From d16beab575e17e46a4b187fb9f8211fab3adfbae Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 3 Apr 2014 09:28:10 -0700 Subject: [PATCH] net-gro: reset skb->truesize in napi_reuse_skb() [ Upstream commit e33d0ba8047b049c9262fdb1fcafb93cb52ceceb ] Recycling skb always had been very tough... This time it appears GRO layer can accumulate skb->truesize adjustments made by drivers when they attach a fragment to skb. skb_gro_receive() can only subtract from skb->truesize the used part of a fragment. I spotted this problem seeing TcpExtPruneCalled and TcpExtTCPRcvCollapsed that were unexpected with a recent kernel, where TCP receive window should be sized properly to accept traffic coming from a driver not overshooting skb->truesize. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/dev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/core/dev.c b/net/core/dev.c index cebdc15..b47375d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3574,6 +3574,7 @@ static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) skb->vlan_tci = 0; skb->dev = napi->dev; skb->skb_iif = 0; + skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); napi->skb = skb; } -- 2.7.4