From: Zheng Li Date: Wed, 28 Dec 2016 15:23:46 +0000 (+0800) Subject: ipv6: Should use consistent conditional judgement for ip6 fragment between __ip6_appe... X-Git-Tag: archive/raspbian/4.9.51-1+rpi1~8^2^2~47 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=58b2f0de631ba57145c9404a8b6510e88f31b1b8;p=linux-4.9.git ipv6: Should use consistent conditional judgement for ip6 fragment between __ip6_append_data and ip6_finish_output There is an inconsistent conditional judgement between __ip6_append_data and ip6_finish_output functions, the variable length in __ip6_append_data just include the length of application's payload and udp6 header, don't include the length of ipv6 header, but in ip6_finish_output use (skb->len > ip6_skb_dst_mtu(skb)) as judgement, and skb->len include the length of ipv6 header. That causes some particular application's udp6 payloads whose length are between (MTU - IPv6 Header) and MTU were fragmented by ip6_fragment even though the rst->dev support UFO feature. Add the length of ipv6 header to length in __ip6_append_data to keep consistent conditional judgement as ip6_finish_output for ip6 fragment. Signed-off-by: Zheng Li Signed-off-by: David S. Miller Gbp-Pq: Topic bugfix/all Gbp-Pq: Name ipv6-should-use-consistent-conditional-judgement-for.patch --- diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 1ac3cea49171..094e91123cbf 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1371,7 +1371,7 @@ emsgsize: */ cork->length += length; - if (((length > mtu) || + if ((((length + fragheaderlen) > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len &&