Message-ID: <e6a975ce-3880-1429-f013-40604e361c8f@schaufler-ca.com>
Date:   Fri, 10 Mar 2023 12:49:57 -0800
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Subject: Re: [PATCH v1 0/2] Add destructor hook to LSM modules
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To:     Mirsad Goran Todorovac <mirsad.goran.todorovac@alu.hr>,
        linux-kernel@vger.kernel.org
Cc:     linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        =?UTF-8?Q?Thomas_Wei=c3=9fschuh?= <linux@weissschuh.net>,
        Mimi Zohar <zohar@linux.ibm.com>,
        Paul Moore <paul@paul-moore.com>,
        =?UTF-8?Q?Christian_G=c3=b6ttsche?= <cgzones@googlemail.com>,
        =?UTF-8?Q?Micka=c3=abl_Sala=c3=bcn?= <mic@digikod.net>,
        Frederick Lawler <fred@cloudflare.com>, casey@schaufler-ca.com
References: <20230310192614.GA528@domac.alu.hr>
From:   Casey Schaufler <casey@schaufler-ca.com>
In-Reply-To: <20230310192614.GA528@domac.alu.hr>
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On 3/10/2023 11:26 AM, Mirsad Goran Todorovac wrote:
> LSM security/integrity/iint.c had the case of kmem_cache_create() w/o a proper
> kmem_cache_destroy() destructor.

LSMs should be using the security blobs associated with system objects
rather than doing their own memory management.

>
> Introducing the release() hook would enable LSMs to release allocated resources
> on exit, and in proper order, rather than dying all together with kernel shutdown
> in an undefined order.
>
> Thanks,
> 	Mirsad
>
> ---
>  include/linux/lsm_hooks.h | 1 +
>  security/integrity/iint.c | 7 +++++++
>  2 files changed, 8 insertions(+)
>
> --
> Mirsad Goran Todorovac
> Sistem inženjer
> Grafički fakultet | Akademija likovnih umjetnosti
> Sveučilište u Zagrebu
>  
> System engineer
> Faculty of Graphic Arts | Academy of Fine Arts
> University of Zagreb, Republic of Croatia
> The European Union