eCryptfs: Clear LOOKUP_OPEN flag when creating lower file

eCryptfs was passing the LOOKUP_OPEN flag through to the lower file
system, even though ecryptfs_create() doesn't support the flag. A valid
filp for the lower filesystem could be returned in the nameidata if the
lower file system's create() function supported LOOKUP_OPEN, possibly
resulting in unencrypted writes to the lower file.

However, this is only a potential problem in filesystems (FUSE, NFS,
CIFS, CEPH, 9p) that eCryptfs isn't known to support today.

https://bugs.launchpad.net/ecryptfs/+bug/641703

Reported-by: Kevin Buhr
Cc: stable <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
This commit is contained in:
Tyler Hicks 2010-09-23 02:35:04 -05:00
parent 48b512e685
commit 2e21b3f124
1 changed files with 4 additions and 0 deletions

View File

@ -71,15 +71,19 @@ ecryptfs_create_underlying_file(struct inode *lower_dir_inode,
struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
struct dentry *dentry_save;
struct vfsmount *vfsmount_save;
unsigned int flags_save;
int rc;
dentry_save = nd->path.dentry;
vfsmount_save = nd->path.mnt;
flags_save = nd->flags;
nd->path.dentry = lower_dentry;
nd->path.mnt = lower_mnt;
nd->flags &= ~LOOKUP_OPEN;
rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
nd->path.dentry = dentry_save;
nd->path.mnt = vfsmount_save;
nd->flags = flags_save;
return rc;
}