On Mon, Sep 25, 2017 at 01:19:26PM +0300, Dan Carpenter wrote:
> The sctp_for_each_transport() function takes an pointer to int. The
> cb->args[] array holds longs so it's only using the high 32 bits. It
> works on little endian system but will break on big endian 64 bit
> machines.
>
> Fixes: d25adbeb0cdb ("sctp: fix an use-after-free issue in sctp_sock_dump")
> Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
> ---
> v2: The v1 patch changed the function to take a long pointer, but v2
> just changes the caller.
>
> diff --git a/net/sctp/sctp_diag.c b/net/sctp/sctp_diag.c
> index 22ed01a76b19..a72a7d925d46 100644
> --- a/net/sctp/sctp_diag.c
> +++ b/net/sctp/sctp_diag.c
> @@ -463,6 +463,7 @@ static void sctp_diag_dump(struct sk_buff *skb, struct
> netlink_callback *cb,
> .r = r,
> .net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN),
> };
> + int pos = cb->args[2];
>
> /* eps hashtable dumps
> * args:
> @@ -493,7 +494,8 @@ static void sctp_diag_dump(struct sk_buff *skb, struct
> netlink_callback *cb,
> goto done;
>
> sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump,
> - net, (int *)&cb->args[2], &commp);
> + net, &pos, &commp);
> + cb->args[2] = pos;
>
> done:
> cb->args[1] = cb->args[4];
>
Acked-by: Neil Horman <nhor...@tuxdriver.com>