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Date:   Sun, 28 Oct 2018 23:43:07 -0400 (EDT)
From:   Nicolas Pitre <nicolas.pitre@linaro.org>
To:     Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
cc:     linux-kernel@vger.kernel.org
Subject: Re: Cramfs: "unable to handle kernel paging request" when reading
 a file from a fuzzed FS image
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On Sun, 28 Oct 2018, Anatoly Trosinenko wrote:

> Hello,
> 
> When reading a file from a fuzzed cramfs image, unhandled kernel
> paging request occurs.

Hmmm... It doesn't show up on my test system.

> How to reproduce with kvm-xfstests:
> 1) Checkout the v4.19 tag, copy x86_64-config-4.14 to .config, perform
> `make olddefconfig`
> 2) Enable Cramfs in the config, then compile
> 3) In the `kvm-xfstests shell` perform:
> 
> root@kvm-xfstests:~# mount /vtmp
> root@kvm-xfstests:~# mount /vtmp/cramfs.img /mnt

How do I populate /vtmp? Mine is empty at this point. I imagine I should 
put the cramfs image somewhere on the host, but I'm not that familiar 
withkvm.


Nicolas