[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20120705124029.GA2795@neilslaptop.think-freely.org>
Date: Thu, 5 Jul 2012 08:40:30 -0400
From: Neil Horman <nhorman@...driver.com>
To: Gao feng <gaofeng@...fujitsu.com>
Cc: davem@...emloft.net, netdev@...r.kernel.org,
linux-kernel@...r.kernel.org, tj@...nel.org, lizefan@...wei.com,
eric.dumazet@...il.com
Subject: Re: [PATCH v2] cgroup: fix panic in netprio_cgroup
On Thu, Jul 05, 2012 at 05:28:40PM +0800, Gao feng wrote:
> we set max_prioidx to the first zero bit index of prioidx_map in
> function get_prioidx.
>
> So when we delete the low index netprio cgroup and adding a new
> netprio cgroup again,the max_prioidx will be set to the low index.
>
> when we set the high index cgroup's net_prio.ifpriomap,the function
> write_priomap will call update_netdev_tables to alloc memory which
> size is sizeof(struct netprio_map) + sizeof(u32) * (max_prioidx + 1),
> so the size of array that map->priomap point to is max_prioidx +1,
> which is low than what we actually need.
>
> fix this by adding check in get_prioidx,only set max_prioidx when
> max_prioidx low than the new prioidx.
>
> Signed-off-by: Gao feng <gaofeng@...fujitsu.com>
> ---
> net/core/netprio_cgroup.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
> index 5b8aa2f..aa907ed 100644
> --- a/net/core/netprio_cgroup.c
> +++ b/net/core/netprio_cgroup.c
> @@ -49,8 +49,9 @@ static int get_prioidx(u32 *prio)
> return -ENOSPC;
> }
> set_bit(prioidx, prioidx_map);
> + if (atomic_read(&max_prioidx) < prioidx)
> + atomic_set(&max_prioidx, prioidx);
> spin_unlock_irqrestore(&prioidx_map_lock, flags);
> - atomic_set(&max_prioidx, prioidx);
> *prio = prioidx;
> return 0;
> }
> --
> 1.7.7.6
>
>
Acked-by: Neil Horman <nhorman@...driver.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists