releases/2.6.36.2/ecryptfs-clear-lookup_open-flag-when-creating-lower-file.patch

   1 From 2e21b3f124eceb6ab5a07c8a061adce14ac94e14 Mon Sep 17 00:00:00 2001
   2 From: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
   3 Date: Thu, 23 Sep 2010 02:35:04 -0500
   4 Subject: eCryptfs: Clear LOOKUP_OPEN flag when creating lower file
   5
   6 From: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
   7
   8 commit 2e21b3f124eceb6ab5a07c8a061adce14ac94e14 upstream.
   9
  10 eCryptfs was passing the LOOKUP_OPEN flag through to the lower file
  11 system, even though ecryptfs_create() doesn't support the flag. A valid
  12 filp for the lower filesystem could be returned in the nameidata if the
  13 lower file system's create() function supported LOOKUP_OPEN, possibly
  14 resulting in unencrypted writes to the lower file.
  15
  16 However, this is only a potential problem in filesystems (FUSE, NFS,
  17 CIFS, CEPH, 9p) that eCryptfs isn't known to support today.
  18
  19 https://bugs.launchpad.net/ecryptfs/+bug/641703
  20
  21 Reported-by: Kevin Buhr
  22 Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
  23 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  24
  25 ---
  26  fs/ecryptfs/inode.c |    4 ++++
  27  1 file changed, 4 insertions(+)
  28
  29 --- a/fs/ecryptfs/inode.c
  30 +++ b/fs/ecryptfs/inode.c
  31 @@ -70,15 +70,19 @@ ecryptfs_create_underlying_file(struct i
  32         struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
  33         struct dentry *dentry_save;
  34         struct vfsmount *vfsmount_save;
  35 +       unsigned int flags_save;
  36         int rc;
  37
  38         dentry_save = nd->path.dentry;
  39         vfsmount_save = nd->path.mnt;
  40 +       flags_save = nd->flags;
  41         nd->path.dentry = lower_dentry;
  42         nd->path.mnt = lower_mnt;
  43 +       nd->flags &= ~LOOKUP_OPEN;
  44         rc = vfs_create(lower_dir_inode, lower_dentry, mode, nd);
  45         nd->path.dentry = dentry_save;
  46         nd->path.mnt = vfsmount_save;
  47 +       nd->flags = flags_save;
  48         return rc;
  49  }
  50