Re: Why hooks in sys_iopl and sys_ioperm?

From: Chris Wright (chrisat_private)
Date: Thu Jul 25 2002 - 00:51:22 PDT

  • Next message: Chris Wright: "Re: new hook for do_sys_settimeofday"

    * Emily Ratliff (ratliffat_private) wrote:
    > > The fact that SELinux presently does not use some of the "system" hooks
    > > should not be taken to mean that we don't consider these hooks to
    > > be useful.
    > That is fine. I included the reference to SELinux to point out that I 
    > checked to see if any of the current modules have potentially dangerous 
    > behavior in this area and I was surprise to find none of them actually 
    > using the hooks, esp. given the original design goal of only putting in 
    > hooks that projects are using. 
    
    I think this is a case where it was clear that CAP_SYS_RAWIO is just
    insufficient, and the hook felt obvious.
    
    > > These "system" hooks can support finer-grained control than the capability
    > > check.  As you note, the iopl and ioperm hooks are architecture-specific
    > > (even differing in the ia64 case, where ioperm merely calls iopl), but I
    > > don't think that necessarily means that they should be removed.
    > I am not necessarily calling for their removal. But, if they stay, I would 
    > just like to see something like the following:
    
    I don't mind making a useful note in the interface.  On the flip side,
    is there any better abstraction for mmap'd io?  /dev/mem, /dev/kmem,
    /dev/ports, and /proc/bus/pci all are protected with CAP_SYS_RAWIO.
    Anyway we can handle this at better granularity?
    
    thanks,
    -chris
    -- 
    Linux Security Modules     http://lsm.immunix.org     http://lsm.bkbits.net
    _______________________________________________
    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 : Thu Jul 25 2002 - 00:52:45 PDT