Re: [PATCH net v4] sctp: asconf's process should verify address parameter is in the beginning

[Vlad Yasevich <vyasevic@redhat.com>]

On 08/26/2015 05:03 PM, Xin Long wrote:
> in sctp_process_asconf(), we get address parameter from the beginning of
> the addip params. but we never check if it's really there. if the addr
> param is not there, it still can pass sctp_verify_asconf(), then to be
> handled by sctp_process_asconf(), it will not be safe.
> 
> so add detection in sctp_verify_asconf() to check the address parameter is in
> the beginning, or return false to send abort.
> 
> Signed-off-by: Xin Long <lucien.xin@gmail.com>
> Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>

Acked-by: Vlad Yasevich <vyasevich@gmail.com>

-vlad

> ---
>  net/sctp/sm_make_chunk.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
> index 06320c8..f3fc881 100644
> --- a/net/sctp/sm_make_chunk.c
> +++ b/net/sctp/sm_make_chunk.c
> @@ -3132,12 +3132,14 @@ bool sctp_verify_asconf(const struct sctp_association *asoc,
>  		case SCTP_PARAM_IPV4_ADDRESS:
>  			if (length != sizeof(sctp_ipv4addr_param_t))
>  				return false;
> -			addr_param_seen = true;
> +			if (param.v == addip->addip_hdr.params)
> +				addr_param_seen = true;
>  			break;
>  		case SCTP_PARAM_IPV6_ADDRESS:
>  			if (length != sizeof(sctp_ipv6addr_param_t))
>  				return false;
> -			addr_param_seen = true;
> +			if (param.v == addip->addip_hdr.params)
> +				addr_param_seen = true;
>  			break;
>  		case SCTP_PARAM_ADD_IP:
>  		case SCTP_PARAM_DEL_IP:
>