From 64289c8e6851bca0e589e064c9a5c9fbd6ae5dd4 Mon Sep 17 00:00:00 2001 From: Jarek Poplawski Date: Sat, 4 Sep 2010 10:34:29 +0000 Subject: [PATCH] gro: Re-fix different skb headrooms The patch: "gro: fix different skb headrooms" in its part: "2) allocate a minimal skb for head of frag_list" is buggy. The copied skb has p->data set at the ip header at the moment, and skb_gro_offset is the length of ip + tcp headers. So, after the change the length of mac header is skipped. Later skb_set_mac_header() sets it into the NET_SKB_PAD area (if it's long enough) and ip header is misaligned at NET_SKB_PAD + NET_IP_ALIGN offset. There is no reason to assume the original skb was wrongly allocated, so let's copy it as it was. bugzilla : https://bugzilla.kernel.org/show_bug.cgi?id=16626 fixes commit: 3d3be4333fdf6faa080947b331a6a19bce1a4f57 Reported-by: Plamen Petrov Signed-off-by: Jarek Poplawski CC: Eric Dumazet Acked-by: Eric Dumazet Tested-by: Plamen Petrov Signed-off-by: David S. Miller --- net/core/skbuff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 26396ff67cf9..c83b421341c0 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2706,7 +2706,7 @@ int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) } else if (skb_gro_len(p) != pinfo->gso_size) return -E2BIG; - headroom = NET_SKB_PAD + NET_IP_ALIGN; + headroom = skb_headroom(p); nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); if (unlikely(!nskb)) return -ENOMEM; -- 2.20.1