diff mbox

[net-next,5/5] net_sched: better precise estimation on packet length for untrusted packets

Message ID 1364278799-37285-6-git-send-email-jasowang@redhat.com
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Jason Wang March 26, 2013, 6:19 a.m. UTC 
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>
---
 net/core/dev.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)
diff mbox

Patch

diff --git a/net/core/dev.c b/net/core/dev.c
index de930b7..f5ad23b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -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;
 	}
 }