net: geneve: modify IP header check in geneve6_xmit_skb and geneve_xmit_skb

BugLink: https://bugs.launchpad.net/bugs/1929455
[ Upstream commit d13f048dd40e8577260cd43faea8ec9b77520197 ]

Modify the header size check in geneve6_xmit_skb and geneve_xmit_skb
to use pskb_inet_may_pull rather than pskb_network_may_pull. This fixes
two kernel selftest failures introduced by the commit introducing the
checks:
IPv4 over geneve6: PMTU exceptions
IPv4 over geneve6: PMTU exceptions - nexthop objects

It does this by correctly accounting for the fact that IPv4 packets may
transit over geneve IPv6 tunnels (and vice versa), and still fixes the
uninit-value bug fixed by the original commit.

Reported-by: kernel test robot <oliver.sang@intel.com>
Fixes: 6628ddfec758 ("net: geneve: check skb is large enough for IPv4/IPv6 header")
Suggested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 040edc6fc5609f5e37e6332ad625ec3932ca9089..0d8eb4a1dc2f33691a84834413e76b20c343f783 100644 (file)
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -891,7 +891,7 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
        __be16 sport;
        int err;
 
-       if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
+       if (!pskb_inet_may_pull(skb))
                return -EINVAL;
 
        sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
@@ -988,7 +988,7 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
        __be16 sport;
        int err;
 
-       if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
+       if (!pskb_inet_may_pull(skb))
                return -EINVAL;
 
        sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);