[PATCH 1/4] gsm0480: RELEASE COMPLETE can be without any payload

[Holger Freyther]

> On 22 Apr 2016, at 14:41, Sergey Kostanbaev <sergey.kostanbaev at gmail.com> wrote:
> 
> From: Sergey Kostanbaev <Sergey.Kostanbaev at gmail.com>
> 
> ---
> src/gsm/gsm0480.c | 6 ------
> 1 file changed, 6 deletions(-)
> 
> diff --git a/src/gsm/gsm0480.c b/src/gsm/gsm0480.c
> index 8963b78..55bddd5 100644
> --- a/src/gsm/gsm0480.c
> +++ b/src/gsm/gsm0480.c
> @@ -248,12 +248,6 @@ int gsm0480_decode_ss_request(const struct gsm48_hdr *hdr, uint16_t len,
> 				struct ss_request *req)
> {
> 	int rc = 0;
> -
> -	if (len < sizeof(*hdr) + 2) {
> -		LOGP(0, LOGL_DEBUG, "SS Request is too short.\n");
> -		return 0;
> -	}
> -
> 	if (gsm48_hdr_pdisc(hdr) == GSM48_PDISC_NC_SS) {
> 		req->transaction_id = hdr->proto_discr & 0x70;
> 		rc = parse_ss(hdr, len, req);

static int parse_ss_info_elements(const uint8_t *ss_ie, uint16_t len,
                                  struct ss_request *req)
{
        int rc = -1;
        /* Information Element Identifier - table 3.2 & GSM 04.08 section 10.5 */
        uint8_t iei;
        uint8_t iei_length;

        iei = ss_ie[0];
        iei_length = ss_ie[1];

        /* If the data does not fit, report an error */
        if (len - 2 < iei_length)
                return 0;

so this code works with uint16_t and assumes there is at least two bytes after the header. I don't know best practices for integer underflow/overflow (shall we use ssize_t)?

First we need a testcase
Second we need to remove the assumptions about at least two bytes in payload.

holger