From cb73ee40b1b381eaf3749e6dbeed567bb38e5258 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 18 Jan 2019 12:05:39 +0100 Subject: [PATCH] net: ip_gre: use erspan key field for tunnel lookup Use ERSPAN key header field as tunnel key in gre_parse_header routine since ERSPAN protocol sets the key field of the external GRE header to 0 resulting in a tunnel lookup fail in ip6gre_err. In addition remove key field parsing and pskb_may_pull check in erspan_rcv and ip6erspan_rcv Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support") Signed-off-by: Lorenzo Bianconi Signed-off-by: David S. Miller --- net/ipv4/gre_demux.c | 17 +++++++++++++++++ net/ipv4/ip_gre.c | 9 --------- net/ipv6/ip6_gre.c | 4 ---- 3 files changed, 17 insertions(+), 13 deletions(-) diff --git a/net/ipv4/gre_demux.c b/net/ipv4/gre_demux.c index a4bf22ee3aed..7c4a41dc04bb 100644 --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -119,6 +120,22 @@ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, hdr_len += 4; } tpi->hdr_len = hdr_len; + + /* ERSPAN ver 1 and 2 protocol sets GRE key field + * to 0 and sets the configured key in the + * inner erspan header field + */ + if (greh->protocol == htons(ETH_P_ERSPAN) || + greh->protocol == htons(ETH_P_ERSPAN2)) { + struct erspan_base_hdr *ershdr; + + if (!pskb_may_pull(skb, nhs + hdr_len + sizeof(*ershdr))) + return -EINVAL; + + ershdr = (struct erspan_base_hdr *)options; + tpi->key = cpu_to_be32(get_session_id(ershdr)); + } + return hdr_len; } EXPORT_SYMBOL(gre_parse_header); diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index b1a74d80d868..20a64fe6254b 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -268,20 +268,11 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, int len; itn = net_generic(net, erspan_net_id); - len = gre_hdr_len + sizeof(*ershdr); - - /* Check based hdr len */ - if (unlikely(!pskb_may_pull(skb, len))) - return PACKET_REJECT; iph = ip_hdr(skb); ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); ver = ershdr->ver; - /* The original GRE header does not have key field, - * Use ERSPAN 10-bit session ID as key. - */ - tpi->key = cpu_to_be32(get_session_id(ershdr)); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags | TUNNEL_KEY, iph->saddr, iph->daddr, tpi->key); diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index b1be67ca6768..4416368dbd49 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -534,13 +534,9 @@ static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len, struct ip6_tnl *tunnel; u8 ver; - if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr)))) - return PACKET_REJECT; - ipv6h = ipv6_hdr(skb); ershdr = (struct erspan_base_hdr *)skb->data; ver = ershdr->ver; - tpi->key = cpu_to_be32(get_session_id(ershdr)); tunnel = ip6gre_tunnel_lookup(skb->dev, &ipv6h->saddr, &ipv6h->daddr, tpi->key, -- 2.34.1