Re: [PATCH] fix quadratic behavior of shrink_dcache_parent()

Russ Cox
2007-02-10T00:23:33Z

> "The file system mounted on /tmp/z in the example contains 2^50
> directories". heh.
>
> I do wonder how realistic this problem is in real life.

That's a fair concern, although I was trying this as part
of evaluating how much someone could hose a system
if we let them mount arbitrary FUSE servers. And the
answer is: they could make it completely unusable,
requiring reboot.

I ran a later test that printed how deep it got into
the file tree and it was only a few hundred thousand
if I recall correctly. A determined attacker might even
manage to do this in a normal file system.

But sure, it's not a common case. ;-)

Russ