Re: fuse, get_user_pages, flush_anon_page, aliasing caches and allthat again

From: Jan Engelhardt
Date: Thu Dec 21 2006 - 16:06:55 EST



On Dec 21 2006 18:51, Miklos Szeredi wrote:
>
>The root of the problem is that copy_to_user() may cause page faults
>on the userspace buffer, and the page fault might (in case of a
>maliciously crafted filesystem) recurse into the filesystem itself.

Would it be worthwhile to mlock the page? I know that needs root
privs or some capability, but a static buffer could be put aside when
fusermount is run.


-`J'
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