linux-stable/fs/cifs/ioctl.c
Jeff Layton 618763958b cifs: make cifs_ioctl handle NULL filp->private_data correctly
Commit 13cfb7334e made cifs_ioctl use the tlink attached to the
cifsFileInfo for a filp. This ignores the case of an open directory
however, which in CIFS can have a NULL private_data until a readdir
is done on it.

This patch re-adds the NULL pointer checks that were removed in commit
50ae28f01 and moves the setting of tcon and "caps" variables lower.

Long term, a better fix would be to establish a f_op->open routine for
directories that populates that field at open time, but that requires
some other changes to how readdir calls are handled.

Reported-by: Kjell Rune Skaaraas <kjella79@yahoo.no>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-08 18:56:36 +00:00

102 lines
2.8 KiB
C

/*
* fs/cifs/ioctl.c
*
* vfs operations that deal with io control
*
* Copyright (C) International Business Machines Corp., 2005,2007
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifsfs.h"
#define CIFS_IOC_CHECKUMOUNT _IO(0xCF, 2)
long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
{
struct inode *inode = filep->f_dentry->d_inode;
int rc = -ENOTTY; /* strange error - but the precedent */
int xid;
struct cifs_sb_info *cifs_sb;
#ifdef CONFIG_CIFS_POSIX
struct cifsFileInfo *pSMBFile = filep->private_data;
struct cifsTconInfo *tcon;
__u64 ExtAttrBits = 0;
__u64 ExtAttrMask = 0;
__u64 caps;
#endif /* CONFIG_CIFS_POSIX */
xid = GetXid();
cFYI(1, "ioctl file %p cmd %u arg %lu", filep, command, arg);
cifs_sb = CIFS_SB(inode->i_sb);
switch (command) {
case CIFS_IOC_CHECKUMOUNT:
cFYI(1, "User unmount attempted");
if (cifs_sb->mnt_uid == current_uid())
rc = 0;
else {
rc = -EACCES;
cFYI(1, "uids do not match");
}
break;
#ifdef CONFIG_CIFS_POSIX
case FS_IOC_GETFLAGS:
if (pSMBFile == NULL)
break;
tcon = tlink_tcon(pSMBFile->tlink);
caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
if (CIFS_UNIX_EXTATTR_CAP & caps) {
rc = CIFSGetExtAttr(xid, tcon, pSMBFile->netfid,
&ExtAttrBits, &ExtAttrMask);
if (rc == 0)
rc = put_user(ExtAttrBits &
FS_FL_USER_VISIBLE,
(int __user *)arg);
}
break;
case FS_IOC_SETFLAGS:
if (pSMBFile == NULL)
break;
tcon = tlink_tcon(pSMBFile->tlink);
caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
if (CIFS_UNIX_EXTATTR_CAP & caps) {
if (get_user(ExtAttrBits, (int __user *)arg)) {
rc = -EFAULT;
break;
}
/* rc= CIFSGetExtAttr(xid,tcon,pSMBFile->netfid,
extAttrBits, &ExtAttrMask);*/
}
cFYI(1, "set flags not implemented yet");
break;
#endif /* CONFIG_CIFS_POSIX */
default:
cFYI(1, "unsupported ioctl");
break;
}
FreeXid(xid);
return rc;
}