linux/fs/ocfs2/ioctl.c
Satyam Sharma 3bd858ab1c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check
Introduce is_owner_or_cap() macro in fs.h, and convert over relevant
users to it. This is done because we want to avoid bugs in the future
where we check for only effective fsuid of the current task against a
file's owning uid, without simultaneously checking for CAP_FOWNER as
well, thus violating its semantics.
[ XFS uses special macros and structures, and in general looked ...
untouchable, so we leave it alone -- but it has been looked over. ]

The (current->fsuid != inode->i_uid) check in generic_permission() and
exec_permission_lite() is left alone, because those operations are
covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations
falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone.

Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 12:00:03 -07:00

175 lines
3.5 KiB
C

/*
* linux/fs/ocfs2/ioctl.c
*
* Copyright (C) 2006 Herbert Poetzl
* adapted from Remy Card's ext2/ioctl.c
*/
#include <linux/fs.h>
#include <linux/mount.h>
#define MLOG_MASK_PREFIX ML_INODE
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "dlmglue.h"
#include "file.h"
#include "inode.h"
#include "journal.h"
#include "ocfs2_fs.h"
#include "ioctl.h"
#include <linux/ext2_fs.h>
static int ocfs2_get_inode_attr(struct inode *inode, unsigned *flags)
{
int status;
status = ocfs2_meta_lock(inode, NULL, 0);
if (status < 0) {
mlog_errno(status);
return status;
}
ocfs2_get_inode_flags(OCFS2_I(inode));
*flags = OCFS2_I(inode)->ip_attr;
ocfs2_meta_unlock(inode, 0);
mlog_exit(status);
return status;
}
static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
unsigned mask)
{
struct ocfs2_inode_info *ocfs2_inode = OCFS2_I(inode);
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
handle_t *handle = NULL;
struct buffer_head *bh = NULL;
unsigned oldflags;
int status;
mutex_lock(&inode->i_mutex);
status = ocfs2_meta_lock(inode, &bh, 1);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = -EROFS;
if (IS_RDONLY(inode))
goto bail_unlock;
status = -EACCES;
if (!is_owner_or_cap(inode))
goto bail_unlock;
if (!S_ISDIR(inode->i_mode))
flags &= ~OCFS2_DIRSYNC_FL;
handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
mlog_errno(status);
goto bail_unlock;
}
oldflags = ocfs2_inode->ip_attr;
flags = flags & mask;
flags |= oldflags & ~mask;
/*
* The IMMUTABLE and APPEND_ONLY flags can only be changed by
* the relevant capability.
*/
status = -EPERM;
if ((oldflags & OCFS2_IMMUTABLE_FL) || ((flags ^ oldflags) &
(OCFS2_APPEND_FL | OCFS2_IMMUTABLE_FL))) {
if (!capable(CAP_LINUX_IMMUTABLE))
goto bail_unlock;
}
ocfs2_inode->ip_attr = flags;
ocfs2_set_inode_flags(inode);
status = ocfs2_mark_inode_dirty(handle, inode, bh);
if (status < 0)
mlog_errno(status);
ocfs2_commit_trans(osb, handle);
bail_unlock:
ocfs2_meta_unlock(inode, 1);
bail:
mutex_unlock(&inode->i_mutex);
if (bh)
brelse(bh);
mlog_exit(status);
return status;
}
int ocfs2_ioctl(struct inode * inode, struct file * filp,
unsigned int cmd, unsigned long arg)
{
unsigned int flags;
int status;
struct ocfs2_space_resv sr;
switch (cmd) {
case OCFS2_IOC_GETFLAGS:
status = ocfs2_get_inode_attr(inode, &flags);
if (status < 0)
return status;
flags &= OCFS2_FL_VISIBLE;
return put_user(flags, (int __user *) arg);
case OCFS2_IOC_SETFLAGS:
if (get_user(flags, (int __user *) arg))
return -EFAULT;
return ocfs2_set_inode_attr(inode, flags,
OCFS2_FL_MODIFIABLE);
case OCFS2_IOC_RESVSP:
case OCFS2_IOC_RESVSP64:
case OCFS2_IOC_UNRESVSP:
case OCFS2_IOC_UNRESVSP64:
if (copy_from_user(&sr, (int __user *) arg, sizeof(sr)))
return -EFAULT;
return ocfs2_change_file_space(filp, cmd, &sr);
default:
return -ENOTTY;
}
}
#ifdef CONFIG_COMPAT
long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
struct inode *inode = file->f_path.dentry->d_inode;
int ret;
switch (cmd) {
case OCFS2_IOC32_GETFLAGS:
cmd = OCFS2_IOC_GETFLAGS;
break;
case OCFS2_IOC32_SETFLAGS:
cmd = OCFS2_IOC_SETFLAGS;
break;
case OCFS2_IOC_RESVSP:
case OCFS2_IOC_RESVSP64:
case OCFS2_IOC_UNRESVSP:
case OCFS2_IOC_UNRESVSP64:
break;
default:
return -ENOIOCTLCMD;
}
lock_kernel();
ret = ocfs2_ioctl(inode, file, cmd, arg);
unlock_kernel();
return ret;
}
#endif