It also wastes about half the allocated space because of kmalloc()
power-of-two roundups and struct recent_table layout.
Use vmalloc() instead to save space and be less prone to allocation
errors when memory is fragmented.
Reported-by: Miroslav Kratochvil <exa.exa@gmail.com> Reported-by: Dave Jones <davej@redhat.com> Reported-by: Harald Reindl <h.reindl@thelounge.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>