Messages in this thread | | | Date | Sun, 24 May 2020 16:44:40 -0700 | Subject | Re: Re: [PATCH v12 00/18] Enable FSGSBASE instructions | From | hpa@zytor ... |
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On May 24, 2020 2:19:45 PM PDT, Sasha Levin <sashal@kernel.org> wrote: >On Sun, May 24, 2020 at 12:45:18PM -0700, hpa@zytor.com wrote: >>There are legitimate reasons to write a root-hole module, the main one >being able to test security features like SMAP. I have requested before >a TAINT flag specifically for this purpose, because TAINT_CRAP is >nowhere near explicit enough, and is also used for staging drivers. >Call it TAINT_TOXIC or TAINT_ROOTHOLE; it should always be accompanied >with a CRIT level alert. > >What I don't like about our current system of TAINT_* flags is that >while we can improve it as much as we want, no one outside of the >kernel >tree seems to be using it. While Thomas may have been commenting on >Graphene's behaviour, look at any other code that did the same thing: > >- Graphene: >https://github.com/oscarlab/graphene-sgx-driver/blob/master/gsgx.c >- Occlum: >https://github.com/occlum/enable_rdfsbase/blob/master/enable_rdfsbase.c >- SGX-LKL: >https://github.com/lsds/sgx-lkl/blob/master/tools/kmod-set-fsgsbase/mod_set_cr4_fsgsbase.c > >None of which set even the CRAP flag.
That's a separate problem, but I would personally want to have it for my own test modules in case one ever escapes. -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
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