4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vivek Goyal <vgo...@redhat.com>
commit 07a2daab49c549a37b5b744cbebb6e3f445f12bc upstream.
Right now when a new overlay inode is created, we initialize overlay
inode's ->i_mode from underlying inode ->i_mode but we retain only
file type bits (S_IFMT) and discard permission bits.
This patch changes it and retains permission bits too. This should allow
overlay to do permission checks on overlay inode itself in task context.
[SzM] It also fixes clearing suid/sgid bits on write.
Signed-off-by: Vivek Goyal <vgo...@redhat.com>
Reported-by: Eryu Guan <eg...@redhat.com>
Signed-off-by: Miklos Szeredi <mszer...@redhat.com>
Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and
f_inode to the underlay")
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
fs/overlayfs/inode.c | 3 +--
fs/overlayfs/overlayfs.h | 1 +
2 files changed, 2 insertions(+), 2 deletions(-)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -412,12 +412,11 @@ struct inode *ovl_new_inode(struct super
if (!inode)
return NULL;
- mode &= S_IFMT;
-
inode->i_ino = get_next_ino();
inode->i_mode = mode;
inode->i_flags |= S_NOATIME | S_NOCMTIME;
+ mode &= S_IFMT;
switch (mode) {
case S_IFDIR:
inode->i_private = oe;
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -181,6 +181,7 @@ static inline void ovl_copyattr(struct i
{
to->i_uid = from->i_uid;
to->i_gid = from->i_gid;
+ to->i_mode = from->i_mode;
}
/* dir.c */
