Re: [kernel-hardening] 2015 kernel CVEs

["Hanno Böck" <hanno@hboeck.de>]

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On Tue, 19 Jan 2016 14:28:12 +0300
Dan Carpenter <dan.carpenter@oracle.com> wrote:

> There was only a coupls CVEs that looks like they came from a
> filesystem fuzzer where you create a corrupt filesystems and then try
> use them.

I tried that, but it didn't lead to any results in the kernel [1].
What I did:
* Use filesystem checking tools (fsck) and fuzz them with afl
* Use the queue created by afl and try to mount these with a
  kasan-enabled kernel

My conclusion was that the filesystem code in the kernel is relatively
robust (at least robust enough for this trivial fuzzing).
But it led to a number of bugs discovered in filesystem fsck tools.

> There was only one that might have come from a USB fuzzer.
> We probably should be testing those things better.

This is surprising to me. There was a talk at black hat amsterdam in
2014 about a project trying to do exactly this. They sounded like they
have dozends of crashers that just need to be sorted and reported
upstream. Here's the code [2] and the talk [3].
Maybe this project has stalled and needs someone to look at it?

[1]
https://www.coreinfrastructure.org/sites/cii/files/pages/files/2015-09-fuzzing-report.pdf
[2] https://github.com/schumilo/vUSBf
[3] https://www.youtube.com/watch?v=OAbzN8k6Am4


-- 
Hanno Böck
http://hboeck.de/

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