9636e70ee2
[ Upstream commit 2878dffc7db0b5a51e308ccb6b571296b57c82e7 ]
When copying inode attributes from the upper or lower layer to ovl inodes
we need to take the upper or lower layer's mount's idmapping into
account. In a lot of places we call ovl_copyattr() only on upper inodes and
in some we call it on either upper or lower inodes. Split this into two
separate helpers.
The first one should only be called on upper
inodes and is thus called ovl_copy_upperattr(). The second one can be
called on upper or lower inodes. We add ovl_copy_realattr() for this
task. The new helper makes use of the previously added ovl_i_path_real()
helper. This is needed to support idmapped base layers with overlay.
When overlay copies the inode information from an upper or lower layer
to the relevant overlay inode it will apply the idmapping of the upper
or lower layer when doing so. The ovl inode ownership will thus always
correctly reflect the ownership of the idmapped upper or lower layer.
All idmapping helpers are nops when no idmapped base layers are used.
Cc: <linux-unionfs@vger.kernel.org>
Tested-by: Giuseppe Scrivano <gscrivan@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Stable-dep-of: b306e90ffabd ("ovl: remove privs in ovl_copyfile()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.