linux/fs/overlayfs
Miklos Szeredi d0e13f5bbe ovl: fix uid/gid when creating over whiteout
Fix a regression when creating a file over a whiteout.  The new
file/directory needs to use the current fsuid/fsgid, not the ones from the
mounter's credentials.

The refcounting is a bit tricky: prepare_creds() sets an original refcount,
override_creds() gets one more, which revert_cred() drops.  So

  1) we need to expicitly put the mounter's credentials when overriding
     with the updated one

  2) we need to put the original ref to the updated creds (and this can
     safely be done before revert_creds(), since we'll still have the ref
     from override_creds()).

Reported-by: Stephen Smalley <sds@tycho.nsa.gov>
Fixes: 3fe6e52f06 ("ovl: override creds with the ones from the superblock mounter")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-06-15 14:18:59 +02:00
..
Kconfig ovl: rename filesystem type to "overlay" 2014-11-20 16:39:59 +01:00
Makefile ovl: rename filesystem type to "overlay" 2014-11-20 16:39:59 +01:00
copy_up.c ovl: override creds with the ones from the superblock mounter 2016-05-27 08:55:26 +02:00
dir.c ovl: fix uid/gid when creating over whiteout 2016-06-15 14:18:59 +02:00
inode.c ovl: xattr filter fix 2016-06-06 16:21:37 +02:00
overlayfs.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
readdir.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-05-27 17:14:05 -07:00
super.c Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-05-27 16:44:39 -07:00