From: Ido Schimmel idosch@nvidia.com
[ Upstream commit c0d999348e01df03e0a7f550351f3907fabbf611 ]
Cited commit added the table ID to the FIB info structure, but did not properly initialize it when table ID 0 is used. This can lead to a route in the default VRF with a preferred source address not being flushed when the address is deleted.
Consider the following example:
# ip address add dev dummy1 192.0.2.1/28 # ip address add dev dummy1 192.0.2.17/28 # ip route add 198.51.100.0/24 via 192.0.2.2 src 192.0.2.17 metric 100 # ip route add table 0 198.51.100.0/24 via 192.0.2.2 src 192.0.2.17 metric 200 # ip route show 198.51.100.0/24 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 100 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 200
Both routes are installed in the default VRF, but they are using two different FIB info structures. One with a metric of 100 and table ID of 254 (main) and one with a metric of 200 and table ID of 0. Therefore, when the preferred source address is deleted from the default VRF, the second route is not flushed:
# ip address del dev dummy1 192.0.2.17/28 # ip route show 198.51.100.0/24 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 200
Fix by storing a table ID of 254 instead of 0 in the route configuration structure.
Add a test case that fails before the fix:
# ./fib_tests.sh -t ipv4_del_addr
IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Table ID 0 TEST: Route removed in default VRF when source address deleted [FAIL]
Tests passed: 8 Tests failed: 1
And passes after:
# ./fib_tests.sh -t ipv4_del_addr
IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Table ID 0 TEST: Route removed in default VRF when source address deleted [ OK ]
Tests passed: 9 Tests failed: 0
Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Reported-by: Donald Sharp sharpd@nvidia.com Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: David Ahern dsahern@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/fib_frontend.c | 3 +++ tools/testing/selftests/net/fib_tests.sh | 10 ++++++++++ 2 files changed, 13 insertions(+)
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 943edf4ad4db..3528e8befa58 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -841,6 +841,9 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, return -EINVAL; }
+ if (!cfg->fc_table) + cfg->fc_table = RT_TABLE_MAIN; + return 0; errout: return err; diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh index 11c89148b19f..5637b5dadabd 100755 --- a/tools/testing/selftests/net/fib_tests.sh +++ b/tools/testing/selftests/net/fib_tests.sh @@ -1712,11 +1712,13 @@ ipv4_del_addr_test() $IP addr add dev dummy1 172.16.104.1/24 $IP addr add dev dummy1 172.16.104.11/24 $IP addr add dev dummy1 172.16.104.12/24 + $IP addr add dev dummy1 172.16.104.13/24 $IP addr add dev dummy2 172.16.104.1/24 $IP addr add dev dummy2 172.16.104.11/24 $IP addr add dev dummy2 172.16.104.12/24 $IP route add 172.16.105.0/24 via 172.16.104.2 src 172.16.104.11 $IP route add 172.16.106.0/24 dev lo src 172.16.104.12 + $IP route add table 0 172.16.107.0/24 via 172.16.104.2 src 172.16.104.13 $IP route add vrf red 172.16.105.0/24 via 172.16.104.2 src 172.16.104.11 $IP route add vrf red 172.16.106.0/24 dev lo src 172.16.104.12 set +e @@ -1762,6 +1764,14 @@ ipv4_del_addr_test() $IP ro ls vrf red | grep -q 172.16.106.0/24 log_test $? 0 "Route in VRF is not removed by address delete"
+ # removing address from device in default vrf should remove route from + # the default vrf even when route was inserted with a table ID of 0. + echo " Table ID 0" + + $IP addr del dev dummy1 172.16.104.13/24 + $IP ro ls | grep -q 172.16.107.0/24 + log_test $? 1 "Route removed in default VRF when source address deleted" + $IP li del dummy1 $IP li del dummy2 cleanup