Jakub Kicinski 5f64c4c550 ipv6: weaken the v4mapped source check ... [ Upstream commit dcc32f4f183ab8479041b23a1525d48233df1d43 ] This reverts commit 6af1799aaf. Commit 6af1799aaf ("ipv6: drop incoming packets having a v4mapped source address") introduced an input check against v4mapped addresses. Use of such addresses on the wire is indeed questionable and not allowed on public Internet. As the commit pointed out https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02 lists potential issues. Unfortunately there are applications which use v4mapped addresses, and breaking them is a clear regression. For example v4mapped addresses (or any semi-valid addresses, really) may be used for uni-direction event streams or packet export. Since the issue which sparked the addition of the check was with TCP and request_socks in particular push the check down to TCPv6 and DCCP. This restores the ability to receive UDPv6 packets with v4mapped address as the source. Keep using the IPSTATS_MIB_INHDRERRORS statistic to minimize the user-visible changes. Fixes: 6af1799aaf ("ipv6: drop incoming packets having a v4mapped source address") Reported-by: Sunyi Shao <sunyishao@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-03-30 14:32:01 +02:00
..
crypto_test.c
crypto.c
ctrl.c
diag.c
Kconfig	mptcp: depends on IPV6 but not as a module	2020-10-21 08:05:40 -07:00
Makefile
mib.c	mptcp: print new line in mptcp_seq_show() if mptcp isn't in use	2020-12-07 17:45:29 -08:00
mib.h
mptcp_diag.c
options.c	mptcp: move mptcp_options_received's port initialization	2020-10-20 16:32:36 -07:00
pm_netlink.c	mptcp: Constify mptcp_pm_ops	2020-10-04 21:13:36 -07:00
pm.c
protocol.c	mptcp: skip to next candidate if subflow has unacked data	2021-02-23 15:53:23 +01:00
protocol.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-10-15 12:43:21 -07:00
subflow.c	ipv6: weaken the v4mapped source check	2021-03-30 14:32:01 +02:00
syncookies.c
token_test.c
token.c	mptcp: token: fix unititialized variable	2020-11-03 13:08:30 -08:00