It is currently impossible to enable ipv6 forwarding on a per-interface
basis like in ipv4. To enable forwarding on an ipv6 interface we need to
enable it on all interfaces and disable it on the other interfaces using
a netfilter rule. This is especially cumbersome if you have lots of
interfaces and only want to enable forwarding on a few. According to the
sysctl docs [0] the `net.ipv6.conf.all.forwarding` enables forwarding
for all interfaces, while the interface-specific
`net.ipv6.conf.<interface>.forwarding` configures the interface
Host/Router configuration.
Introduce a new sysctl flag `force_forwarding`, which can be set on every
interface. The ip6_forwarding function will then check if the global
forwarding flag OR the force_forwarding flag is active and forward the
packet.
To preserve backwards-compatibility reset the flag (on all interfaces)
to 0 if the net.ipv6.conf.all.forwarding flag is set to 0.
Add a short selftest that checks if a packet gets forwarded with and
without `force_forwarding`.
[0]: https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Gabriel Goller <g.goller@proxmox.com>
Link: https://patch.msgid.link/20250722081847.132632-1-g.goller@proxmox.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pneigh_lookup() has ASSERT_RTNL() in the middle of the function, which
is confusing.
When called with the last argument, creat, 0, pneigh_lookup() literally
looks up a proxy neighbour entry. This is the case of the reader path
as the fast path and RTM_GETNEIGH.
pneigh_lookup(), however, creates a pneigh_entry when called with creat 1
from RTM_NEWNEIGH and SIOCSARP, which require RTNL.
Let's split pneigh_lookup() into two functions.
We will convert all the reader paths to RCU, and read_lock_bh(&tbl->lock)
in the new pneigh_lookup() will be dropped.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250716221221.442239-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since its introduction in commit 2e910b9532 ("net: Add a function to
splice pages into an skbuff for MSG_SPLICE_PAGES"), skb_splice_from_iter()
never used the @gfp argument. Remove it and adapt callers.
No functional change intended.
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250702-splice-drop-unused-v3-2-55f68b60d2b7@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the new helpers as a step to deal with potential dst->dev races.
v2: fix typo in ipv6_rthdr_rcv() (kernel test robot <lkp@intel.com>)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-10-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the new helper as a step to deal with potential dst->dev races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
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>
When spanning datagram construction over multiple send calls using
MSG_MORE, per datagram settings are configured on the first send.
That is when ip(6)_setup_cork stores these settings for subsequent use
in __ip(6)_append_data and others.
The only flag that escaped this was dontfrag. As a result, a datagram
could be constructed with df=0 on the first sendmsg, but df=1 on a
next. Which is what cmsg_ip.sh does in an upcoming MSG_MORE test in
the "diff" scenario.
Changing datagram conditions in the middle of constructing an skb
makes this already complex code path even more convoluted. It is here
unintentional. Bring this flag in line with expected sockopt/cmsg
behavior.
And stop passing ipc6 to __ip6_append_data, to avoid such issues
in the future. This is already the case for __ip_append_data.
inet6_cork had a 6 byte hole, so the 1B flag has no impact.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250307033620.411611-3-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As of the blamed commit ipc6.dontfrag is always initialized at the
start of udpv6_sendmsg, by ipcm6_init_sk, to either 0 or 1.
Later checks against -1 are no longer needed and the branches are now
dead code.
The blamed commit had removed those branches. But I had overlooked
this one case.
UDP has both a lockless fast path and a slower path for corked
requests. This branch remained in the fast path.
Fixes: 096208592b ("ipv6: replace ipcm6_init calls with ipcm6_init_sk")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250307033620.411611-2-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
All inet_getpeer() callers except ip4_frag_init() don't need
to acquire a permanent refcount on the inetpeer.
They can switch to full RCU protection.
Move the refcount_inc_not_zero() into ip4_frag_init(),
so that all the other callers no longer have to
perform a pair of expensive atomic operations on
a possibly contended cache line.
inet_putpeer() no longer needs to be exported.
After this patch, my DUT can receive 8,400,000 UDP packets
per second targeting closed ports, using 50% less cpu cycles
than before.
Also change two calls to l3mdev_master_ifindex() by
l3mdev_master_ifindex_rcu() (Ido ideas)
Fixes: 8c2bd38b95 ("icmp: change the order of rate limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241215175629.1248773-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The Linux socket API currently allows setting SO_PRIORITY at the
socket level, applying a uniform priority to all packets sent through
that socket. The exception to this is IP_TOS, when the priority value
is calculated during the handling of
ancillary data, as implemented in commit f02db315b8 ("ipv4: IP_TOS
and IP_TTL can be specified as ancillary data").
However, this is a computed
value, and there is currently no mechanism to set a custom priority
via control messages prior to this patch.
According to this patch, if SO_PRIORITY is specified as ancillary data,
the packet is sent with the priority value set through
sockc->priority, overriding the socket-level values
set via the traditional setsockopt() method. This is analogous to
the existing support for SO_MARK, as implemented in
commit c6af0c227a ("ip: support SO_MARK cmsg").
If both cmsg SO_PRIORITY and IP_TOS are passed, then the one that
takes precedence is the last one in the cmsg list.
This patch has the side effect that raw_send_hdrinc now interprets cmsg
IP_TOS.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Suggested-by: Ferenc Fejes <fejes@inf.elte.hu>
Signed-off-by: Anna Emese Nyiri <annaemesenyiri@gmail.com>
Link: https://patch.msgid.link/20241213084457.45120-3-annaemesenyiri@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
UDP send path suffers from one indirect call to ip_generic_getfrag()
We can use INDIRECT_CALL_1() to avoid it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Brian Vazquez <brianvv@google.com>
Link: https://patch.msgid.link/20241203173617.2595451-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The last type of sockets which supports SOF_TIMESTAMPING_OPT_ID is RAW
sockets. To add new option this patch converts all callers (direct and
indirect) of _sock_tx_timestamp to provide sockcm_cookie instead of
tsflags. And while here fix __sock_tx_timestamp to receive tsflags as
__u32 instead of __u16.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Link: https://patch.msgid.link/20241001125716.2832769-3-vadfed@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX
timestamps and packets sent via socket. Unfortunately, there is no way
to reliably predict socket timestamp ID value in case of error returned
by sendmsg. For UDP sockets it's impossible because of lockless
nature of UDP transmit, several threads may send packets in parallel. In
case of RAW sockets MSG_MORE option makes things complicated. More
details are in the conversation [1].
This patch adds new control message type to give user-space
software an opportunity to control the mapping between packets and
values by providing ID with each sendmsg for UDP sockets.
The documentation is also added in this patch.
[1] https://lore.kernel.org/netdev/CALCETrU0jB+kg0mhV6A8mrHfTE1D1pr1SD_B9Eaa9aDPfgHdtA@mail.gmail.com/
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Link: https://patch.msgid.link/20241001125716.2832769-2-vadfed@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If skb_expand_head() returns NULL, skb has been freed
and the associated dst/idev could also have been freed.
We must use rcu_read_lock() to prevent a possible UAF.
Fixes: 0c9f227bee ("ipv6: use skb_expand_head in ip6_xmit")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vasily Averin <vasily.averin@linux.dev>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240820160859.3786976-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If skb_expand_head() returns NULL, skb has been freed
and associated dst/idev could also have been freed.
We need to hold rcu_read_lock() to make sure the dst and
associated idev are alive.
Fixes: 5796015fa9 ("ipv6: allocate enough headroom in ip6_finish_output2()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vasily Averin <vasily.averin@linux.dev>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240820160859.3786976-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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: 0d240e7811 ("net: vrf: Implement get_saddr for IPv6")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://patch.msgid.link/20240710081521.3809742-3-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tstamp_type is now set based on actual clockid_t compressed
into 2 bits.
To make the design scalable for future needs this commit bring in
the change to extend the tstamp_type:1 to tstamp_type:2 to support
other clockid_t timestamp.
We now support CLOCK_TAI as part of tstamp_type as part of this
commit with existing support CLOCK_MONOTONIC and CLOCK_REALTIME.
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240509211834.3235191-3-quic_abchauha@quicinc.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
mono_delivery_time was added to check if skb->tstamp has delivery
time in mono clock base (i.e. EDT) otherwise skb->tstamp has
timestamp in ingress and delivery_time at egress.
Renaming the bitfield from mono_delivery_time to tstamp_type is for
extensibilty for other timestamps such as userspace timestamp
(i.e. SO_TXTIME) set via sock opts.
As we are renaming the mono_delivery_time to tstamp_type, it makes
sense to start assigning tstamp_type based on enum defined
in this commit.
Earlier we used bool arg flag to check if the tstamp is mono in
function skb_set_delivery_time, Now the signature of the functions
accepts tstamp_type to distinguish between mono and real time.
Also skb_set_delivery_type_by_clockid is a new function which accepts
clockid to determine the tstamp_type.
In future tstamp_type:1 can be extended to support userspace timestamp
by increasing the bitfield.
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240509211834.3235191-2-quic_abchauha@quicinc.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Cross-merge networking fixes after downstream PR.
No conflicts.
Adjacent changes:
drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
35d92abfba ("net: hns3: fix kernel crash when devlink reload during initialization")
2a1a1a7b5f ("net: hns3: add command queue trace for hns3")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As it was done in commit fc1092f515 ("ipv4: Fix uninit-value access in
__ip_make_skb()") for IPv4, check FLOWI_FLAG_KNOWN_NH on fl6->flowi6_flags
instead of testing HDRINCL on the socket to avoid a race condition which
causes uninit-value access.
Fixes: ea30388bae ("ipv6: Fix an uninit variable access bug in __ip6_make_skb()")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 885c36e59f.
The patch currently broke the bpf selftest test_tc_dtime because
uapi field __sk_buff->tstamp_type depends on skb->mono_delivery_time which
does not necessarily mean mono with the original fix as the bit was re-used
for userspace timestamp as well to avoid tstamp reset in the forwarding
path. To solve this we need to keep mono_delivery_time as is and
introduce another bit called user_delivery_time and fall back to the
initial proposal of setting the user_delivery_time bit based on
sk_clockid set from userspace.
Fixes: 885c36e59f ("net: Re-use and set mono_delivery_time bit for userspace tstamp packets")
Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@linux.dev/
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bridge driver today has no support to forward the userspace timestamp
packets and ends up resetting the timestamp. ETF qdisc checks the
packet coming from userspace and encounters to be 0 thereby dropping
time sensitive packets. These changes will allow userspace timestamps
packets to be forwarded from the bridge to NIC drivers.
Setting the same bit (mono_delivery_time) to avoid dropping of
userspace tstamp packets in the forwarding path.
Existing functionality of mono_delivery_time remains unaltered here,
instead just extended with userspace tstamp support for bridge
forwarding path.
Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240301201348.2815102-1-quic_abchauha@quicinc.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
idev->cnf.disable_policy and net->ipv6.devconf_all->disable_policy
can be read locklessly. Add appropriate annotations on reads
and writes.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
devconf->proxy_ndp can be read and written locklessly,
add appropriate annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
idev->cnf.forwarding and net->ipv6.devconf_all->forwarding
might be read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
disable_ipv6 is read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
v2: do not preload net before rtnl_trylock() in
addrconf_disable_ipv6() (Jiri)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When SOF_TIMESTAMPING_OPT_ID is used to ambiguate timestamped datagrams,
the sk_tskey can become unpredictable in case of any error happened
during sendmsg(). Move increment later in the code and make decrement of
sk_tskey in error path. This solution is still racy in case of multiple
threads doing snedmsg() over the very same socket in parallel, but still
makes error path much more predictable.
Fixes: 09c2d251b7 ("net-timestamp: add key to disambiguate concurrent datagrams")
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240213110428.1681540-1-vadfed@meta.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When the ipv6 stack output a GSO packet, if its gso_size is larger than
dst MTU, then all segments would be fragmented. However, it is possible
for a GSO packet to have a trailing segment with smaller actual size
than both gso_size as well as the MTU, which leads to an "atomic
fragment". Atomic fragments are considered harmful in RFC-8021. An
Existing report from APNIC also shows that atomic fragments are more
likely to be dropped even it is equivalent to a no-op [1].
Add an extra check in the GSO slow output path. For each segment from
the original over-sized packet, if it fits with the path MTU, then avoid
generating an atomic fragment.
Link: https://www.potaroo.net/presentations/2022-03-01-ipv6-frag.pdf [1]
Fixes: b210de4f8c ("net: ipv6: Validate GSO SKB before finish IPv6 processing")
Reported-by: David Wragg <dwragg@cloudflare.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Link: https://lore.kernel.org/r/90912e3503a242dca0bc36958b11ed03a2696e5e.1698156966.git.yan@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Separate GSO and non-GSO packets handling to make the logic cleaner. For
GSO packets, frag_max_size check can be omitted because it is only
useful for packets defragmented by netfilter hooks. Both local output
and GRO logic won't produce GSO packets when defragment is needed. This
also mirrors what IPv4 side code is doing.
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/0e1d4599f858e2becff5c4fe0b5f843236bc3fe8.1698156966.git.yan@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RTAX_FEATURE_ALLFRAG was added before the first git commit:
https://www.mail-archive.com/bk-commits-head@vger.kernel.org/msg03399.html
The feature would send packets to the fragmentation path if a box
receives a PMTU value with less than 1280 byte. However, since commit
9d289715eb ("ipv6: stop sending PTB packets for MTU < 1280"), such
message would be simply discarded. The feature flag is neither supported
in iproute2 utility. In theory one can still manipulate it with direct
netlink message, but it is not ideal because it was based on obsoleted
guidance of RFC-2460 (replaced by RFC-8200).
The feature would always test false at the moment, so remove related
code or mark them as unused.
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/d78e44dcd9968a252143ffe78460446476a472a1.1698156966.git.yan@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
At the moment ip6_dst_lookup_tunnel() is used only by bareudp.
Ideally, other UDP tunnel implementations should use it, but to do so
the function needs to accept new parameters that are specific for UDP
tunnels, such as the ports.
Prepare for these changes by renaming the function to
udp_tunnel6_dst_lookup() and move it to file
net/ipv6/ip6_udp_tunnel.c.
This is similar to what already done for IPv4 in commit bf3fcbf7e7
("ipv4: rename and move ip_route_output_tunnel()").
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reproduce environment:
network with 3 VM linuxs is connected as below:
VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3
VM1: eth0 ip: 192.168.122.207 MTU 1500
VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500
VM3: eth0 ip: 192.168.123.240 MTU 1500
Reproduce:
VM1 send 1400 bytes UDP data to VM3 using tools scapy with flags=0.
scapy command:
send(IP(dst="192.168.123.240",flags=0)/UDP()/str('0'*1400),count=1,
inter=1.000000)
Result:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates
Ip: 1 64 11 0 3 4 0 0 4 7 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates
Ip: 1 64 12 0 3 5 0 0 4 8 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
"ForwDatagrams" increase from 4 to 5 and "OutRequests" also increase
from 7 to 8.
Issue description and patch:
IPSTATS_MIB_OUTPKTS("OutRequests") is counted with IPSTATS_MIB_OUTOCTETS
("OutOctets") in ip_finish_output2().
According to RFC 4293, it is "OutOctets" counted with "OutTransmits" but
not "OutRequests". "OutRequests" does not include any datagrams counted
in "ForwDatagrams".
ipSystemStatsOutOctets OBJECT-TYPE
DESCRIPTION
"The total number of octets in IP datagrams delivered to the
lower layers for transmission. Octets from datagrams
counted in ipIfStatsOutTransmits MUST be counted here.
ipSystemStatsOutRequests OBJECT-TYPE
DESCRIPTION
"The total number of IP datagrams that local IP user-
protocols (including ICMP) supplied to IP in requests for
transmission. Note that this counter does not include any
datagrams counted in ipSystemStatsOutForwDatagrams.
So do patch to define IPSTATS_MIB_OUTPKTS to "OutTransmits" and add
IPSTATS_MIB_OUTREQUESTS for "OutRequests".
Add IPSTATS_MIB_OUTREQUESTS counter in __ip_local_out() for ipv4 and add
IPSTATS_MIB_OUT counter in ip6_finish_output2() for ipv6.
Test result with patch:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 9 0 5 1 0 0 3 3 0 0 0 0 0 0 0 0 0 4
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 2976 1896 0 0 0 0 0 9 0 0 0 0
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 10 0 5 2 0 0 3 3 0 0 0 0 0 0 0 0 0 5
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 4404 3324 0 0 0 0 0 10 0 0 0 0
----------------------------------------------------------------------
"ForwDatagrams" increase from 1 to 2 and "OutRequests" is keeping 3.
"OutTransmits" increase from 4 to 5 and "OutOctets" increase 1428.
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Reviewed-by: Kun Song <Kun.Song@windriver.com>
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reproduce environment:
network with 3 VM linuxs is connected as below:
VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3
VM1: eth0 ip: 192.168.122.207 MTU 1800
VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500
VM3: eth0 ip: 192.168.123.240 MTU 1800
Reproduce:
VM1 send 1600 bytes UDP data to VM3 using tools scapy with flags='DF'.
scapy command:
send(IP(dst="192.168.123.240",flags='DF')/UDP()/str('0'*1600),count=1,
inter=1.000000)
Result:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss
Ip: 1 64 6 0 2 2 0 0 2 4 0 0 0 0 0 0 0 0 0
......
root@qemux86-64:~#
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss
Ip: 1 64 7 0 2 2 0 0 2 5 0 0 0 0 0 0 0 1 0
......
root@qemux86-64:~#
----------------------------------------------------------------------
ForwDatagrams is always keeping 2 without increment.
Issue description and patch:
ip_exceeds_mtu() in ip_forward() drops this IP datagram because skb len
(1600 sending by scapy) is over MTU(1500 in VM2) if "DF" is set.
According to RFC 4293 "3.2.3. IP Statistics Tables",
+-------+------>------+----->-----+----->-----+
| InForwDatagrams (6) | OutForwDatagrams (6) |
| V +->-+ OutFragReqds
| InNoRoutes | | (packets)
/ (local packet (3) | |
| IF is that of the address | +--> OutFragFails
| and may not be the receiving IF) | | (packets)
the IPSTATS_MIB_OUTFORWDATAGRAMS should be counted before fragment
check.
The existing implementation, instead, would incease the counter after
fragment check: ip_exceeds_mtu() in ipv4 and ip6_pkt_too_big() in ipv6.
So do patch to move IPSTATS_MIB_OUTFORWDATAGRAMS counter to ip_forward()
for ipv4 and ip6_forward() for ipv6.
Test result with patch:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss
Ip: 1 64 6 0 2 2 0 0 2 4 0 0 0 0 0 0 0 0 0
......
root@qemux86-64:~#
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss
Ip: 1 64 7 0 2 3 0 0 2 5 0 0 0 0 0 0 0 1 0
......
root@qemux86-64:~#
----------------------------------------------------------------------
ForwDatagrams is updated from 2 to 3.
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231011015137.27262-1-heng.guo@windriver.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This is a followup of 8bf43be799 ("net: annotate data-races
around sk->sk_priority").
sk->sk_priority can be read and written without holding the socket lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We have data-races while reading np->srcprefs
Switch the field to a plain byte, add READ_ONCE()
and WRITE_ONCE() annotations where needed,
and IPV6_ADDR_PREFERENCES setsockopt() can now be lockless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230918142321.1794107-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Most np->pmtudisc reads are racy.
Move this 3bit field on a full byte, add annotations
and make IPV6_MTU_DISCOVER setsockopt() lockless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reads from np->rtalert_isolate are racy.
Move this flag to inet->inet_flags to fix data-races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move np->dontfrag flag to inet->inet_flags to fix data-races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move np->autoflowlabel and np->autoflowlabel_set in inet->inet_flags,
to fix data-races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
np->frag_size can be read/written without holding socket lock.
Add missing annotations and make IPV6_MTU setsockopt() lockless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some np->hop_limit accesses are racy, when socket lock is not held.
Add missing annotations and switch to full lockless implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_tsflags can be read locklessly, add corresponding annotations.
Fixes: b9f40e21ef ("net-timestamp: move timestamp flags out of sk_flags")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit edf391ff17 ("snmp: add missing counters for RFC 4293") had
already added OutOctets for RFC 4293. In commit 2d8dbb04c6 ("snmp: fix
OutOctets counter to include forwarded datagrams"), OutOctets was
counted again, but not removed from ip_output().
According to RFC 4293 "3.2.3. IP Statistics Tables",
ipipIfStatsOutTransmits is not equal to ipIfStatsOutForwDatagrams. So
"IPSTATS_MIB_OUTOCTETS must be incremented when incrementing" is not
accurate. And IPSTATS_MIB_OUTOCTETS should be counted after fragment.
This patch reverts commit 2d8dbb04c6 ("snmp: fix OutOctets counter to
include forwarded datagrams") and move IPSTATS_MIB_OUTOCTETS to
ip_finish_output2 for ipv4.
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
