Messages in this thread | | | From | Kees Cook <> | Date | Thu, 16 Nov 2017 17:08:57 -0800 | Subject | Re: [PATCH v2 00/15] ima: digest list feature |
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On Tue, Nov 7, 2017 at 8:45 AM, Roberto Sassu <roberto.sassu@huawei.com> wrote: > On 11/7/2017 2:37 PM, Mimi Zohar wrote: >> Normally, the protection of kernel memory is out of scope for IMA. >> This patch set introduces an in kernel white list, which would be a >> prime target for attackers looking for ways of by-passing IMA- >> measurement, IMA-appraisal and IMA-audit. Others might disagree, but >> from my perspective, this risk is too high.
BTW, which part of the series does the whitelist? I'd agree generally, though: we don't want to make things writable if they're normally read-only.
> It would be much easier for an attacker to just set ima_policy_flag to > zero.
That's a fair point. I wonder if ima_policy_flag could be marked __ro_after_init? Most of the writes are from __init sections, but I haven't looked closely at when ima_update_policy() gets called.
-Kees
-- Kees Cook Pixel Security
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