Re: Meltdown-US / Meltdown 3a Remaining Leakage

[Michael Schwarz <michael.schwarz () cispa de>]

Hi Alexander,

On 07.10.23 00:18, Solar Designer wrote:
> In Linux, /proc/interrupts is generally world-readable.  So perhaps
> that's something to fix first, since yes it's known to allow for
> keystroke timing attacks.  Should be fixed in the kernel or/and chmod'ed
> by the userland.  And then:
Yes, that is true. Android, for example, prevents unprivileged access 
since version 8 to this file to prevent such attacks:

https://issuetracker.google.com/issues/37140047?pli=1

If our proposed mitigation is implemented (e.g., as opt-in using a 
kernel command-line parameter), the implementation could additionally 
prevent unprivileged access to /proc/interrupts.

Michael

--

Dr. Michael Schwarz
Faculty

CISPA Helmholtz Center for Information Security
Stuhlsatzenhaus 5, Saarland Informatics Campus
66123 Saarbrücken, Germany
Mail: michael.schwarz () cispa de
Web: https://www.cispa.saarland