hmac_storage is a per-CPU variable and relies on disabled BH for its
locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT
this data structure requires explicit locking.
Add a local_lock_t to the data structure and use
local_lock_nested_bh() for locking. This change adds only lockdep
coverage and does not alter the functional behaviour for !PREEMPT_RT.
Cc: David Ahern <dsahern@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20250512092736.229935-5-bigeasy@linutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Augment dmabuf binding to be able to handle TX. Additional to all the RX
binding, we also create tx_vec needed for the TX path.
Provide API for sendmsg to be able to send dmabufs bound to this device:
- Provide a new dmabuf_tx_cmsg which includes the dmabuf to send from.
- MSG_ZEROCOPY with SCM_DEVMEM_DMABUF cmsg indicates send from dma-buf.
Devmem is uncopyable, so piggyback off the existing MSG_ZEROCOPY
implementation, while disabling instances where MSG_ZEROCOPY falls back
to copying.
We additionally pipe the binding down to the new
zerocopy_fill_skb_from_devmem which fills a TX skb with net_iov netmems
instead of the traditional page netmems.
We also special case skb_frag_dma_map to return the dma-address of these
dmabuf net_iovs instead of attempting to map pages.
The TX path may release the dmabuf in a context where we cannot wait.
This happens when the user unbinds a TX dmabuf while there are still
references to its netmems in the TX path. In that case, the netmems will
be put_netmem'd from a context where we can't unmap the dmabuf, Resolve
this by making __net_devmem_dmabuf_binding_free schedule_work'd.
Based on work by Stanislav Fomichev <sdf@fomichev.me>. A lot of the meat
of the implementation came from devmem TCP RFC v1[1], which included the
TX path, but Stan did all the rebasing on top of netmem/net_iov.
Cc: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250508004830.4100853-5-almasrymina@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Use addrconf_addr_gen() to generate IPv6 link-local addresses on GRE
devices in most cases and fall back to using add_v4_addrs() only in
case the GRE configuration is incompatible with addrconf_addr_gen().
GRE used to use addrconf_addr_gen() until commit e5dd729460 ("ip/ip6_gre:
use the same logic as SIT interfaces when computing v6LL address")
restricted this use to gretap and ip6gretap devices, and created
add_v4_addrs() (borrowed from SIT) for non-Ethernet GRE ones.
The original problem came when commit 9af28511be ("addrconf: refuse
isatap eui64 for INADDR_ANY") made __ipv6_isatap_ifid() fail when its
addr parameter was 0. The commit says that this would create an invalid
address, however, I couldn't find any RFC saying that the generated
interface identifier would be wrong. Anyway, since gre over IPv4
devices pass their local tunnel address to __ipv6_isatap_ifid(), that
commit broke their IPv6 link-local address generation when the local
address was unspecified.
Then commit e5dd729460 ("ip/ip6_gre: use the same logic as SIT
interfaces when computing v6LL address") tried to fix that case by
defining add_v4_addrs() and calling it to generate the IPv6 link-local
address instead of using addrconf_addr_gen() (apart for gretap and
ip6gretap devices, which would still use the regular
addrconf_addr_gen(), since they have a MAC address).
That broke several use cases because add_v4_addrs() isn't properly
integrated into the rest of IPv6 Neighbor Discovery code. Several of
these shortcomings have been fixed over time, but add_v4_addrs()
remains broken on several aspects. In particular, it doesn't send any
Router Sollicitations, so the SLAAC process doesn't start until the
interface receives a Router Advertisement. Also, add_v4_addrs() mostly
ignores the address generation mode of the interface
(/proc/sys/net/ipv6/conf/*/addr_gen_mode), thus breaking the
IN6_ADDR_GEN_MODE_RANDOM and IN6_ADDR_GEN_MODE_STABLE_PRIVACY cases.
Fix the situation by using add_v4_addrs() only in the specific scenario
where the normal method would fail. That is, for interfaces that have
all of the following characteristics:
* run over IPv4,
* transport IP packets directly, not Ethernet (that is, not gretap
interfaces),
* tunnel endpoint is INADDR_ANY (that is, 0),
* device address generation mode is EUI64.
In all other cases, revert back to the regular addrconf_addr_gen().
Also, remove the special case for ip6gre interfaces in add_v4_addrs(),
since ip6gre devices now always use addrconf_addr_gen() instead.
Note:
This patch was originally applied as commit 183185a18f ("gre: Fix
IPv6 link-local address generation."). However, it was then reverted
by commit fc486c2d06 ("Revert "gre: Fix IPv6 link-local address
generation."") because it uncovered another bug that ended up
breaking net/forwarding/ip6gre_custom_multipath_hash.sh. That other
bug has now been fixed by commit 4d0ab3a688 ("ipv6: Start path
selection from the first nexthop"). Therefore we can now revive this
GRE patch (no changes since original commit 183185a18f ("gre: Fix
IPv6 link-local address generation.").
Fixes: e5dd729460 ("ip/ip6_gre: use the same logic as SIT interfaces when computing v6LL address")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/a88cc5c4811af36007645d610c95102dccb360a6.1746225214.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The config NF_CONNTRACK_BRIDGE will change the bridge forwarding for
fragmented packets.
The original bridge does not know that it is a fragmented packet and
forwards it directly, after NF_CONNTRACK_BRIDGE is enabled, function
nf_br_ip_fragment and br_ip6_fragment will check the headroom.
In original br_forward, insufficient headroom of skb may indeed exist,
but there's still a way to save the skb in the device driver after
dev_queue_xmit.So droping the skb will change the original bridge
forwarding in some cases.
Fixes: 3c171f496e ("netfilter: bridge: add connection tracking system")
Signed-off-by: Huajian Yang <huajianyang@asrmicro.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Load balance new TCP connections across nexthops also when they
connect to the same service at a single remote address and port.
This affects only port-based multipath hashing:
fib_multipath_hash_policy 1 or 3.
Local connections must choose both a source address and port when
connecting to a remote service, in ip_route_connect. This
"chicken-and-egg problem" (commit 2d7192d6cb ("ipv4: Sanitize and
simplify ip_route_{connect,newports}()")) is resolved by first
selecting a source address, by looking up a route using the zero
wildcard source port and address.
As a result multiple connections to the same destination address and
port have no entropy in fib_multipath_hash.
This is not a problem when forwarding, as skb-based hashing has a
4-tuple. Nor when establishing UDP connections, as autobind there
selects a port before reaching ip_route_connect.
Load balance also TCP, by using a random port in fib_multipath_hash.
Port assignment in inet_hash_connect is not atomic with
ip_route_connect. Thus ports are unpredictable, effectively random.
Implementation details:
Do not actually pass a random fl4_sport, as that affects not only
hashing, but routing more broadly, and can match a source port based
policy route, which existing wildcard port 0 will not. Instead,
define a new wildcard flowi flag that is used only for hashing.
Selecting a random source is equivalent to just selecting a random
hash entirely. But for code clarity, follow the normal 4-tuple hash
process and only update this field.
fib_multipath_hash can be reached with zero sport from other code
paths, so explicitly pass this flowi flag, rather than trying to infer
this case in the function itself.
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/20250424143549.669426-3-willemdebruijn.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Now we are ready to remove RTNL from SIOCADDRT and RTM_NEWROUTE.
The remaining things to do are
1. pass false to lwtunnel_valid_encap_type_attr()
2. use rcu_dereference_rtnl() in fib6_check_nexthop()
3. place rcu_read_lock() before ip6_route_info_create_nh().
Let's complete the RTNL-free conversion.
When each CPU-X adds 100000 routes on table-X in a batch
concurrently on c7a.metal-48xl EC2 instance with 192 CPUs,
without this series:
$ sudo ./route_test.sh
...
added 19200000 routes (100000 routes * 192 tables).
time elapsed: 191577 milliseconds.
with this series:
$ sudo ./route_test.sh
...
added 19200000 routes (100000 routes * 192 tables).
time elapsed: 62854 milliseconds.
I changed the number of routes in each table (1000 ~ 100000)
and consistently saw it finish 3x faster with this series.
Note that now every caller of lwtunnel_valid_encap_type() passes
false as the last argument, and this can be removed later.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-16-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT.
Then, we may be going to add a route tied to a dying nexthop.
The nexthop itself is not freed during the RCU grace period, but
if we link a route after __remove_nexthop_fib() is called for the
nexthop, the route will be leaked.
To avoid the race between IPv6 route addition under RCU vs nexthop
deletion under RTNL, let's add a dead flag and protect it and
nh->f6i_list with a spinlock.
__remove_nexthop_fib() acquires the nexthop's spinlock and sets false
to nh->dead, then calls ip6_del_rt() for the linked route one by one
without the spinlock because fib6_purge_rt() acquires it later.
While adding an IPv6 route, fib6_add() acquires the nexthop lock and
checks the dead flag just before inserting the route.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-15-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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 <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-14-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT.
If the request specifies a new table ID, fib6_new_table() is
called to create a new routing table.
Two concurrent requests could specify the same table ID, so we
need a lock to protect net->ipv6.fib_table_hash[h].
Let's add a spinlock to protect the hash bucket linkage.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-13-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT and rely
on RCU to guarantee dev and nexthop lifetime.
Then, the RCU section will start before ip6_route_info_create_nh()
in ip6_route_multipath_add(), but ip6_route_info_create() is called
in the same loop and will sleep.
Let's split the loop into ip6_route_mpath_info_create() and
ip6_route_mpath_info_create_nh().
Note that ip6_route_info_append() is now integrated into
ip6_route_mpath_info_create_nh() because we need to call different
free functions for nexthops that passed ip6_route_info_create_nh().
In case of failure, the remaining nexthops that ip6_route_info_create_nh()
has not been called for will be freed by ip6_route_mpath_info_cleanup().
OTOH, if a nexthop passes ip6_route_info_create_nh(), it will be linked
to a local temporary list, which will be spliced back to rt6_nh_list.
In case of failure, these nexthops will be released by fib6_info_release()
in ip6_route_multipath_add().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-12-kuniyu@amazon.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>
ip6_route_info_create_nh() will be called under RCU.
Then, fib6_nh_init() is also under RCU, but per-cpu memory allocation
is very likely to fail with GFP_ATOMIC while bulk-adding IPv6 routes
and we would see a bunch of this message in dmesg.
percpu: allocation failed, size=8 align=8 atomic=1, atomic alloc failed, no space left
percpu: allocation failed, size=8 align=8 atomic=1, atomic alloc failed, no space left
Let's preallocate rt->fib6_nh->rt6i_pcpu in ip6_route_info_create().
If something fails before the original memory allocation in
fib6_nh_init(), ip6_route_info_create_nh() calls fib6_info_release(),
which releases the preallocated per-cpu memory.
Note that rt->fib6_nh->rt6i_pcpu is not preallocated when called via
ipv6_stub, so we still need alloc_percpu_gfp() in fib6_nh_init().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-8-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT and rely
on RCU to guarantee dev and nexthop lifetime.
Then, we want to allocate as much as possible before entering
the RCU section.
The RCU section will start in the middle of ip6_route_info_create(),
and this is problematic for ip6_route_multipath_add() that calls
ip6_route_info_create() multiple times.
Let's split ip6_route_info_create() into two parts; one for memory
allocation and another for nexthop setup.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-7-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT.
Then, we must perform two lookups for nexthop and dev under RCU
to guarantee their lifetime.
ip6_route_info_create() calls nexthop_find_by_id() first if
RTA_NH_ID is specified, and then allocates struct fib6_info.
nexthop_find_by_id() must be called under RCU, but we do not want
to use GFP_ATOMIC for memory allocation here, which will be likely
to fail in ip6_route_multipath_add().
Let's move nexthop_find_by_id() after the memory allocation so
that we can later split ip6_route_info_create() into two parts:
the sleepable part and the RCU part.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-6-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In ip6_route_multipath_add(), we call rt6_qualify_for_ecmp() for each
entry. If it returns false, the request fails.
rt6_qualify_for_ecmp() returns false if either of the conditions below
is true:
1. f6i->fib6_flags has RTF_ADDRCONF
2. f6i->nh is not NULL
3. f6i->fib6_nh->fib_nh_gw_family is AF_UNSPEC
1 is unnecessary because rtm_to_fib6_config() never sets RTF_ADDRCONF
to cfg->fc_flags.
2. is equivalent with cfg->fc_nh_id.
3. can be replaced by checking RTF_GATEWAY in the base and each multipath
entry because AF_INET6 is set to f6i->fib6_nh->fib_nh_gw_family only when
cfg.fc_is_fdb is true or RTF_GATEWAY is set, but the former is always
false.
These checks do not require RCU and can be done earlier.
Let's perform the equivalent checks in rtm_to_fib6_multipath_config().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-5-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ip6_route_info_create() is called from 3 functions:
* ip6_route_add()
* ip6_route_multipath_add()
* addrconf_f6i_alloc()
addrconf_f6i_alloc() does not need validation for struct fib6_config in
ip6_route_info_create().
ip6_route_multipath_add() calls ip6_route_info_create() for multiple
routes with slightly different fib6_config instances, which is copied
from the base config passed from userspace. So, we need not validate
the same config repeatedly.
Let's move such validation into rtm_to_fib6_config().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-4-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Basically, removing an IPv6 route does not require RTNL because
the IPv6 routing tables are protected by per table lock.
inet6_rtm_delroute() calls nexthop_find_by_id() to check if the
nexthop specified by RTA_NH_ID exists. nexthop uses rbtree and
the top-down walk can be safely performed under RCU.
ip6_route_del() already relies on RCU and the table lock, but we
need to extend the RCU critical section a bit more to cover
__ip6_del_rt(). For example, nexthop_for_each_fib6_nh() and
inet6_rt_notify() needs RCU.
Let's call nexthop_find_by_id() and __ip6_del_rt() under RCU and
get rid of RTNL from inet6_rtm_delroute() and SIOCDELRT.
Even if the nexthop is removed after rcu_read_unlock() in
inet6_rtm_delroute(), __remove_nexthop_fib() cleans up the routes
tied to the nexthop, and ip6_route_del() returns -ESRCH. So the
request was at least valid as of nexthop_find_by_id(), and it's just
a matter of timing.
Note that we need to pass false to lwtunnel_valid_encap_type_attr().
The following patches also use the newroute bool.
Note also that fib6_get_table() does not require RCU because once
allocated fib6_table is not freed until netns dismantle. I will
post a follow-up series to convert such callers to RCU-lockless
version. [0]
Link: https://lore.kernel.org/netdev/20250417174557.65721-1-kuniyu@amazon.com/ #[0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-3-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We will perform RTM_NEWROUTE and RTM_DELROUTE under RCU, and then
we want to perform some validation out of the RCU scope.
When creating / removing an IPv6 route with RTA_MULTIPATH,
inet6_rtm_newroute() / inet6_rtm_delroute() validates RTA_GATEWAY
in each multipath entry.
Let's do that in rtm_to_fib6_config().
Note that now RTM_DELROUTE returns an error for RTA_MULTIPATH with
0 entries, which was accepted but should result in -EINVAL as
RTM_NEWROUTE.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418000443.43734-2-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If the dst_entry is the same post transformation (which is a valid use
case for IOAM), we don't add it to the cache to avoid a reference loop.
Instead, we use a "fake" dst_entry and add it to the cache as a signal.
When we read the cache, we compare it with our "fake" dst_entry and
therefore detect if we're in the special case.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250415112554.23823-3-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
With this change ovpn is allowed to communicate to peers also via TCP.
Parsing of incoming messages is implemented through the strparser API.
Note that ovpn redefines sk_prot and sk_socket->ops for the TCP socket
used to communicate with the peer.
For this reason it needs to access inet6_stream_ops, which is declared
as extern in the IPv6 module, but it is not fully exported.
Therefore this patch is also adding EXPORT_SYMBOL_GPL(inet6_stream_ops)
to net/ipv6/af_inet6.c.
Cc: David Ahern <dsahern@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
Link: https://patch.msgid.link/20250415-b4-ovpn-v26-11-577f6097b964@openvpn.net
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
DCCP was orphaned in 2021 by commit 054c4610bd ("MAINTAINERS: dccp:
move Gerrit Renker to CREDITS"), which noted that the last maintainer
had been inactive for five years.
In recent years, it has become a playground for syzbot, and most changes
to DCCP have been odd bug fixes triggered by syzbot. Apart from that,
the only changes have been driven by treewide or networking API updates
or adjustments related to TCP.
Thus, in 2023, we announced we would remove DCCP in 2025 via commit
b144fcaf46 ("dccp: Print deprecation notice.").
Since then, only one individual has contacted the netdev mailing list. [0]
There is ongoing research for Multipath DCCP. The repository is hosted
on GitHub [1], and development is not taking place through the upstream
community. While the repository is published under the GPLv2 license,
the scheduling part remains proprietary, with a LICENSE file [2] stating:
"This is not Open Source software."
The researcher mentioned a plan to address the licensing issue, upstream
the patches, and step up as a maintainer, but there has been no further
communication since then.
Maintaining DCCP for a decade without any real users has become a burden.
Therefore, it's time to remove it.
Removing DCCP will also provide significant benefits to TCP. It allows
us to freely reorganize the layout of struct inet_connection_sock, which
is currently shared with DCCP, and optimize it to reduce the number of
cachelines accessed in the TCP fast path.
Note that we keep DCCP netfilter modules as requested. [3]
Link: https://lore.kernel.org/netdev/20230710182253.81446-1-kuniyu@amazon.com/T/#u #[0]
Link: https://github.com/telekom/mp-dccp #[1]
Link: https://github.com/telekom/mp-dccp/blob/mpdccp_v03_k5.10/net/dccp/non_gpl_scheduler/LICENSE #[2]
Link: https://lore.kernel.org/netdev/Z_VQ0KlCRkqYWXa-@calendula/ #[3]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM and SELinux)
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Link: https://patch.msgid.link/20250410023921.11307-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 5eb902b8e7 ("net/ipv6: Remove expired routes with a separated list
of routes.") introduced a separated list for managing route expiration via
the GC timer.
However, it missed adding exception routes (created by ip6_rt_update_pmtu()
and rt6_do_redirect()) to this GC list. As a result, these exceptions were
never considered for expiration and removal, leading to stale entries
persisting in the routing table.
This patch fixes the issue by calling fib6_add_gc_list() in
rt6_insert_exception(), ensuring that exception routes are properly tracked
and garbage collected when expired.
Fixes: 5eb902b8e7 ("net/ipv6: Remove expired routes with a separated list of routes.")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/837e7506ffb63f47faa2b05d9b85481aad28e1a4.1744134377.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Devices in the networking path, such as firewalls, NATs, or routers, which
can perform SNAT or DNAT, use addresses from their own limited address
pools to masquerade the source address during forwarding, causing PAWS
verification to fail more easily.
Currently, packet loss statistics for PAWS can only be viewed through MIB,
which is a global metric and cannot be precisely obtained through tracing
to get the specific 4-tuple of the dropped packet. In the past, we had to
use kprobe ret to retrieve relevant skb information from
tcp_timewait_state_process().
We add a drop_reason pointer, similar to what previous commit does:
commit e34100c2ec ("tcp: add a drop_reason pointer to tcp_check_req()")
This commit addresses the PAWSESTABREJECTED case and also sets the
corresponding drop reason.
We use 'pwru' to test.
Before this commit:
''''
./pwru 'port 9999'
2025/04/07 13:40:19 Listening for events..
TUPLE FUNC
172.31.75.115:12345->172.31.75.114:9999(tcp) sk_skb_reason_drop(SKB_DROP_REASON_NOT_SPECIFIED)
'''
After this commit:
'''
./pwru 'port 9999'
2025/04/07 13:51:34 Listening for events..
TUPLE FUNC
172.31.75.115:12345->172.31.75.114:9999(tcp) sk_skb_reason_drop(SKB_DROP_REASON_TCP_RFC7323_TW_PAWS)
'''
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250409112614.16153-2-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull networking fixes from Paolo Abeni:
"Including fixes from netfilter.
Current release - regressions:
- core: hold instance lock during NETDEV_CHANGE
- rtnetlink: fix bad unlock balance in do_setlink()
- ipv6:
- fix null-ptr-deref in addrconf_add_ifaddr()
- align behavior across nexthops during path selection
Previous releases - regressions:
- sctp: prevent transport UaF in sendmsg
- mptcp: only inc MPJoinAckHMacFailure for HMAC failures
Previous releases - always broken:
- sched:
- make ->qlen_notify() idempotent
- ensure sufficient space when sending filter netlink notifications
- sch_sfq: really don't allow 1 packet limit
- netfilter: fix incorrect avx2 match of 5th field octet
- tls: explicitly disallow disconnect
- eth: octeontx2-pf: fix VF root node parent queue priority"
* tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (38 commits)
ethtool: cmis_cdb: Fix incorrect read / write length extension
selftests: netfilter: add test case for recent mismatch bug
nft_set_pipapo: fix incorrect avx2 match of 5th field octet
net: ppp: Add bound checking for skb data on ppp_sync_txmung
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
ipv6: Align behavior across nexthops during path selection
net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY
net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend()
selftests/tc-testing: sfq: check that a derived limit of 1 is rejected
net_sched: sch_sfq: move the limit validation
net_sched: sch_sfq: use a temporary work area for validating configuration
net: libwx: handle page_pool_dev_alloc_pages error
selftests: mptcp: validate MPJoin HMacFailure counters
mptcp: only inc MPJoinAckHMacFailure for HMAC failures
rtnetlink: Fix bad unlock balance in do_setlink().
net: ethtool: Don't call .cleanup_data when prepare_data fails
tc: Ensure we have enough buffer space when sending filter netlink notifications
net: libwx: Fix the wrong Rx descriptor field
octeontx2-pf: qos: fix VF root node parent queue index
selftests: tls: check that disconnect does nothing
...
A nexthop is only chosen when the calculated multipath hash falls in the
nexthop's hash region (i.e., the hash is smaller than the nexthop's hash
threshold) and when the nexthop is assigned a non-negative score by
rt6_score_route().
Commit 4d0ab3a688 ("ipv6: Start path selection from the first
nexthop") introduced an unintentional difference between the first
nexthop and the rest when the score is negative.
When the first nexthop matches, but has a negative score, the code will
currently evaluate subsequent nexthops until one is found with a
non-negative score. On the other hand, when a different nexthop matches,
but has a negative score, the code will fallback to the nexthop with
which the selection started ('match').
Align the behavior across all nexthops and fallback to 'match' when the
first nexthop matches, but has a negative score.
Fixes: 3d709f69a3 ("ipv6: Use hash-threshold instead of modulo-N")
Fixes: 4d0ab3a688 ("ipv6: Start path selection from the first nexthop")
Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Closes: https://lore.kernel.org/netdev/67efef607bc41_1ddca82948c@willemb.c.googlers.com.notmuch/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250408084316.243559-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Most UDP tunnels bind a socket to a local port, with ANY address, no
peer and no interface index specified.
Additionally it's quite common to have a single tunnel device per
namespace.
Track in each namespace the UDP tunnel socket respecting the above.
When only a single one is present, store a reference in the netns.
When such reference is not NULL, UDP tunnel GRO lookup just need to
match the incoming packet destination port vs the socket local port.
The tunnel socket never sets the reuse[port] flag[s]. When bound to no
address and interface, no other socket can exist in the same netns
matching the specified local port.
Matching packets with non-local destination addresses will be
aggregated, and eventually segmented as needed - no behavior changes
intended.
Restrict the optimization to kernel sockets only: it covers all the
relevant use-cases, and user-space owned sockets could be disconnected
and rebound after setup_udp_tunnel_sock(), breaking the uniqueness
assumption
Note that the UDP tunnel socket reference is stored into struct
netns_ipv4 for both IPv4 and IPv6 tunnels. That is intentional to keep
all the fastpath-related netns fields in the same struct and allow
cacheline-based optimization. Currently both the IPv4 and IPv6 socket
pointer share the same cacheline as the `udp_table` field.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/41d16bc8d1257d567f9344c445b4ae0b4a91ede4.1744040675.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Nexthops whose link is down are not supposed to be considered during
path selection when the "ignore_routes_with_linkdown" sysctl is set.
This is done by assigning them a negative region boundary.
However, when comparing the computed hash (unsigned) with the region
boundary (signed), the negative region boundary is treated as unsigned,
resulting in incorrect nexthop selection.
Fix by treating the computed hash as signed. Note that the computed hash
is always in range of [0, 2^31 - 1].
Fixes: 3d709f69a3 ("ipv6: Use hash-threshold instead of modulo-N")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250402114224.293392-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cited commit transitioned IPv6 path selection to use hash-threshold
instead of modulo-N. With hash-threshold, each nexthop is assigned a
region boundary in the multipath hash function's output space and a
nexthop is chosen if the calculated hash is smaller than the nexthop's
region boundary.
Hash-threshold does not work correctly if path selection does not start
with the first nexthop. For example, if fib6_select_path() is always
passed the last nexthop in the group, then it will always be chosen
because its region boundary covers the entire hash function's output
space.
Fix this by starting the selection process from the first nexthop and do
not consider nexthops for which rt6_score_route() provided a negative
score.
Fixes: 3d709f69a3 ("ipv6: Use hash-threshold instead of modulo-N")
Reported-by: Stanislav Fomichev <stfomichev@gmail.com>
Closes: https://lore.kernel.org/netdev/Z9RIyKZDNoka53EO@mini-arch/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250402114224.293392-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipv6_add_dev might call dev_disable_lro which unconditionally grabs
instance lock, so it will deadlock during NETDEV_REGISTER. Switch
to netif_disable_lro.
Make sure all callers hold the instance lock as well.
Cc: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-4-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Using RTEXT_FILTER_SKIP_STATS is incorrectly skipping non-stats IPv6
netlink attributes on link dump. This causes issues on userspace tools,
e.g iproute2 is not rendering address generation mode as it should due
to missing netlink attribute.
Move the filling of IFLA_INET6_STATS and IFLA_INET6_ICMP6STATS to a
helper function guarded by a flag check to avoid hitting the same
situation in the future.
Fixes: d5566fd72e ("rtnetlink: RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats")
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250402121751.3108-1-ffmancera@riseup.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When calling netlbl_conn_setattr(), addr->sa_family is used
to determine the function behavior. If sk is an IPv4 socket,
but the connect function is called with an IPv6 address,
the function calipso_sock_setattr() is triggered.
Inside this function, the following code is executed:
sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
Since sk is an IPv4 socket, pinet6 is NULL, leading to a
null pointer dereference.
This patch fixes the issue by checking if inet6_sk(sk)
returns a NULL pointer before accessing pinet6.
Signed-off-by: Debin Zhu <mowenroot@163.com>
Signed-off-by: Bitao Ouyang <1985755126@qq.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Fixes: ceba1832b1 ("calipso: Set the calipso socket label to match the secattr.")
Link: https://patch.msgid.link/20250401124018.4763-1-mowenroot@163.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>