On 9/22/06, Arnaldo Carvalho de Melo <arnaldo.melo@xxxxxxxxx> wrote:
On 9/22/06, Gerrit Renker <gerrit@xxxxxxxxxxxxxx> wrote: > Hi Arnaldo > | Gerrit, could you please use my net-2.6.19? > Of course - I didn't know it was active. I have just pulled your tree and > the patch applies without problem. OK, going over it now.
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 272e858..9e6344f 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -40,12 +40,17 @@ extern void dccp_tw_deschedule(struct in extern void dccp_time_wait(struct sock *sk, int state, int timeo); -/* FIXME: Right size this */ -#define DCCP_MAX_OPT_LEN 128 - -#define DCCP_MAX_PACKET_HDR 32 - -#define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER) +/* + * Set safe upper bounds for header and option length. Since Data Offset is 8 + * bits (RFC 4340, sec. 5.1), the total header length can never be more than + * 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1): + * - DCCP-Response with ACK Subheader and 4 bytes of Service code OR + * - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields + * Hence a safe upper bound for the maximum option length is 1020-28 = 992 + */ +#define DCCP_MAX_OPT_LEN 992 +#define DCCP_MAX_PACKET_HDR 28 +#define MAX_DCCP_HEADER (1020 + MAX_HEADER)
With this change DCCP_MAX_PACKET_HDR is not used anywhere, I'm rewriting it so that we use it to calculate MAX_DCCP_HEADER, something like: #define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int)) #define DCCP_MAX_PACKET_HDR 28 #define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR) #define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER) Thanks, - Arnaldo - To unsubscribe from this list: send the line "unsubscribe dccp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
