net_sched: better precise estimation on packet length for untrusted packets

gso_segs were reset to zero when kernel receive packets from untrusted
source. But we use this zero value to estimate precise packet len which is
wrong. So this patch tries to estimate the correct gso_segs value before using
it in qdisc_pkt_len_init().

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jason Wang 2013-03-25 20:19:59 +00:00 committed by David S. Miller
parent f9ca8f7439
commit 15e5a03071

View File

@ -2588,6 +2588,7 @@ static void qdisc_pkt_len_init(struct sk_buff *skb)
*/
if (shinfo->gso_size) {
unsigned int hdr_len;
u16 gso_segs = shinfo->gso_segs;
/* mac layer + network layer */
hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
@ -2597,7 +2598,12 @@ static void qdisc_pkt_len_init(struct sk_buff *skb)
hdr_len += tcp_hdrlen(skb);
else
hdr_len += sizeof(struct udphdr);
qdisc_skb_cb(skb)->pkt_len += (shinfo->gso_segs - 1) * hdr_len;
if (shinfo->gso_type & SKB_GSO_DODGY)
gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
shinfo->gso_size);
qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
}
}