Re: Users locking memory using futexes

From: Rusty Russell (
Date: Tue Nov 12 2002 - 12:17:47 EST

In message <> you write:
> Perez-Gonzalez, Inaky wrote:
> > [...] each time you lock a futex you are pinning the containing page
> > into physical memory, that would cause that if you have, for
> > example, 4000 futexes locked in 4000 different pages, there is going
> > to be 4 MB of memory locked in [...]
> Ouch! It looks to me like userspace can use FUTEX_FD to lock many
> pages of memory, achieving the same as mlock() but without the
> resource checks.
> Denial of service attack?

See "pipe".


  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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This archive was generated by hypermail 2b29 : Fri Nov 15 2002 - 22:00:26 EST