diff options
| author | Tycho Andersen <tycho@tycho.pizza> | 2021-01-21 14:19:28 +0100 |
|---|---|---|
| committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:17 +0100 |
| commit | c7c7a1a18af4c3bb7749d33e3df3acdf0a95bbb5 (patch) | |
| tree | 70987010043f447700ed119e1b05b8fb429af5dd /fs/overlayfs/super.c | |
| parent | e65ce2a50cf6af216bea6fd80d771fcbb4c0aaa1 (diff) | |
xattr: handle idmapped mounts
When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.
Link: https://lore.kernel.org/r/20210121131959.646623-10-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>
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index e24c995c5fd4..8168ab2dda11 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -794,11 +794,13 @@ retry: * allowed as upper are limited to "normal" ones, where checking * for the above two errors is sufficient. */ - err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_DEFAULT); + err = vfs_removexattr(&init_user_ns, work, + XATTR_NAME_POSIX_ACL_DEFAULT); if (err && err != -ENODATA && err != -EOPNOTSUPP) goto out_dput; - err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_ACCESS); + err = vfs_removexattr(&init_user_ns, work, + XATTR_NAME_POSIX_ACL_ACCESS); if (err && err != -ENODATA && err != -EOPNOTSUPP) goto out_dput; |