linux/fs/overlayfs
Christian Brauner 0558c1bf5a
capability: handle idmapped mounts
In order to determine whether a caller holds privilege over a given
inode the capability framework exposes the two helpers
privileged_wrt_inode_uidgid() and capable_wrt_inode_uidgid(). The former
verifies that the inode has a mapping in the caller's user namespace and
the latter additionally verifies that the caller has the requested
capability in their current user namespace.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped inodes. If the initial user namespace is passed all
operations are a nop so non-idmapped mounts will not see a change in
behavior.

Link: https://lore.kernel.org/r/20210121131959.646623-5-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
..
copy_up.c ovl: do not fail when setting origin xattr 2020-12-14 15:26:14 +01:00
dir.c ovl: pass ovl_fs down to functions accessing private xattrs 2020-09-02 10:58:49 +02:00
export.c ovl: propagate ovl_fs to ovl_decode_real_fh and ovl_encode_real_fh 2020-11-12 11:31:55 +01:00
file.c ovl: do not fail because of O_NOATIME 2020-12-14 15:26:14 +01:00
inode.c ovl: user xattr 2020-12-14 15:26:14 +01:00
Kconfig docs: fix broken references to text files 2020-04-20 15:35:59 -06:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
namei.c ovl: check privs before decoding file handle 2020-12-14 15:26:14 +01:00
overlayfs.h ovl: user xattr 2020-12-14 15:26:14 +01:00
ovl_entry.h ovl: user xattr 2020-12-14 15:26:14 +01:00
readdir.c ovl: support [S|G]ETFLAGS and FS[S|G]ETXATTR ioctls for directories 2020-10-06 15:38:14 +02:00
super.c capability: handle idmapped mounts 2021-01-24 14:27:16 +01:00
util.c ovl: do not get metacopy for userxattr 2020-12-14 15:26:14 +01:00