This is a note to let you know that I've just added the patch titled
ipv4: Fix incorrect route flushing when table ID 0 is used
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ipv4-fix-incorrect-route-flushing-when-table-id-0-is.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 26c24e7639ac31a2afa351e2a208b4e501469648
Author: Ido Schimmel <idosch@xxxxxxxxxx>
Date: Sun Dec 4 09:50:45 2022 +0200
ipv4: Fix incorrect route flushing when table ID 0 is used
[ 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@xxxxxxxxxx>
Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxx>
Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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
