diff options
author | Jason A. Donenfeld <Jason@zx2c4.com> | 2020-10-28 21:11:21 +0100 |
---|---|---|
committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2020-10-29 13:21:14 +0100 |
commit | 99e954f4871d9a760451c5ada99dfaae5df256e5 (patch) | |
tree | 5ff5c5a3ef63fa8fe7584f0e3228682a4e8c68f3 | |
parent | 25320ac50e6ddd8b935282f22dfddb579d528429 (diff) |
netns: check that route_me_harder packets use the right sk
If netfilter changes the packet mark, the packet is rerouted. The
ip_route_me_harder family of functions fails to use the right sk, opting
to instead use skb->sk, resulting in a routing loop when used with
tunnels. Fixing this inside of the compat layer with skb_orphan would
work but would cause other problems, by disabling TSQ, so instead we
warn if the calling kernel hasn't yet backported the fix for this.
Reported-by: Chen Minqiang <ptpt52@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
-rwxr-xr-x | src/tests/netns.sh | 9 | ||||
-rw-r--r-- | src/tests/qemu/kernel.config | 2 |
2 files changed, 11 insertions, 0 deletions
diff --git a/src/tests/netns.sh b/src/tests/netns.sh index c83ddc7..ecfe914 100755 --- a/src/tests/netns.sh +++ b/src/tests/netns.sh @@ -30,6 +30,7 @@ netns0="wg-test-$$-0" netns1="wg-test-$$-1" netns2="wg-test-$$-2" pretty() { echo -e "\x1b[32m\x1b[1m[+] ${1:+NS$1: }${2}\x1b[0m" >&3; } +compatwarn() { echo -e "\x1b[31m\x1b[1m[-] Tolerated failure: $1\x1b[0m" >&3; } pp() { pretty "" "$*"; "$@"; } maybe_exec() { if [[ $BASHPID -eq $$ ]]; then "$@"; else exec "$@"; fi; } n0() { pretty 0 "$*"; maybe_exec ip netns exec $netns0 "$@"; } @@ -316,6 +317,14 @@ pp sleep 3 n2 ping -W 1 -c 1 192.168.241.1 n1 wg set wg0 peer "$pub2" persistent-keepalive 0 +# Test that sk_bound_dev_if works +n1 ping -I wg0 -c 1 -W 1 192.168.241.2 +# What about when the mark changes and the packet must be rerouted? +n1 iptables -t mangle -I OUTPUT -j MARK --set-xmark 1 +n1 ping -c 1 -W 1 192.168.241.2 # First the boring case +n1 ping -I wg0 -c 1 -W 1 192.168.241.2 || compatwarn "sk_bound_dev_if test failed, but fix not backportable in compat layer" # Then the sk_bound_dev_if case +n1 iptables -t mangle -D OUTPUT -j MARK --set-xmark 1 + # Test that onion routing works, even when it loops n1 wg set wg0 peer "$pub3" allowed-ips 192.168.242.2/32 endpoint 192.168.241.2:5 ip1 addr add 192.168.242.1/24 dev wg0 diff --git a/src/tests/qemu/kernel.config b/src/tests/qemu/kernel.config index 071a43f..35e9a1b 100644 --- a/src/tests/qemu/kernel.config +++ b/src/tests/qemu/kernel.config @@ -17,10 +17,12 @@ CONFIG_NF_NAT=y CONFIG_NETFILTER_XTABLES=y CONFIG_NETFILTER_XT_NAT=y CONFIG_NETFILTER_XT_MATCH_LENGTH=y +CONFIG_NETFILTER_XT_MARK=y CONFIG_NF_CONNTRACK_IPV4=y CONFIG_NF_NAT_IPV4=y CONFIG_IP_NF_IPTABLES=y CONFIG_IP_NF_FILTER=y +CONFIG_IP_NF_MANGLE=y CONFIG_IP_NF_NAT=y CONFIG_IP_ADVANCED_ROUTER=y CONFIG_IP_MULTIPLE_TABLES=y |