Re: [PATCH 0/7] overlayfs: fix ro/rw fd data inconsistecies

From: Miklos Szeredi
Date: Thu Nov 24 2016 - 09:14:50 EST


On Thu, Nov 24, 2016 at 11:55 AM, Miklos Szeredi <mszeredi@xxxxxxxxxx> wrote:
> A file is opened for read-only, opened read-write (resulting in a copy up)
> and modified. The data read back from the the read-only fd will be stale
> in this case (the read-only file descriptor still refers to the lower,
> unmodified file).
>
> This patchset fixes issues related to this corner case.
>
> The VFS impact is minimal and performance in the non-corner cases shouldn't
> suffer.

Git tree is here:

git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs.git #overlayfs-rorw

Thanks,
Miklos

> ---
> Miklos Szeredi (7):
> vfs: allow overlayfs to intercept file ops
> vfs: export filp_clone_open()
> mm: ovl: copy-up on MAP_SHARED
> ovl: add infrastructure for intercepting file ops
> ovl: intercept read_iter
> ovl: intercept mmap
> ovl: intercept fsync
>
> fs/internal.h | 1 -
> fs/open.c | 2 +-
> fs/overlayfs/inode.c | 225 +++++++++++++++++++++++++++++++++++++++++++++++
> fs/overlayfs/overlayfs.h | 2 +
> fs/overlayfs/super.c | 1 +
> include/linux/fs.h | 1 +
> mm/util.c | 22 +++++
> 7 files changed, 252 insertions(+), 2 deletions(-)
>
> --
> 2.5.5
>