Re: quotactl hook

From: Seth Arnold (sarnoldat_private)
Date: Wed Sep 05 2001 - 17:32:43 PDT

  • Next message: richard offer: "Re: quotactl hook"

    On Wed, Sep 05, 2001 at 04:47:36PM -0700, richard offer wrote:
    > And we'd still have to move the in-kernel code into the module to capture
    > the error code as there are places that return different errno's depending
    > on the code path.
    [..]
    >     vfs_permission()
    >     sys_setpriority()
    >     sys_setgroups()
    >     sys_sethostname()
    >     sys_setdomainname()
    
    Now, if I think I understand your needs, the four sys_set* functions
    here are being hooked for two reasons. The first is to provide some
    level of access control, the second is for the return values for an
    audit requirement. With these specific four, is the current hook
    insufficient for access control?
    
    I ask this primarily because system call interposition could be used to
    get the return value irrespective of the several different return values
    and short-circuit evaluations.. At least in these four cases.
    
    Of course, vfs_permission() isn't so easy to hand-waving fix. (As my
    tree doesn't even have a security_ops hook in vfs_permission, I'm not
    sure quite what the problem is -- the vfs_permission function only says
    that access is or is not granted, not what is done with that access once
    granted. So, I don't even see the audit potential..) 
    
    I *do* like the specific examples, though. :) I think they do a good job
    of communicating what is wrong with the current approach, as much as
    SGI's needs are concerned..
    
    _______________________________________________
    linux-security-module mailing list
    linux-security-moduleat_private
    http://mail.wirex.com/mailman/listinfo/linux-security-module
    



    This archive was generated by hypermail 2b30 : Wed Sep 05 2001 - 17:35:34 PDT