Re: [PATCH] lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()

On Fri, Nov 19, 2021 at 6:59 PM John Johansen
[off-list ref] wrote:

On 11/19/21 3:23 PM, Serge E. Hallyn wrote:

quoted

On Fri, Nov 19, 2021 at 05:52:33PM -0500, Paul Moore wrote:

quoted

On Wed, Sep 29, 2021 at 3:17 PM Paul Moore [off-list ref] wrote:

quoted

The security_task_getsecid_subj() LSM hook invites misuse by allowing
callers to specify a task even though the hook is only safe when the
current task is referenced.  Fix this by removing the task_struct
argument to the hook, requiring LSM implementations to use the
current task.  While we are changing the hook declaration we also
rename the function to security_current_getsecid_subj() in an effort
to reinforce that the hook captures the subjective credentials of the
current task and not an arbitrary task on the system.

Signed-off-by: Paul Moore <paul@paul-moore.com>

Makes perfect sense given the motivation of 4ebd7651b  :)

Reviewed-by: Serge Hallyn <serge@hallyn.com>

Oh, actually, one question below (cc:ing John explicitly)

<< snip >>

quoted

quoted

quoted

-static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
+static void apparmor_current_getsecid_subj(u32 *secid)
+{
+       struct aa_label *label = aa_get_task_label(current);

Should you use aa_get_current_label() here instead?

yes, that would be better

Will do, thanks guys.

-- 
paul moore
www.paul-moore.com