On Tue, 2009-03-17 at 13:23 -0500, Serge E. Hallyn wrote: > But in cap_inode_setxattr, any security.* xattrs are controlled by > CAP_SYS_ADMIN. So do you think that this should be changed to a > CAP_XATTR_SECURITY capability which can be added to CAP_FS_MASK? I think that would be preferable to CAP_SYS_ADMIN, yes. > Or do you think it's ok that fsuid=0 does not allow you to set > security.selinux (or security.SMACK64, etc) xattrs when selinux is > not compiled in? Just to be clear, at present fsuid is irrelevant to setting the security.* xattrs since it doesn't affect the CAP_SYS_ADMIN capability at all, so it all depends on the initial capability state prior to using setfsuid(), typically the full capability set. > (You may have already answered this with your EOPNOTSUPP comment, but > I want to make sure I understand right) > > > > Does anyone know what the trusted xattrs are used for? > > > > Not beyond what attr(5) says about them. > > Well, if attr(5) says CAP_SYS_ADMIN being needed is the very > thing that defines these xattrs, then changing that seems a > bigger deal. That really does seem akin to changing kernel-user > API. Perhaps, although it isn't clear that this API is in use by anyone or in use in a way that would actually distinguish based on individual capability. But if you were to add CAP_SYS_ADMIN to CAP_FS_MASK in order to ensure that setfsuid() does in fact affect all filesystem accesses, how much meaningful difference remains between fsuid==0 and euid==0? It obviously takes you far afield of only affecting filesystem accesses. -- Stephen Smalley National Security Agency -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@xxxxxxxxxxxxx with the words "unsubscribe selinux" without quotes as the message.
