Re: [TOMOYO #9 (2.6.27-rc7-mm1) 1/6] LSM adapter functions.

Kentaro Takeda
2008-10-06T02:19:51Z

Serge E. Hallyn wrote:
> Why can't you just clear the value during security_inode_foo()?
We need a new hook for clearing the value since security_inode_*()
are not always called after security_path_*() .

> Note I'm seeing this as a way for Tomoyo to temporarily (maybe) work
> around the mis-placement of the security_path_foo() hooks. I don't want
> to add security_path_clear() hooks to "legitimize" the workaround. I'd
> rather Tomoyo and Apparmor folks keep looking for a better way to get
> real DAC-before-MAC.
Hmm, I can understand your opinion. The best way for AppArmor and
TOMOYO is to pass vfsmount to vfs_*() and security_inode_*() . This
approach has no DAC-before-MAC problem. However, it is clearly
opposed by Al because of layering. So, we are going forward
security_path_*() approach, which Al advised us.

Since vfsmount is only available outside vfs_*() (and vfs_*() perform
DAC), we cannot conceive another place now... Where do you think the
right place to introduce security_path_*() hooks is?

Regards,