nullfs and named pipes.
Robert Watson
rwatson at FreeBSD.org
Mon Feb 19 14:08:36 UTC 2007
On Mon, 19 Feb 2007, Robert Watson wrote:
> On Sun, 18 Feb 2007, Josef Karthauser wrote:
>
> Well, the worry would be that you would be replacing a clean error on
> failure with an occasional panic, the normal symptom of a race condition.
>
> I think I'm alright with the VFIFO case above, but I'm quite uncomfortable
> with the VSOCK case. In particular, I suspect that if the socket is closed,
> v_un will be reset in the lower layer, but continue to be a stale pointer in
> the upper layer, leading to accessing free'd or re-allocated kernel memory
> resulting in much badness. I've noticed tested this, but you might give it
> a try and see what happens.
Bad typing day. Should read "not tested this". In any case, you get the
idea: the problem here is a potential coherency issue on contents of v_un
between the two file system layers.
Robert N M Watson
Computer Laboratory
University of Cambridge
More information about the freebsd-fs
mailing list