On Tue, Jun 17, 2014 at 06:58:05AM +0400, Konstantin Khlebnikov wrote:
> This fixes use-after-free of epi->fllink.next inside list loop macro.
> This loop actually releases elements in the body. List is rcu-protected
> but here we cannot hold rcu_read_lock because we need to lock mutex inside.
>
> Obvious solution is to use list_for_each_entry_safe(). RCU-ness isn't
> essential
> because nobody can change this list under us, it's final fput for this file.
>
> Bug is here since ae10b2b4eb01bedc91d29d5c5bb9e416fd806c40
> ("epoll: optimize EPOLL_CTL_DEL using rcu")
>
> Signed-off-by: Konstantin Khlebnikov <[email protected]>
> Reported-by: Cyrill Gorcunov <[email protected]>
> Cc: Stable <[email protected]> # 3.13+
> Cc: Sasha Levin <[email protected]>
> Cc: Jason Baron <[email protected]>
Acked-by: Cyrill Gorcunov <[email protected]>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
