Messages in this thread | | | From | (Matthias Urlichs) | Subject | Re: x86 MSRs - example program | Date | 2 Mar 1997 01:33:59 +0100 |
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In linux.dev.kernel, article <m0w0aqh-000A8LC@cerebro>, mlehmann@hildesheim.sgh-net.de (Marc Lehmann) writes: > > ON the other hand... security hole????? how???????? > Cryptography. If you know exactly how long a given algorithm takes for different inputs, you can sometimes infer clues about the secret key.
It's highly unlikely that anybody ever tries to do that kind of thing to exploit security weaknesses on a Linux box, but you never know...
IMHO, we should have a bit in the securelevel variable which controls userspace read access to the cycle counter. Assuming that the securelevel variable ever becomes a bitmap. ;-)
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