Messages in this thread | | | Date | Fri, 25 Sep 2015 09:25:33 +0200 | From | Ingo Molnar <> | Subject | Re: rwx mapping between ex_table and rodata |
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* Kees Cook <keescook@chromium.org> wrote:
> On Thu, Sep 24, 2015 at 1:26 PM, Stephen Smalley <sds@tycho.nsa.gov> wrote: > > Hi, > > > > With the attached config and 4.3-rc2 on x86_64, I see the following in /sys/kernel/debug/kernel_page_tables: > > ... > > ---[ High Kernel Mapping ]--- > > 0xffffffff80000000-0xffffffff81000000 16M pmd > > 0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd > > 0xffffffff81600000-0xffffffff81775000 1492K ro GLB x pte > > 0xffffffff81775000-0xffffffff81800000 556K RW GLB x pte > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Btw., I think we should run this lookup automatically in late bootup, if CONFIG_X86_PTDUMP=y, and print a WARN()ing if there's any RWX permissions in the mappings.
That makes sure automated testing picks new bugs up.
Thanks,
Ingo
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