Florian Westphal says:
====================
netfilter: bug fixes for net
1. Fix IP address check in irc DCC conntrack helper, this should check
the opposite direction rather than the destination address of the
packets' direction, from David Leadbeater.
2. bridge netfilter needs to drop dst references, from Harsh Modi.
This was fine back in the day the code was originally written,
but nowadays various tunnels can pre-set metadata dsts on packets.
3. Remove nf_conntrack_helper sysctl and the modparam toggle, users
need to explicitily assign the helpers to use via nftables or
iptables. Conntrack helpers, by design, may be used to add dynamic
port redirections to internal machines, so its necessary to restrict
which hosts/peers are allowed to use them.
It was discovered that improper checking in the irc DCC helper makes
it possible to trigger the 'please do dynamic port forward'
from outside by embedding a 'DCC' in a PING request; if the client
echos that back a expectation/port forward gets added.
The auto-assign-for-everything mechanism has been in "please don't do this"
territory since 2012. From Pablo.
4. Fix a memory leak in the netdev hook error unwind path, also from Pablo.
* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nf_conntrack_irc: Fix forged IP logic
netfilter: nf_tables: clean up hook list when offload flags check fails
netfilter: br_netfilter: Drop dst references before setting.
netfilter: remove nf_conntrack_helper sysctl and modparam toggles
====================
Link: https://lore.kernel.org/r/20220901071238.3044-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>