Subject: Re: [PATCH net-next] net: tcp: dctcp_update_alpha() fixes.

From: Daniel Borkmann <[email-masked]>
Date: Thu, 11 Jun 2015 23:07:32 +0200

On 06/11/2015 07:11 AM, Eric Dumazet wrote:
> From: Eric Dumazet <[email-masked]>
>
> dctcp_alpha can be read by from dctcp_get_info() without
> synchro, so use WRITE_ONCE() to prevent compiler from using
> dctcp_alpha as a temporary variable.
>
> Also, playing with small dctcp_shift_g (like 1), can expose
> an overflow with 32bit values shifted 9 times before divide.
>
> Use an u64 field to avoid this problem, and perform the divide
> only if acked_bytes_ecn is not zero.
>
> Signed-off-by: Eric Dumazet <[email-masked]>

Change looks correct to me, thanks Eric!

Acked-by: Daniel Borkmann <[email-masked]>