From de843723f9b989178762196fb24dd050cbe20ca3 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Wed, 25 Jun 2014 12:51:01 -0700 Subject: [PATCH] net: fix setting csum_start in skb_segment() Dave Jones reported that a crash is occurring in csum_partial tcp_gso_segment inet_gso_segment ? update_dl_migration skb_mac_gso_segment __skb_gso_segment dev_hard_start_xmit sch_direct_xmit __dev_queue_xmit ? dev_hard_start_xmit dev_queue_xmit ip_finish_output ? ip_output ip_output ip_forward_finish ip_forward ip_rcv_finish ip_rcv __netif_receive_skb_core ? __netif_receive_skb_core ? trace_hardirqs_on __netif_receive_skb netif_receive_skb_internal napi_gro_complete ? napi_gro_complete dev_gro_receive ? dev_gro_receive napi_gro_receive It looks like a likely culprit is that SKB_GSO_CB()->csum_start is not set correctly when doing non-scatter gather. We are using offset as opposed to doffset. Reported-by: Dave Jones Tested-by: Dave Jones Signed-off-by: Tom Herbert Signed-off-by: Eric Dumazet Fixes: 7e2b10c1e52ca ("net: Support for multiple checksums with gso") Acked-by: Tom Herbert 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 9cd5344fad73..c1a33033cbe2 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2993,7 +2993,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, skb_put(nskb, len), len, 0); SKB_GSO_CB(nskb)->csum_start = - skb_headroom(nskb) + offset; + skb_headroom(nskb) + doffset; continue; } -- 2.20.1