In situations where an skb is paged, the transport header pointer and
tail pointer can be the same because the skb contents are in frags.
This results in ioctl(SIOCINQ/FIONREAD) incorrectly returning a
length of 0 when the length to receive is actually greater than zero.
skb->len is already correctly set in ip6_input_finish() with
pskb_pull(), so use skb->len as it always returns the correct result
for both linear and paged data.
Signed-off-by: Jamie Bainbridge <jbainbri@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
105f5528b9