Re: [PATCH net] tuntap: fix use after free during release

From: David Miller
Date: Wed May 16 2018 - 14:20:59 EST


From: Jason Wang <jasowang@xxxxxxxxxx>
Date: Wed, 16 May 2018 20:39:33 +0800

> After commit b196d88aba8a ("tun: fix use after free for ptr_ring") we
> need clean up tx ring during release(). But unfortunately, it tries to
> do the cleanup blindly after socket were destroyed which will lead
> another use-after-free. Fix this by doing the cleanup before dropping
> the last reference of the socket in __tun_detach().
>
> Reported-by: Andrei Vagin <avagin@xxxxxxxxxxxxx>
> Acked-by: Andrei Vagin <avagin@xxxxxxxxxxxxx>
> Fixes: b196d88aba8a ("tun: fix use after free for ptr_ring")
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>

Applied and queued up for -stable.