Re: [RFC 0/2] ima: evm: Add kernel cmdline options to disable IMA/EVM

[Mimi Zohar <zohar@linux.ibm.com>]

On Tue, 2024-12-17 at 13:29 -0800, Casey Schaufler wrote:
> On 12/17/2024 12:25 PM, Song Liu wrote:
> > While reading and testing LSM code, I found IMA/EVM consume per inode
> > storage even when they are not in use. Add options to diable them in
> > kernel command line. The logic and syntax is mostly borrowed from an
> > old serious [1].
> 
> Why not omit ima and evm from the lsm= parameter?

Casey, Paul, always enabling IMA & EVM as the last LSMs, if configured, were the
conditions for making IMA and EVM LSMs.  Up to that point, only when an inode
was in policy did it consume any memory (rbtree).  I'm pretty sure you remember
the rather heated discussion(s).

Mimi

> 
> > 
> > [1] https://lore.kernel.org/lkml/cover.1398259638.git.d.kasatkin@samsung.com/
> > 
> > Song Liu (2):
> >   ima: Add kernel parameter to disable IMA
> >   evm: Add kernel parameter to disable EVM
> > 
> >  security/integrity/evm/evm.h       |  6 ++++++
> >  security/integrity/evm/evm_main.c  | 22 ++++++++++++++--------
> >  security/integrity/evm/evm_secfs.c |  3 ++-
> >  security/integrity/ima/ima_main.c  | 13 +++++++++++++
> >  4 files changed, 35 insertions(+), 9 deletions(-)
> > 
> > --
> > 2.43.5
> > 
>