We don't catch the case if an unsupported protocol is submitted
to the xfrm6 protocol handlers, this can lead to NULL pointer
dereferences. Fix this by adding the appropriate checks.
Fixes: 7e14ea15 ("xfrm6: Add IPsec protocol multiplexer")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This patch adds an IPsec protocol multiplexer for ipv6. With
this it is possible to add alternative protocol handlers, as
needed for IPsec virtual tunnel interfaces.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>