Commit cc34acd577 ("docs: net: document new locking reality")
introduced netif_ vs dev_ function semantics: the former expects locked
netdev, the latter takes care of the locking. We don't strictly
follow this semantics on either side, but there are more dev_xxx handlers
now that don't fit. Rename them to netif_xxx where appropriate.
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250717172333.1288349-6-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
lwtunnel_build_state() has check validity of encap_type,
so no need to do this before call it.
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250625022059.3958215-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
lwtunnel_fill_encap() has NULL check and return 0, so no need
to check before call it.
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250624140015.3929241-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
These two commits preallocated two per-cpu variables in
ip6_route_info_create() as fib_nh_common_init() and fib6_nh_init()
were expected to be called under RCU.
* commit d27b9c40db ("ipv6: Preallocate nhc_pcpu_rth_output in
ip6_route_info_create().")
* commit 5720a328c3 ("ipv6: Preallocate rt->fib6_nh->rt6i_pcpu in
ip6_route_info_create().")
Now these functions can be called without RCU and can use GFP_KERNEL.
Let's revert the commits.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250516022759.44392-8-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 32607a332c ("ipv4: prefer multipath nexthop that matches source
address") changed IPv4 nexthop selection to prefer a nexthop whose
nexthop device is assigned the specified source address for locally
generated traffic.
While the selection honors the "fib_multipath_use_neigh" sysctl and will
not choose a nexthop with an invalid neighbour, it does not honor the
"ignore_routes_with_linkdown" sysctl and can choose a nexthop without a
carrier:
$ sysctl net.ipv4.conf.all.ignore_routes_with_linkdown
net.ipv4.conf.all.ignore_routes_with_linkdown = 1
$ ip route show 198.51.100.0/24
198.51.100.0/24
nexthop via 192.0.2.2 dev dummy1 weight 1
nexthop via 192.0.2.18 dev dummy2 weight 1 dead linkdown
$ ip route get 198.51.100.1 from 192.0.2.17
198.51.100.1 from 192.0.2.17 via 192.0.2.18 dev dummy2 uid 0
Solve this by skipping over nexthops whose assigned hash upper bound is
minus one, which is the value assigned to nexthops that do not have a
carrier when the "ignore_routes_with_linkdown" sysctl is set.
In practice, this probably does not matter a lot as the initial route
lookup for the source address would not choose a nexthop that does not
have a carrier in the first place, but the change does make the code
clearer.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for making the kmalloc family of allocators type aware,
we need to make sure that the returned type from the allocation matches
the type of the variable being assigned. (Before, the allocator would
always return "void *", which can be implicitly cast to any pointer type.)
This was allocating many sizeof(struct hlist_head *) when it actually
wanted sizeof(struct hlist_head). Luckily these are the same size.
Adjust the allocation type to match the assignment.
Signed-off-by: Kees Cook <kees@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250426060529.work.873-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
With multipath routes, try to ensure that packets leave on the device
that is associated with the source address.
Avoid the following tcpdump example:
veth0 Out IP 10.1.0.2.38640 > 10.2.0.3.8000: Flags [S]
veth1 Out IP 10.1.0.2.38648 > 10.2.0.3.8000: Flags [S]
Which can happen easily with the most straightforward setup:
ip addr add 10.0.0.1/24 dev veth0
ip addr add 10.1.0.1/24 dev veth1
ip route add 10.2.0.3 nexthop via 10.0.0.2 dev veth0 \
nexthop via 10.1.0.2 dev veth1
This is apparently considered WAI, based on the comment in
ip_route_output_key_hash_rcu:
* 2. Moreover, we are allowed to send packets with saddr
* of another iface. --ANK
It may be ok for some uses of multipath, but not all. For instance,
when using two ISPs, a router may drop packets with unknown source.
The behavior occurs because tcp_v4_connect makes three route
lookups when establishing a connection:
1. ip_route_connect calls to select a source address, with saddr zero.
2. ip_route_connect calls again now that saddr and daddr are known.
3. ip_route_newports calls again after a source port is also chosen.
With a route with multiple nexthops, each lookup may make a different
choice depending on available entropy to fib_select_multipath. So it
is possible for 1 to select the saddr from the first entry, but 3 to
select the second entry. Leading to the above situation.
Address this by preferring a match that matches the flowi4 saddr. This
will make 2 and 3 make the same choice as 1. Continue to update the
backup choice until a choice that matches saddr is found.
Do this in fib_select_multipath itself, rather than passing an fl4_oif
constraint, to avoid changing non-multipath route selection. Commit
e6b45241c5 ("ipv4: reset flowi parameters on route connect") shows
how that may cause regressions.
Also read ipv4.sysctl_fib_multipath_use_neigh only once. No need to
refresh in the loop.
This does not happen in IPv6, which performs only one lookup.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250424143549.669426-2-willemdebruijn.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ip6_route_info_create_nh() will be called under RCU.
It calls fib_nh_common_init() and allocates nhc->nhc_pcpu_rth_output.
As with the reason for rt->fib6_nh->rt6i_pcpu, we want to avoid
GFP_ATOMIC allocation for nhc->nhc_pcpu_rth_output under RCU.
Let's preallocate it in ip6_route_info_create().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-9-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.
Then, we need to have per-netns hash tables for struct fib_info.
Let's allocate the hash tables per netns.
fib_info_hash, fib_info_hash_bits, and fib_info_cnt are now moved
to struct netns_ipv4 and accessed with net->ipv4.fib_XXX.
Also, the netns checks are removed from fib_find_info_nh() and
fib_find_info().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-9-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When the number of struct fib_info exceeds the hash table size in
fib_create_info(), we try to allocate a new hash table with the
doubled size.
The allocation is done in fib_create_info(), and if successful, each
struct fib_info is moved to the new hash table by fib_info_hash_move().
Let's integrate the allocation and fib_info_hash_move() as
fib_info_hash_grow() to make the following change cleaner.
While at it, fib_info_hash_grow() is placed near other hash-table-specific
functions.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-8-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will allocate the fib_info hash tables per netns.
There are 5 global variables for fib_info hash tables:
fib_info_hash, fib_info_laddrhash, fib_info_hash_size,
fib_info_hash_bits, fib_info_cnt.
However, fib_info_laddrhash and fib_info_hash_size can be
easily calculated from fib_info_hash and fib_info_hash_bits.
Let's remove fib_info_hash_size and use (1 << fib_info_hash_bits)
instead.
Now we need not pass the new hash table size to fib_info_hash_move().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-7-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will allocate the fib_info hash tables per netns.
There are 5 global variables for fib_info hash tables:
fib_info_hash, fib_info_laddrhash, fib_info_hash_size,
fib_info_hash_bits, fib_info_cnt.
However, fib_info_laddrhash and fib_info_hash_size can be
easily calculated from fib_info_hash and fib_info_hash_bits.
Let's remove the fib_info_laddrhash pointer and instead use
fib_info_hash + (1 << fib_info_hash_bits).
While at it, fib_info_laddrhash_bucket() is moved near other
hash-table-specific functions.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-6-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Every time fib_info_hashfn() returns a hash value, we fetch
&fib_info_hash[hash].
Let's return the hlist_head pointer from fib_info_hashfn() and
rename it to fib_info_hash_bucket() to match a similar function,
fib_info_laddrhash_bucket().
Note that we need to move the fib_info_hash assignment earlier in
fib_info_hash_move() to use fib_info_hash_bucket() in the for loop.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-5-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will allocate fib_info_hash[] and fib_info_laddrhash[] for each netns.
Currently, fib_info_hash[] is allocated when the first route is added.
Let's move the first allocation to a new __net_init function.
Note that we must call fib4_semantics_exit() in fib_net_exit_batch()
because ->exit() is called earlier than ->exit_batch().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Both fib_info_hash[] and fib_info_laddrhash[] are hash tables for
struct fib_info and are allocated by kvzmalloc() separately.
Let's replace the two kvzmalloc() calls with kvcalloc() to remove
the fib_info_laddrhash pointer later.
Note that fib_info_hash_alloc() allocates a new hash table based on
fib_info_hash_bits because we will remove fib_info_hash_size later.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250228042328.96624-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Upcoming per-netns RTNL conversion needs to get rid
of shared hash tables.
fib_info_devhash[] is one of them.
It is unclear why we used a hash table, because
a single hlist_head per net device was cheaper and scalable.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241004134720.579244-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After the prior patch, fib_info_lock became redundant
because all of its users are holding RTNL.
BH protection is not needed.
Remove the READ_ONCE()/WRITE_ONCE() annotations around fib_info_cnt,
since it is protected by RTNL.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241004134720.579244-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
fib_info_devhash[] is not resized in fib_info_hash_move().
fib_nh structs are already freed after an rcu grace period.
This will allow to remove fib_info_lock in the following patch.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241004134720.579244-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
fib_devindex_hashfn() converts a 32bit ifindex value to a 8bit hash.
It makes no sense doing this from fib_info_hashfn() and
fib_find_info_nh().
It is better to keep as many bits as possible to let
fib_info_hashfn_result() have better spread.
Only fib_info_devhash_bucket() needs to make this operation,
we can 'inline' trivial fib_devindex_hashfn() in it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241004134720.579244-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Mix netns into all IPv4 FIB hashes to avoid massive collision when
inserting the same address in many netns.
Signed-off-by: Alexandre Ferrieux <alexandre.ferrieux@orange.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241001231438.3855035-1-alexandre.ferrieux@orange.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The initial value of err is -ENOBUFS, and err is guaranteed to be
less than 0 before all goto errout. Therefore, on the error path
of errout, there is no need to repeatedly judge that err is less than 0,
and delete redundant judgments to make the code more concise.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TOS field in the IPv4 flow information structure ('flowi4_tos') is
matched by the kernel against the TOS selector in IPv4 rules and routes.
The field is initialized differently by different call sites. Some treat
it as DSCP (RFC 2474) and initialize all six DSCP bits, some treat it as
RFC 1349 TOS and initialize it using RT_TOS() and some treat it as RFC
791 TOS and initialize it using IPTOS_RT_MASK.
What is common to all these call sites is that they all initialize the
lower three DSCP bits, which fits the TOS definition in the initial IPv4
specification (RFC 791).
Therefore, the kernel only allows configuring IPv4 FIB rules that match
on the lower three DSCP bits which are always guaranteed to be
initialized by all call sites:
# ip -4 rule add tos 0x1c table 100
# ip -4 rule add tos 0x3c table 100
Error: Invalid tos.
While this works, it is unlikely to be very useful. RFC 791 that
initially defined the TOS and IP precedence fields was updated by RFC
2474 over twenty five years ago where these fields were replaced by a
single six bits DSCP field.
Extending FIB rules to match on DSCP can be done by adding a new DSCP
selector while maintaining the existing semantics of the TOS selector
for applications that rely on that.
A prerequisite for allowing FIB rules to match on DSCP is to adjust all
the call sites to initialize the high order DSCP bits and remove their
masking along the path to the core where the field is matched on.
However, making this change alone will result in a behavior change. For
example, a forwarded IPv4 packet with a DS field of 0xfc will no longer
match a FIB rule that was configured with 'tos 0x1c'.
This behavior change can be avoided by masking the upper three DSCP bits
in 'flowi4_tos' before comparing it against the TOS selectors in FIB
rules and routes.
Implement the above by adding a new function that checks whether a given
DSCP value matches the one specified in the IPv4 flow information
structure and invoke it from the three places that currently match on
'flowi4_tos'.
Use RT_TOS() for the masking of 'flowi4_tos' instead of IPTOS_RT_MASK
since the latter is not uAPI and we should be able to remove it at some
point.
Include <linux/ip.h> in <linux/in_route.h> since the former defines
IPTOS_TOS_MASK which is used in the definition of RT_TOS() in
<linux/in_route.h>.
No regressions in FIB tests:
# ./fib_tests.sh
[...]
Tests passed: 218
Tests failed: 0
And FIB rule tests:
# ./fib_rule_tests.sh
[...]
Tests passed: 116
Tests failed: 0
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Merge in late fixes to prepare for the 6.11 net-next PR.
Conflicts:
93c3a96c30 ("net: pse-pd: Do not return EOPNOSUPP if config is null")
4cddb0f15e ("net: ethtool: pse-pd: Fix possible null-deref")
30d7b67277 ("net: ethtool: Add new power limit get and set features")
https://lore.kernel.org/20240715123204.623520bb@canb.auug.org.au/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
By default, an address assigned to the output interface is selected when
the source address is not specified. This is problematic when a route,
configured in a vrf, uses an interface from another vrf (aka route leak).
The original vrf does not own the selected source address.
Let's add a check against the output interface and call the appropriate
function to select the source address.
CC: stable@vger.kernel.org
Fixes: 8cbb512c92 ("net: Add source address lookup op for VRF")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240710081521.3809742-2-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When I was doing some experiments, I found that when using the first
parameter, namely, struct net, in ip_metrics_convert() always triggers NULL
pointer crash. Then I digged into this part, realizing that we can remove
this one due to its uselessness.
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
After deleting an interface address in fib_del_ifaddr(), the function
scans the fib_info list for stray entries and calls fib_flush() and
fib_table_flush(). Then the stray entries will be deleted silently and no
RTM_DELROUTE notification will be sent.
This lack of notification can make routing daemons, or monitor like
`ip monitor route` miss the routing changes. e.g.
+ ip link add dummy1 type dummy
+ ip link add dummy2 type dummy
+ ip link set dummy1 up
+ ip link set dummy2 up
+ ip addr add 192.168.5.5/24 dev dummy1
+ ip route add 7.7.7.0/24 dev dummy2 src 192.168.5.5
+ ip -4 route
7.7.7.0/24 dev dummy2 scope link src 192.168.5.5
192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5
As Ido reminded, fib_table_flush() isn't only called when an address is
deleted, but also when an interface is deleted or put down. The lack of
notification in these cases is deliberate. And commit 7c6bb7d2fa
("net/ipv6: Add knob to skip DELROUTE message on device down") introduced
a sysctl to make IPv6 behave like IPv4 in this regard. So we can't send
the route delete notify blindly in fib_table_flush().
To fix this issue, let's add a new flag in "struct fib_info" to track the
deleted prefer source address routes, and only send notify for them.
After update:
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5
Deleted 7.7.7.0/24 dev dummy2 scope link src 192.168.5.5
Suggested-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230922075508.848925-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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>
