus_cat_file *file;
int res;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
res = hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
if (res)
return res;
res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
if (res)
goto out;
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
file = &entry.file;
if (!strcmp(name, "hfs.type")) {
if (size == 4)
memcpy(&file->user_info.fdType, value, 4);
else
res = -ERANGE;
} else if (!strcmp(name, "hfs.creator")) {
if (size == 4)
memcpy(&file->user_info.fdCreator, value, 4);
else
res = -ERANGE;
} else
res = -EOPNOTSUPP;
if (!res)
hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
out:
hfs_find_exit(&fd);
return res;
}
ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
void *value, size_t size)
{
struct inode *inode = dentry->d_inode;
struct hfs_find_data fd;
hfsplus_cat_entry entry;
struct hfsplus_cat_file *file;
ssize_t res = 0;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
if (size) {
res = hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
if (res)
return res;
res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
if (res)
goto out;
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
}
file = &entry.file;
if (!strcmp(name, "hfs.type")) {
if (size >= 4) {
memcpy(value, &file->user_info.fdType, 4);
res = 4;
} else
res = size ? -ERANGE : 4;
} else if (!strcmp(name, "hfs.creator")) {
if (size >= 4) {
memcpy(value, &file->user_info.fdCreator, 4);
res = 4;
} else
res = size ? -ERANGE : 4;
} else
res = -ENODATA;
out:
if (size)
hfs_find_exit(&fd);
return res;
}
#define HFSPLUS_ATTRLIST_SIZE (sizeof("hfs.creator")+sizeof("hfs.type"))
ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
struct inode *inode = dentry->d_inode;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
if (!buffer || !size)
return HFSPLUS_ATTRLIST_SIZE;
if (size < HFSPLUS_ATTRLIST_SIZE)
return -ERANGE;
strcpy(buffer, "hfs.type");
strcpy(buffer + sizeof("hfs.type"), "hfs.creator");
return HFSPLUS_ATTRLIST_SIZE;
}