[PATCH net v2] vxlan: fix too large pskb_may_pull with remote checksum

[Jiri Benc]

vxlan_remcsum is called after iptunnel_pull_header and thus the skb has
vxlan header already pulled. Don't include vxlan header again in the
calculation.

Signed-off-by: Jiri Benc <jb...@redhat.com>
---
v2: Changed wording of the patch description to explain where the header is
    pulled.
---
 drivers/net/vxlan.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 7bfcb9a62a5d..1c0fa364323e 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1143,7 +1143,7 @@ static int vxlan_igmp_leave(struct vxlan_dev *vxlan)
 static bool vxlan_remcsum(struct vxlanhdr *unparsed,
                          struct sk_buff *skb, u32 vxflags)
 {
-       size_t start, offset, plen;
+       size_t start, offset;
 
        if (!(unparsed->vx_flags & VXLAN_HF_RCO) || skb->remcsum_offload)
                goto out;
@@ -1151,9 +1151,7 @@ static bool vxlan_remcsum(struct vxlanhdr *unparsed,
        start = vxlan_rco_start(unparsed->vx_vni);
        offset = start + vxlan_rco_offset(unparsed->vx_vni);
 
-       plen = sizeof(struct vxlanhdr) + offset + sizeof(u16);
-
-       if (!pskb_may_pull(skb, plen))
+       if (!pskb_may_pull(skb, offset + sizeof(u16)))
                return false;
 
        skb_remcsum_process(skb, (void *)(vxlan_hdr(skb) + 1), start, offset,
-- 
1.8.3.1