From: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> [ Upstream commit 0ab03f353d3613ea49d1f924faf98559003670a8 ] Currently we may merge incorrectly a received GSO packet or a packet with frag_list into a packet sitting in the gro_hash list. skb_segment() may crash case because the assumptions on the skb layout are not met. The correct behaviour would be to flush the packet in the gro_hash list and send the received GSO packet directly afterwards. Commit d61d072e87c8e ("net-gro: avoid reorders") sets NAPI_GRO_CB(skb)->flush in this case, but this is not checked before merging. This patch makes sure to check this flag and to not merge in that case. Fixes: d61d072e87c8e ("net-gro: avoid reorders") Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/core/skbuff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3808,7 +3808,7 @@ int skb_gro_receive(struct sk_buff **hea struct sk_buff *lp, *p = *head; unsigned int delta_truesize; - if (unlikely(p->len + len >= 65536)) + if (unlikely(p->len + len >= 65536 || NAPI_GRO_CB(skb)->flush)) return -E2BIG; lp = NAPI_GRO_CB(p)->last;