- case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */
- length--;
- continue;
- default:
- opsize=*ptr++;
- if (opsize < 2) /* "silly options" */
- return;
- if (opsize > length)
- return; /* don't parse partial options */
- switch (opcode) {
- case TCPOPT_MSS:
- if (opsize==TCPOLEN_MSS && th->syn && !estab) {
- u16 in_mss = ntohs(get_unaligned((__be16 *)ptr));
- if (in_mss) {
- if (opt_rx->user_mss && opt_rx->user_mss < in_mss)
- in_mss = opt_rx->user_mss;
- opt_rx->mss_clamp = in_mss;
- }
- }
- break;
- case TCPOPT_WINDOW:
- if (opsize==TCPOLEN_WINDOW && th->syn && !estab)
- if (sysctl_tcp_window_scaling) {
- __u8 snd_wscale = *(__u8 *) ptr;
- opt_rx->wscale_ok = 1;
- if (snd_wscale > 14) {
- if (net_ratelimit())
- printk(KERN_INFO "tcp_parse_options: Illegal window "
- "scaling value %d >14 received.\n",
- snd_wscale);
- snd_wscale = 14;
- }
- opt_rx->snd_wscale = snd_wscale;
- }
- break;
- case TCPOPT_TIMESTAMP:
- if (opsize==TCPOLEN_TIMESTAMP) {
- if ((estab && opt_rx->tstamp_ok) ||
- (!estab && sysctl_tcp_timestamps)) {
- opt_rx->saw_tstamp = 1;
- opt_rx->rcv_tsval = ntohl(get_unaligned((__be32 *)ptr));
- opt_rx->rcv_tsecr = ntohl(get_unaligned((__be32 *)(ptr+4)));
- }
+ if (opsize > length)
+ return; /* don't parse partial options */
+ switch (opcode) {
+ case TCPOPT_MSS:
+ if (opsize == TCPOLEN_MSS && th->syn && !estab) {
+ u16 in_mss = ntohs(get_unaligned((__be16 *)ptr));
+ if (in_mss) {
+ if (opt_rx->user_mss &&
+ opt_rx->user_mss < in_mss)
+ in_mss = opt_rx->user_mss;
+ opt_rx->mss_clamp = in_mss;