netfilter: ipset: Limit the maximal range of consecutive elements to add/delete

netfilter: ipset: Limit the maximal range of consecutive elements to add/delete

BugLink: https://bugs.launchpad.net/bugs/1944610
[ Upstream commit 5f7b51bf09baca8e4f80cbe879536842bafb5f31 ]

The range size of consecutive elements were not limited. Thus one could
define a huge range which may result soft lockup errors due to the long
execution time. Now the range size is limited to 2^20 entries.

Reported-by: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>