selinux: only filter copy-up xattrs following initialization

Extended attribute copy-up functionality added via 19472b69d6
("selinux: Implementation for inode_copy_up_xattr() hook") sees
"security.selinux" contexts dropped, instead relying on contexts
applied via the inode_copy_up() hook.

When copy-up takes place during early boot, prior to selinux
initialization / policy load, the context stripping can be unwanted
and unexpected.

With this change, filtering of "security.selinux" xattrs will only occur
after selinux initialization.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
David Disseldorp 2024-02-02 17:40:48 +11:00 committed by Paul Moore
parent bfda63fa22
commit 7c655bee5c

View File

@ -3533,9 +3533,10 @@ static int selinux_inode_copy_up_xattr(const char *name)
{
/* The copy_up hook above sets the initial context on an inode, but we
* don't then want to overwrite it by blindly copying all the lower
* xattrs up. Instead, we have to filter out SELinux-related xattrs.
* xattrs up. Instead, filter out SELinux-related xattrs following
* policy load.
*/
if (strcmp(name, XATTR_NAME_SELINUX) == 0)
if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
return 1; /* Discard */
/*
* Any other attribute apart from SELINUX is not claimed, supported