linux-toradex.git/include/net/ip6_fib.h, branch v6.19

ipv6: Defer fib6_purge_rt() in fib6_add_rt2node() to fib6_add().

2025-04-24T07:29:56+00:00

The next patch adds per-nexthop spinlock which protects nh->f6i_list.

When rt->nh is not NULL, fib6_add_rt2node() will be called under the lock.
fib6_add_rt2node() could call fib6_purge_rt() for another route, which
could holds another nexthop lock.

Then, deadlock could happen between two nexthops.

Let's defer fib6_purge_rt() after fib6_add_rt2node().

Signed-off-by: Kuniyuki Iwashima 
Acked-by: Paolo Abeni 
Link: https://patch.msgid.link/20250418000443.43734-14-kuniyu@amazon.com
Signed-off-by: Paolo Abeni

ipv6: use READ_ONCE()/WRITE_ONCE() on fib6_table->fib_seq

2024-10-11T22:35:05+00:00

Using RTNL to protect ops->fib_rules_seq reads seems a big hammer.

Writes are protected by RTNL.
We can use READ_ONCE() when reading it.

Constify 'struct net' argument of fib6_tables_seq_read() and
fib6_rules_seq_read().

Signed-off-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Reviewed-by: David Ahern 
Link: https://patch.msgid.link/20241009184405.3752829-4-edumazet@google.com
Signed-off-by: Jakub Kicinski

ipv6: introduce dst_rt6_info() helper

2024-04-29T12:32:01+00:00

Instead of (struct rt6_info *)dst casts, we can use :

 #define dst_rt6_info(_ptr) \
         container_of_const(_ptr, struct rt6_info, dst)

Some places needed missing const qualifiers :

ip6_confirm_neigh(), ipv6_anycast_destination(),
ipv6_unicast_destination(), has_gateway()

v2: added missing parts (David Ahern)

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

ipv6: use call_rcu_hurry() in fib6_info_release()

2024-04-29T09:03:51+00:00

This is a followup of commit c4e86b4363ac ("net: add two more
call_rcu_hurry()")

fib6_info_destroy_rcu() is calling nexthop_put() or fib6_nh_release()

We must not delay it too much or risk unregister_netdevice/ref_tracker
traces because references to netdev are not released in time.

This should speedup device/netns dismantles when CONFIG_RCU_LAZY=y

Signed-off-by: Eric Dumazet 
Reviewed-by: Jiri Pirko 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

net/ipv6: Remove expired routes with a separated list of routes.

2024-02-12T10:24:12+00:00

FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is big, even if most of
them are permanent. Checking routes in a separated list of routes having
expiration will avoid this potential issue.

Reviewed-by: David Ahern 
Signed-off-by: Kui-Feng Lee 
Signed-off-by: David S. Miller

net/ipv6: resolve warning in ip6_fib.c

2024-01-24T01:22:23+00:00

In some configurations, the 'iter' variable in function
fib6_repair_tree() is unused, resulting the following warning when
compiled with W=1.

    net/ipv6/ip6_fib.c:1781:6: warning: variable 'iter' set but not used [-Wunused-but-set-variable]
     1781 |         int iter = 0;
	  |             ^

It is unclear what is the advantage of this RT6_TRACE() macro[1], since
users can control pr_debug() in runtime, which is better than at
compilation time. pr_debug() has no overhead when disabled.

Remove the RT6_TRACE() in favor of simple pr_debug() helpers.

[1] Link: https://lore.kernel.org/all/ZZwSEJv2HgI0cD4J@gmail.com/
Signed-off-by: Breno Leitao 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20240122181955.2391676-2-leitao@debian.org
Signed-off-by: Jakub Kicinski

net/ipv6: Revert remove expired routes with a separated list of routes

2023-12-21T08:01:30+00:00

This reverts commit 3dec89b14d37ee635e772636dad3f09f78f1ab87.

The commit has some race conditions given how expires is managed on a
fib6_info in relation to gc start, adding the entry to the gc list and
setting the timer value leading to UAF. Revert the commit and try again
in a later release.

Fixes: 3dec89b14d37 ("net/ipv6: Remove expired routes with a separated list of routes")
Cc: Kui-Feng Lee 
Signed-off-by: David Ahern 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20231219030243.25687-1-dsahern@kernel.org
Signed-off-by: Paolo Abeni

net: fib: avoid warn splat in flow dissector

2023-08-31T10:33:03+00:00

New skbs allocated via nf_send_reset() have skb->dev == NULL.

fib*_rules_early_flow_dissect helpers already have a 'struct net'
argument but its not passed down to the flow dissector core, which
will then WARN as it can't derive a net namespace to use:

 WARNING: CPU: 0 PID: 0 at net/core/flow_dissector.c:1016 __skb_flow_dissect+0xa91/0x1cd0
 [..]
  ip_route_me_harder+0x143/0x330
  nf_send_reset+0x17c/0x2d0 [nf_reject_ipv4]
  nft_reject_inet_eval+0xa9/0xf2 [nft_reject_inet]
  nft_do_chain+0x198/0x5d0 [nf_tables]
  nft_do_chain_inet+0xa4/0x110 [nf_tables]
  nf_hook_slow+0x41/0xc0
  ip_local_deliver+0xce/0x110
  ..

Cc: Stanislav Fomichev 
Cc: David Ahern 
Cc: Ido Schimmel 
Fixes: 812fa71f0d96 ("netfilter: Dissect flow after packet mangling")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217826
Signed-off-by: Florian Westphal 
Reviewed-by: Ido Schimmel 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20230830110043.30497-1-fw@strlen.de
Signed-off-by: Paolo Abeni

net/ipv6: Remove expired routes with a separated list of routes.

2023-08-16T11:26:43+00:00

FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is big, even if most of
them are permanent. Checking routes in a separated list of routes having
expiration will avoid this potential issue.

Signed-off-by: Kui-Feng Lee 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller

ipv6: Remove in6addr_any alternatives.

2023-03-29T07:22:52+00:00

Some code defines the IPv6 wildcard address as a local variable and
use it with memcmp() or ipv6_addr_equal().

Let's use in6addr_any and ipv6_addr_any() instead.

Signed-off-by: Kuniyuki Iwashima 
Reviewed-by: Mark Bloch 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller