security,overlayfs: Provide security hook for copy up of xattrs for overlay file

Provide a security hook which is called when xattrs of a file are being
copied up. This hook is called once for each xattr and LSM can return
0 if the security module wants the xattr to be copied up, 1 if the
security module wants the xattr to be discarded on the copy, -EOPNOTSUPP
if the security module does not handle/manage the xattr, or a -errno
upon an error.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: whitespace cleanup for checkpatch.pl]
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Vivek Goyal
2016-07-13 10:44:49 -04:00
committed by Paul Moore
parent 56909eb3f5
commit 121ab822ef
4 changed files with 31 additions and 0 deletions

View File

@ -754,6 +754,12 @@ int security_inode_copy_up(struct dentry *src, struct cred **new)
}
EXPORT_SYMBOL(security_inode_copy_up);
int security_inode_copy_up_xattr(const char *name)
{
return call_int_hook(inode_copy_up_xattr, -EOPNOTSUPP, name);
}
EXPORT_SYMBOL(security_inode_copy_up_xattr);
int security_file_permission(struct file *file, int mask)
{
int ret;
@ -1692,6 +1698,8 @@ struct security_hook_heads security_hook_heads = {
LIST_HEAD_INIT(security_hook_heads.inode_getsecid),
.inode_copy_up =
LIST_HEAD_INIT(security_hook_heads.inode_copy_up),
.inode_copy_up_xattr =
LIST_HEAD_INIT(security_hook_heads.inode_copy_up_xattr),
.file_permission =
LIST_HEAD_INIT(security_hook_heads.file_permission),
.file_alloc_security =