tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
xfrm6: Don't call icmpv6_send on local error
Calling icmpv6_send() on a local message size error leads to
an incorrect update of the path mtu. So use xfrm6_local_rxpmtu()
to notify about the pmtu if the IPV6_DONTFRAG socket option is
set on an udp or raw socket, according RFC 3542 and use
ipv6_local_error() otherwise.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
authored by
Steffen Klassert
and committed by
David S. Miller
dd767856
299b0767
+54
-2
+54
-2
net/ipv6/xfrm6_output.c
+54
-2
net/ipv6/xfrm6_output.c
···
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EXPORT_SYMBOL(xfrm6_find_1stfragopt);
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+
static int xfrm6_local_dontfrag(struct sk_buff *skb)
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{
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int proto;
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struct sock *sk = skb->sk;
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+
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if (sk) {
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proto = sk->sk_protocol;
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+
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if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
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return inet6_sk(sk)->dontfrag;
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}
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return 0;
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}
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+
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static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
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{
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struct flowi6 fl6;
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struct sock *sk = skb->sk;
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fl6.flowi6_oif = sk->sk_bound_dev_if;
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ipv6_addr_copy(&fl6.daddr, &ipv6_hdr(skb)->daddr);
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ipv6_local_rxpmtu(sk, &fl6, mtu);
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}
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+
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static void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
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{
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struct flowi6 fl6;
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struct sock *sk = skb->sk;
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fl6.fl6_dport = inet_sk(sk)->inet_dport;
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ipv6_addr_copy(&fl6.daddr, &ipv6_hdr(skb)->daddr);
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+
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ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
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}
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+
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static int xfrm6_tunnel_check_size(struct sk_buff *skb)
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{
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int mtu, ret = 0;
···
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if (!skb->local_df && skb->len > mtu) {
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skb->dev = dst->dev;
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-
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
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+
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if (xfrm6_local_dontfrag(skb))
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xfrm6_local_rxpmtu(skb, mtu);
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else if (skb->sk)
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xfrm6_local_error(skb, mtu);
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else
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icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
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ret = -EMSGSIZE;
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}
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···
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{
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struct dst_entry *dst = skb_dst(skb);
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struct xfrm_state *x = dst->xfrm;
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int mtu = ip6_skb_dst_mtu(skb);
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+
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if (skb->len > mtu && xfrm6_local_dontfrag(skb)) {
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xfrm6_local_rxpmtu(skb, mtu);
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return -EMSGSIZE;
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} else if (!skb->local_df && skb->len > mtu && skb->sk) {
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xfrm6_local_error(skb, mtu);
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return -EMSGSIZE;
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}
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if ((x && x->props.mode == XFRM_MODE_TUNNEL) &&
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-
((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
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+
((skb->len > mtu && !skb_is_gso(skb)) ||
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dst_allfrag(skb_dst(skb)))) {
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return ip6_fragment(skb, x->outer_mode->afinfo->output_finish);
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}