rcu_bh is no longer a win, especially for objects freed
with standard call_rcu().
Switch neighbour code to no longer disable BH when not necessary.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We have many lockless accesses to n->nud_state.
Before adding another one in the following patch,
add annotations to readers and writers.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
if (!type)
continue;
if (type > RTAX_MAX)
return false;
...
fi_val = fi->fib_metrics->metrics[type - 1];
@type being used as an array index, we need to prevent
cpu speculation or risk leaking kernel memory content.
Fixes: 5f9ae3d9e7 ("ipv4: do metrics match when looking up and deleting a route")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230120133140.3624204-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cited commit added the table ID to the FIB info structure, but did not
prevent structures with different table IDs from being consolidated.
This can lead to routes being flushed from a VRF when an address is
deleted from a different VRF.
Fix by taking the table ID into account when looking for a matching FIB
info. This is already done for FIB info structures backed by a nexthop
object in fib_find_info_nh().
Add test cases that fail 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 [FAIL]
TEST: Route in default VRF not removed [ OK ]
RTNETLINK answers: File exists
TEST: Route removed in default VRF when source address deleted [ OK ]
TEST: Route in VRF is not removed by address delete [FAIL]
Tests passed: 6
Tests failed: 2
And pass 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 ]
Tests passed: 8
Tests failed: 0
Fixes: 5a56a0b3a4 ("net: Don't delete routes in different VRFs")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When the kernel receives a route deletion request from user space it
tries to delete a route that matches the route attributes specified in
the request.
If only prefix information is specified in the request, the kernel
should delete the first matching FIB alias regardless of its associated
FIB info. However, an error is currently returned when the FIB info is
backed by a nexthop object:
# ip nexthop add id 1 via 192.0.2.2 dev dummy10
# ip route add 198.51.100.0/24 nhid 1
# ip route del 198.51.100.0/24
RTNETLINK answers: No such process
Fix by matching on such a FIB info when legacy nexthop attributes are
not specified in the request. An earlier check already covers the case
where a nexthop ID is specified in the request.
Add tests that cover these flows. Before the fix:
# ./fib_nexthops.sh -t ipv4_fcnal
...
TEST: Delete route when not specifying nexthop attributes [FAIL]
Tests passed: 11
Tests failed: 1
After the fix:
# ./fib_nexthops.sh -t ipv4_fcnal
...
TEST: Delete route when not specifying nexthop attributes [ OK ]
Tests passed: 12
Tests failed: 0
No regressions in other tests:
# ./fib_nexthops.sh
...
Tests passed: 228
Tests failed: 0
# ./fib_tests.sh
...
Tests passed: 186
Tests failed: 0
Cc: stable@vger.kernel.org
Reported-by: Jonas Gorski <jonas.gorski@gmail.com>
Tested-by: Jonas Gorski <jonas.gorski@gmail.com>
Fixes: 493ced1ac4 ("ipv4: Allow routes to use nexthop objects")
Fixes: 6bf92d70e6 ("net: ipv4: fix route with nexthop object delete warning")
Fixes: 61b91eb33a ("ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20221124210932.2470010-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 747c143072.
As explained by Julian, nhc_scope is related to nhc_gw, not to the route.
Revert the original patch. The initial problem is fixed differently in the
next commit.
Link: https://lore.kernel.org/netdev/6c8a44ba-c2d5-cdf-c5c7-5baf97cba38@ssi.bg/
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Gwangun Jung reported a slab-out-of-bounds access in fib_nh_match:
fib_nh_match+0xf98/0x1130 linux-6.0-rc7/net/ipv4/fib_semantics.c:961
fib_table_delete+0x5f3/0xa40 linux-6.0-rc7/net/ipv4/fib_trie.c:1753
inet_rtm_delroute+0x2b3/0x380 linux-6.0-rc7/net/ipv4/fib_frontend.c:874
Separate nexthop objects are mutually exclusive with the legacy
multipath spec. Fix fib_nh_match to return if the config for the
to be deleted route contains a multipath spec while the fib_info
is using a nexthop object.
Fixes: 493ced1ac4 ("ipv4: Allow routes to use nexthop objects")
Fixes: 6bf92d70e6 ("net: ipv4: fix route with nexthop object delete warning")
Reported-by: Gwangun Jung <exsociety@gmail.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While reading sysctl_fib_multipath_use_neigh, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its reader.
Fixes: a6db4494d2 ("net: ipv4: Consider failed nexthops in multipath routes")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a nexthop is added, without a gw address, the default scope was set
to 'host'. Thus, when a source address is selected, 127.0.0.1 may be chosen
but rejected when the route is used.
When using a route without a nexthop id, the scope can be configured in the
route, thus the problem doesn't exist.
To explain more deeply: when a user creates a nexthop, it cannot specify
the scope. To create it, the function nh_create_ipv4() calls fib_check_nh()
with scope set to 0. fib_check_nh() calls fib_check_nh_nongw() wich was
setting scope to 'host'. Then, nh_create_ipv4() calls
fib_info_update_nhc_saddr() with scope set to 'host'. The src addr is
chosen before the route is inserted.
When a 'standard' route (ie without a reference to a nexthop) is added,
fib_create_info() calls fib_info_update_nhc_saddr() with the scope set by
the user. iproute2 set the scope to 'link' by default.
Here is a way to reproduce the problem:
ip netns add foo
ip -n foo link set lo up
ip netns add bar
ip -n bar link set lo up
sleep 1
ip -n foo link add name eth0 type dummy
ip -n foo link set eth0 up
ip -n foo address add 192.168.0.1/24 dev eth0
ip -n foo link add name veth0 type veth peer name veth1 netns bar
ip -n foo link set veth0 up
ip -n bar link set veth1 up
ip -n bar address add 192.168.1.1/32 dev veth1
ip -n bar route add default dev veth1
ip -n foo nexthop add id 1 dev veth0
ip -n foo route add 192.168.1.1 nhid 1
Try to get/use the route:
> $ ip -n foo route get 192.168.1.1
> RTNETLINK answers: Invalid argument
> $ ip netns exec foo ping -c1 192.168.1.1
> ping: connect: Invalid argument
Try without nexthop group (iproute2 sets scope to 'link' by dflt):
ip -n foo route del 192.168.1.1
ip -n foo route add 192.168.1.1 dev veth0
Try to get/use the route:
> $ ip -n foo route get 192.168.1.1
> 192.168.1.1 dev veth0 src 192.168.0.1 uid 0
> cache
> $ ip netns exec foo ping -c1 192.168.1.1
> PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
> 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=0.039 ms
>
> --- 192.168.1.1 ping statistics ---
> 1 packets transmitted, 1 received, 0% packet loss, time 0ms
> rtt min/avg/max/mdev = 0.039/0.039/0.039/0.000 ms
CC: stable@vger.kernel.org
Fixes: 597cfe4fc3 ("nexthop: Add support for IPv4 nexthops")
Reported-by: Edwin Brossette <edwin.brossette@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20220713114853.29406-1-nicolas.dichtel@6wind.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
While reading nexthop_compat_mode, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 4f80116d3d ("net: ipv4: add sysctl for nexthop api compatibility mode")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.
Rename:
dev_hold_track() -> netdev_hold()
dev_put_track() -> netdev_put()
dev_replace_track() -> netdev_ref_replace()
Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the new dscp_t type to replace the tos field of struct fib_rt_info.
This ensures ECN bits are ignored and makes it compatible with the
fa_dscp field of struct fib_alias.
This also allows sparse to flag potential incorrect uses of DSCP and
ECN bits.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The fundamental premise of VRF and l3mdev core code is binding a socket
to a device (l3mdev or netdev with an L3 domain) to indicate L3 scope.
Legacy code resets flowi_oif to the l3mdev losing any original port
device binding. Ben (among others) has demonstrated use cases where the
original port device binding is important and needs to be retained.
This patch handles that by adding a new entry to the common flow struct
that can indicate the l3mdev index for later rule and table matching
avoiding the need to reset flowi_oif.
In addition to allowing more use cases that require port device binds,
this patch brings a few datapath simplications:
1. l3mdev_fib_rule_match is only called when walking fib rules and
always after l3mdev_update_flow. That allows an optimization to bail
early for non-VRF type uses cases when flowi_l3mdev is not set. Also,
only that index needs to be checked for the FIB table id.
2. l3mdev_update_flow can be called with flowi_oif set to a l3mdev
(e.g., VRF) device. By resetting flowi_oif only for this case the
FLOWI_FLAG_SKIP_NH_OIF flag is not longer needed and can be removed,
removing several checks in the datapath. The flowi_iif path can be
simplified to only be called if the it is not loopback (loopback can
not be assigned to an L3 domain) and the l3mdev index is not already
set.
3. Avoid another device lookup in the output path when the fib lookup
returns a reject failure.
Note: 2 functional tests for local traffic with reject fib rules are
updated to reflect the new direct failure at FIB lookup time for ping
rather than the failure on packet path. The current code fails like this:
HINT: Fails since address on vrf device is out of device scope
COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1
ping: Warning: source address might be selected on device other than: eth1
PING 172.16.3.1 (172.16.3.1) from 172.16.3.1 eth1: 56(84) bytes of data.
--- 172.16.3.1 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms
where the test now directly fails:
HINT: Fails since address on vrf device is out of device scope
COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1
ping: connect: No route to host
Signed-off-by: David Ahern <dsahern@kernel.org>
Tested-by: Ben Greear <greearb@candelatech.com>
Link: https://lore.kernel.org/r/20220314204551.16369-1-dsahern@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
fib_alias_hw_flags_set() can be used by concurrent threads,
and is only RCU protected.
We need to annotate accesses to following fields of struct fib_alias:
offload, trap, offload_failed
Because of READ_ONCE()WRITE_ONCE() limitations, make these
field u8.
BUG: KCSAN: data-race in fib_alias_hw_flags_set / fib_alias_hw_flags_set
read to 0xffff888134224a6a of 1 bytes by task 2013 on cpu 1:
fib_alias_hw_flags_set+0x28a/0x470 net/ipv4/fib_trie.c:1050
nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline]
nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline]
nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline]
nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline]
nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline]
nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477
process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
process_scheduled_works kernel/workqueue.c:2370 [inline]
worker_thread+0x7df/0xa70 kernel/workqueue.c:2456
kthread+0x1bf/0x1e0 kernel/kthread.c:377
ret_from_fork+0x1f/0x30
write to 0xffff888134224a6a of 1 bytes by task 4872 on cpu 0:
fib_alias_hw_flags_set+0x2d5/0x470 net/ipv4/fib_trie.c:1054
nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline]
nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline]
nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline]
nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline]
nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline]
nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477
process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
process_scheduled_works kernel/workqueue.c:2370 [inline]
worker_thread+0x7df/0xa70 kernel/workqueue.c:2456
kthread+0x1bf/0x1e0 kernel/kthread.c:377
ret_from_fork+0x1f/0x30
value changed: 0x00 -> 0x02
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4872 Comm: kworker/0:0 Not tainted 5.17.0-rc3-syzkaller-00188-g1d41d2e82623-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events nsim_fib_event_work
Fixes: 90b93f1b31 ("ipv4: Add "offload" and "trap" indications to routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20220216173217.3792411-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the new dscp_t type to replace the fa_tos field of fib_alias. This
ensures ECN bits are ignored and makes the field compatible with the
fc_dscp field of struct fib_config.
Converting old *tos variables and fields to dscp_t allows sparse to
flag incorrect uses of DSCP and ECN bits. This patch is entirely about
type annotation and shouldn't change any existing behaviour.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use kvzalloc()/kvfree() instead of hand coded functions.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/fib_semantics.c uses a hash table (fib_info_laddrhash)
in which fib_sync_down_addr() can locate fib_info
based on IPv4 local address.
This hash table is resized based on total number of
hashed fib_info, but the hash function is only
using the local address.
For hosts having many active network namespaces,
all fib_info for loopback devices (IPv4 address 127.0.0.1)
are hashed into a single bucket, making netns dismantles
very slow.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/ipv4/fib_semantics.c uses an hash table of 256 slots,
keyed by device ifindexes: fib_info_devhash[DEVINDEX_HASHSIZE]
Problem is that with network namespaces, devices tend
to use the same ifindex.
lo device for instance has a fixed ifindex of one,
for all network namespaces.
This means that hosts with thousands of netns spend
a lot of time looking at some hash buckets with thousands
of elements, notably at netns dismantle.
Simply add a per netns perturbation (net_hash_mix())
to spread elements more uniformely.
Also change fib_devindex_hashfn() to use more entropy.
Fixes: aa79e66eee ("net: Make ifindex generation per-net namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In the past, free_fib_info() was supposed to be called
under RTNL protection.
This eventually was no longer the case.
Instead of enforcing RTNL it seems we simply can
move fib_info_cnt changes to occur when fib_info_lock
is held.
v2: David Laight suggested to update fib_info_cnt
only when an entry is added/deleted to/from the hash table,
as fib_info_cnt is used to make sure hash table size
is optimal.
BUG: KCSAN: data-race in fib_create_info / free_fib_info
write to 0xffffffff86e243a0 of 4 bytes by task 26429 on cpu 0:
fib_create_info+0xe78/0x3440 net/ipv4/fib_semantics.c:1428
fib_table_insert+0x148/0x10c0 net/ipv4/fib_trie.c:1224
fib_magic+0x195/0x1e0 net/ipv4/fib_frontend.c:1087
fib_add_ifaddr+0xd0/0x2e0 net/ipv4/fib_frontend.c:1109
fib_netdev_event+0x178/0x510 net/ipv4/fib_frontend.c:1466
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0x53/0xb0 kernel/notifier.c:391
__dev_notify_flags+0x1d3/0x3b0
dev_change_flags+0xa2/0xc0 net/core/dev.c:8872
do_setlink+0x810/0x2410 net/core/rtnetlink.c:2719
rtnl_group_changelink net/core/rtnetlink.c:3242 [inline]
__rtnl_newlink net/core/rtnetlink.c:3396 [inline]
rtnl_newlink+0xb10/0x13b0 net/core/rtnetlink.c:3506
rtnetlink_rcv_msg+0x745/0x7e0 net/core/rtnetlink.c:5571
netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2496
rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5589
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x726/0x840 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg net/socket.c:724 [inline]
____sys_sendmsg+0x39a/0x510 net/socket.c:2409
___sys_sendmsg net/socket.c:2463 [inline]
__sys_sendmsg+0x195/0x230 net/socket.c:2492
__do_sys_sendmsg net/socket.c:2501 [inline]
__se_sys_sendmsg net/socket.c:2499 [inline]
__x64_sys_sendmsg+0x42/0x50 net/socket.c:2499
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
read to 0xffffffff86e243a0 of 4 bytes by task 31505 on cpu 1:
free_fib_info+0x35/0x80 net/ipv4/fib_semantics.c:252
fib_info_put include/net/ip_fib.h:575 [inline]
nsim_fib4_rt_destroy drivers/net/netdevsim/fib.c:294 [inline]
nsim_fib4_rt_replace drivers/net/netdevsim/fib.c:403 [inline]
nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:431 [inline]
nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline]
nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline]
nsim_fib_event_work+0x15ca/0x2cf0 drivers/net/netdevsim/fib.c:1477
process_one_work+0x3fc/0x980 kernel/workqueue.c:2298
process_scheduled_works kernel/workqueue.c:2361 [inline]
worker_thread+0x7df/0xa70 kernel/workqueue.c:2447
kthread+0x2c7/0x2e0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30
value changed: 0x00000d2d -> 0x00000d2e
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 31505 Comm: kworker/1:21 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events nsim_fib_event_work
Fixes: 48bb9eb47b ("netdevsim: fib: Add dummy implementation for FIB offload")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Ido Schimmel <idosch@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
lwtunnel_valid_encap_type_attr is used to validate encap attributes
within a multipath route. Add length validation checking to the type.
lwtunnel_valid_encap_type_attr is called converting attributes to
fib{6,}_config struct which means it is used before fib_get_nhs,
ip6_route_multipath_add, and ip6_route_multipath_del - other
locations that use rtnh_ok and then nla_get_u16 on RTA_ENCAP_TYPE
attribute.
Fixes: 9ed59592e3 ("lwtunnel: fix autoload of lwt modules")
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure RTA_FLOW is at least 4B before using.
Fixes: 4e902c5741 ("[IPv4]: FIB configuration using struct fib_config")
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzbot reported uninit-value:
============================================================
BUG: KMSAN: uninit-value in fib_get_nhs+0xac4/0x1f80
net/ipv4/fib_semantics.c:708
fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708
fib_create_info+0x2411/0x4870 net/ipv4/fib_semantics.c:1453
fib_table_insert+0x45c/0x3a10 net/ipv4/fib_trie.c:1224
inet_rtm_newroute+0x289/0x420 net/ipv4/fib_frontend.c:886
Add helper to validate RTA_GATEWAY length before using the attribute.
Fixes: 4e902c5741 ("[IPv4]: FIB configuration using struct fib_config")
Reported-by: syzbot+d4b9a2851cc3ce998741@syzkaller.appspotmail.com
Signed-off-by: David Ahern <dsahern@kernel.org>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before commit faa041a40b ("ipv4: Create cleanup helper for fib_nh")
changes to net->ipv4.fib_num_tclassid_users were protected by RTNL.
After the change, this is no longer the case, as free_fib_info_rcu()
runs after rcu grace period, without rtnl being held.
Fixes: faa041a40b ("ipv4: Create cleanup helper for fib_nh")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Multipath RTA_FLOW is embedded in nexthop. Dump it in fib_add_nexthop()
to get the length of rtnexthop correct.
Fixes: b0f6019363 ("ipv4: Refactor nexthop attributes in fib_dump_info")
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ioana reported a refcount warning when booting over NFS:
[ 5.042532] ------------[ cut here ]------------
[ 5.047184] refcount_t: addition on 0; use-after-free.
[ 5.052324] WARNING: CPU: 7 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0xa4/0x150
...
[ 5.167201] Call trace:
[ 5.169635] refcount_warn_saturate+0xa4/0x150
[ 5.174067] fib_create_info+0xc00/0xc90
[ 5.177982] fib_table_insert+0x8c/0x620
[ 5.181893] fib_magic.isra.0+0x110/0x11c
[ 5.185891] fib_add_ifaddr+0xb8/0x190
[ 5.189629] fib_inetaddr_event+0x8c/0x140
fib_treeref needs to be set after kzalloc. The old code had a ++ which
led to the confusion when the int was replaced by a refcount_t.
Fixes: 79976892f7 ("net: convert fib_treeref from int to refcount_t")
Signed-off-by: David Ahern <dsahern@kernel.org>
Reported-by: Ioana Ciornei <ciorneiioana@gmail.com>
Cc: Yajun Deng <yajun.deng@linux.dev>
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20210802160221.27263-1-dsahern@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
refcount_t type should be used instead of int when fib_treeref is used as
a reference counter,and avoid use-after-free risks.
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20210729071350.28919-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple break statements instead of just
letting the code fall through to the next case.
Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
After installing a route to the kernel, user space receives an
acknowledgment, which means the route was installed in the kernel, but not
necessarily in hardware.
The asynchronous nature of route installation in hardware can lead to a
routing daemon advertising a route before it was actually installed in
hardware. This can result in packet loss or mis-routed packets until the
route is installed in hardware.
To avoid such cases, previous patch set added the ability to emit
RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags
are changed, this behavior is controlled by sysctl.
With the above mentioned behavior, it is possible to know from user-space
if the route was offloaded, but if the offload fails there is no indication
to user-space. Following a failure, a routing daemon will wait indefinitely
for a notification that will never come.
This patch adds an "offload_failed" indication to IPv4 routes, so that
users will have better visibility into the offload process.
'struct fib_alias', and 'struct fib_rt_info' are extended with new field
that indicates if route offload failed. Note that the new field is added
using unused bit and therefore there is no need to increase structs size.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Publish fib_nlmsg_size() to allow it to be used later on from
fib_alias_hw_flags_set().
Remove the inline keyword since it shouldn't be used inside C files.
Signed-off-by: Amit Cohen <amcohen@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>
fib_dump_info() does not change 'fri', so pass it as 'const'.
It will later allow us to invoke fib_dump_info() from
fib_alias_hw_flags_set().
Signed-off-by: Amit Cohen <amcohen@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>
Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new
name of this function.
Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Be more consistent about the way in which the nexthop flags are set and
set them in one go.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20201110102553.1924232-1-idosch@idosch.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The flag indicates to user space that the nexthop is not programmed to
forward packets in hardware, but rather to trap them to the CPU. This is
needed, for example, when the MAC of the nexthop neighbour is not
resolved and packets should reach the CPU to trigger neighbour
resolution.
The flag will be used in subsequent patches by netdevsim to test nexthop
objects programming to device drivers and in the future by mlxsw as
well.
Changes since RFC:
* Reword commit message
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ie.,
$ ifconfig eth0 6.6.6.6 netmask 255.255.255.0
$ ip rule add from 6.6.6.6 table 6666
$ ip route add 9.9.9.9 via 6.6.6.6
$ ping -I 6.6.6.6 9.9.9.9
PING 9.9.9.9 (9.9.9.9) from 6.6.6.6 : 56(84) bytes of data.
3 packets transmitted, 0 received, 100% packet loss, time 2079ms
$ arp
Address HWtype HWaddress Flags Mask Iface
6.6.6.6 (incomplete) eth0
The arp request address is error, this is because fib_table_lookup in
fib_check_nh lookup the destnation 9.9.9.9 nexthop, the scope of
the fib result is RT_SCOPE_LINK,the correct scope is RT_SCOPE_HOST.
Here I add a check of whether this is RT_TABLE_MAIN to solve this problem.
Fixes: 3bfd847203 ("net: Use passed in table for nexthop lookups")
Signed-off-by: guodeqing <geffrey.guo@huawei.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current route nexthop API maintains user space compatibility
with old route API by default. Dumps and netlink notifications
support both new and old API format. In systems which have
moved to the new API, this compatibility mode cancels some
of the performance benefits provided by the new nexthop API.
This patch adds new sysctl nexthop_compat_mode which is on
by default but provides the ability to turn off compatibility
mode allowing systems to run entirely with the new routing
API. Old route API behaviour and support is not modified by this
sysctl.
Uses a single sysctl to cover both ipv4 and ipv6 following
other sysctls. Covers dumps and delete notifications as
suggested by David Ahern.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The build_state callback of lwtunnel doesn't contain the net namespace
structure yet. This patch will add it so we can check on specific
address configuration at creation time of rpl source routes.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert the various uses of fallthrough comments to fallthrough;
Done via script
Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/
And by hand:
net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block
that causes gcc to emit a warning if converted in-place.
So move the new fallthrough; inside the containing #ifdef/#endif too.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When performing L3 offload, routes and nexthops are usually programmed
into two different tables in the underlying device. Therefore, the fact
that a nexthop resides in hardware does not necessarily mean that all
the associated routes also reside in hardware and vice-versa.
While the kernel can signal to user space the presence of a nexthop in
hardware (via 'RTNH_F_OFFLOAD'), it does not have a corresponding flag
for routes. In addition, the fact that a route resides in hardware does
not necessarily mean that the traffic is offloaded. For example,
unreachable routes (i.e., 'RTN_UNREACHABLE') are programmed to trap
packets to the CPU so that the kernel will be able to generate the
appropriate ICMP error packet.
This patch adds an "offload" and "trap" indications to IPv4 routes, so
that users will have better visibility into the offload process.
'struct fib_alias' is extended with two new fields that indicate if the
route resides in hardware or not and if it is offloading traffic from
the kernel or trapping packets to it. Note that the new fields are added
in the 6 bytes hole and therefore the struct still fits in a single
cache line [1].
Capable drivers are expected to invoke fib_alias_hw_flags_set() with the
route's key in order to set the flags.
The indications are dumped to user space via a new flags (i.e.,
'RTM_F_OFFLOAD' and 'RTM_F_TRAP') in the 'rtm_flags' field in the
ancillary header.
v2:
* Make use of 'struct fib_rt_info' in fib_alias_hw_flags_set()
[1]
struct fib_alias {
struct hlist_node fa_list; /* 0 16 */
struct fib_info * fa_info; /* 16 8 */
u8 fa_tos; /* 24 1 */
u8 fa_type; /* 25 1 */
u8 fa_state; /* 26 1 */
u8 fa_slen; /* 27 1 */
u32 tb_id; /* 28 4 */
s16 fa_default; /* 32 2 */
u8 offload:1; /* 34: 0 1 */
u8 trap:1; /* 34: 1 1 */
u8 unused:6; /* 34: 2 1 */
/* XXX 5 bytes hole, try to pack */
struct callback_head rcu __attribute__((__aligned__(8))); /* 40 16 */
/* size: 56, cachelines: 1, members: 12 */
/* sum members: 50, holes: 1, sum holes: 5 */
/* sum bitfield members: 8 bits (1 bytes) */
/* forced alignments: 1, forced holes: 1, sum forced holes: 5 */
/* last cacheline: 56 bytes */
} __attribute__((__aligned__(8)));
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib_dump_info() is used to prepare RTM_{NEW,DEL}ROUTE netlink messages
using the passed arguments. Currently, the function takes 11 arguments,
6 of which are attributes of the route being dumped (e.g., prefix, TOS).
The next patch will need the function to also dump to user space an
indication if the route is present in hardware or not. Instead of
passing yet another argument, change the function to take a struct
containing the different route attributes.
v2:
* Name last argument of fib_dump_info()
* Move 'struct fib_rt_info' to include/net/ip_fib.h so that it could
later be passed to fib_alias_hw_flags_set()
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hendrik reported routes in the main table using source address are not
removed when the address is removed. The problem is that fib_sync_down_addr
does not account for devices in the default VRF which are associated
with the main table. Fix by updating the table id reference.
Fixes: 5a56a0b3a4 ("net: Don't delete routes in different VRFs")
Reported-by: Hendrik Donner <hd@os-cillation.de>
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When creating a v4 route that uses a v6 nexthop from a nexthop group.
Allow the kernel to properly send the nexthop as v6 via the RTA_VIA
attribute.
Broken behavior:
$ ip nexthop add via fe80::9 dev eth0
$ ip nexthop show
id 1 via fe80::9 dev eth0 scope link
$ ip route add 4.5.6.7/32 nhid 1
$ ip route show
default via 10.0.2.2 dev eth0
4.5.6.7 nhid 1 via 254.128.0.0 dev eth0
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15
$
Fixed behavior:
$ ip nexthop add via fe80::9 dev eth0
$ ip nexthop show
id 1 via fe80::9 dev eth0 scope link
$ ip route add 4.5.6.7/32 nhid 1
$ ip route show
default via 10.0.2.2 dev eth0
4.5.6.7 nhid 1 via inet6 fe80::9 dev eth0
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15
$
v2, v3: Addresses code review comments from David Ahern
Fixes: dcb1ecb50e (“ipv4: Prepare for fib6_nh from a nexthop object”)
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet