Pablo Neira Ayuso says:
====================
Netfilter fixes for net
v2: with kdoc fixes per Paolo Abeni.
The following patchset contains Netfilter fixes for net:
Patch #1 and #2 handle an esoteric scenario: Given two tasks sending UDP
packets to one another, two packets of the same flow in each direction
handled by different CPUs that result in two conntrack objects in NEW
state, where reply packet loses race. Then, patch #3 adds a testcase for
this scenario. Series from Florian Westphal.
1) NAT engine can falsely detect a port collision if it happens to pick
up a reply packet as NEW rather than ESTABLISHED. Add extra code to
detect this and suppress port reallocation in this case.
2) To complete the clash resolution in the reply direction, extend conntrack
logic to detect clashing conntrack in the reply direction to existing entry.
3) Adds a test case.
Then, an assorted list of fixes follow:
4) Add a selftest for tproxy, from Antonio Ojea.
5) Guard ctnetlink_*_size() functions under
#if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
From Andy Shevchenko.
6) Use -m socket --transparent in iptables tproxy documentation.
From XIE Zhibang.
7) Call kfree_rcu() when releasing flowtable hooks to address race with
netlink dump path, from Phil Sutter.
8) Fix compilation warning in nf_reject with CONFIG_BRIDGE_NETFILTER=n.
From Simon Horman.
9) Guard ctnetlink_label_size() under CONFIG_NF_CONNTRACK_EVENTS which
is its only user, to address a compilation warning. From Simon Horman.
10) Use rcu-protected list iteration over basechain hooks from netlink
dump path.
11) Fix memcg for nf_tables, use GFP_KERNEL_ACCOUNT is not complete.
12) Remove old nfqueue conntrack clash resolution. Instead trying to
use same destination address consistently which requires double DNAT,
use the existing clash resolution which allows clashing packets
go through with different destination. Antonio Ojea originally
reported an issue from the postrouting chain, I proposed a fix:
https://lore.kernel.org/netfilter-devel/ZuwSwAqKgCB2a51-@calendula/T/
which he reported it did not work for him.
13) Adds a selftest for patch 12.
14) Fixes ipvs.sh selftest.
netfilter pull request 24-09-26
* tag 'nf-24-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
selftests: netfilter: Avoid hanging ipvs.sh
kselftest: add test for nfqueue induced conntrack race
netfilter: nfnetlink_queue: remove old clash resolution logic
netfilter: nf_tables: missing objects with no memcg accounting
netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path
netfilter: ctnetlink: compile ctnetlink_label_size with CONFIG_NF_CONNTRACK_EVENTS
netfilter: nf_reject: Fix build warning when CONFIG_BRIDGE_NETFILTER=n
netfilter: nf_tables: Keep deleted flowtable hooks until after RCU
docs: tproxy: ignore non-transparent sockets in iptables
netfilter: ctnetlink: Guard possible unused functions
selftests: netfilter: nft_tproxy.sh: add tcp tests
selftests: netfilter: add reverse-clash resolution test case
netfilter: conntrack: add clash resolution for reverse collisions
netfilter: nf_nat: don't try nat source port reallocation for reverse dir clash
====================
Link: https://patch.msgid.link/20240926110717.102194-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
For historical reasons there are two clash resolution spots in
netfilter, one in nfnetlink_queue and one in conntrack core.
nfnetlink_queue one was added first: If a colliding entry is found, NAT
NAT transformation is reversed by calling nat engine again with altered
tuple.
See commit 368982cd7d ("netfilter: nfnetlink_queue: resolve clash for
unconfirmed conntracks") for details.
One problem is that nf_reroute() won't take an action if the queueing
doesn't occur in the OUTPUT hook, i.e. when queueing in forward or
postrouting, packet will be sent via the wrong path.
Another problem is that the scenario addressed (2nd UDP packet sent with
identical addresses while first packet is still being processed) can also
occur without any nfqueue involvement due to threaded resolvers doing
A and AAAA requests back-to-back.
This lead us to add clash resolution logic to the conntrack core, see
commit 6a757c07e5 ("netfilter: conntrack: allow insertion of clashing
entries"). Instead of fixing the nfqueue based logic, lets remove it
and let conntrack core handle this instead.
Retain the ->update hook for sake of nfqueue based conntrack helpers.
We could axe this hook completely but we'd have to split confirm and
helper logic again, see commit ee04805ff5 ("netfilter: conntrack: make
conntrack userspace helpers work again").
This SHOULD NOT be backported to kernels earlier than v5.6; they lack
adequate clash resolution handling.
Patch was originally written by Pablo Neira Ayuso.
Reported-by: Antonio Ojea <aojea@google.com>
Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1766
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Antonio Ojea <aojea@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Several ruleset objects are still not using GFP_KERNEL_ACCOUNT for
memory accounting, update them. This includes:
- catchall elements
- compat match large info area
- log prefix
- meta secctx
- numgen counters
- pipapo set backend datastructure
- tunnel private objects
Fixes: 33758c8914 ("memcg: enable accounting for nft objects")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Lockless iteration over hook list is possible from netlink dump path,
use rcu variant to iterate over the hook list as is done with flowtable
hooks.
Fixes: b9703ed44f ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Only provide ctnetlink_label_size when it is used,
which is when CONFIG_NF_CONNTRACK_EVENTS is configured.
Flagged by clang-18 W=1 builds as:
.../nf_conntrack_netlink.c:385:19: warning: unused function 'ctnetlink_label_size' [-Wunused-function]
385 | static inline int ctnetlink_label_size(const struct nf_conn *ct)
| ^~~~~~~~~~~~~~~~~~~~
The condition on CONFIG_NF_CONNTRACK_LABELS being removed by
this patch guards compilation of non-trivial implementations
of ctnetlink_dump_labels() and ctnetlink_label_size().
However, this is not necessary as each of these functions
will always return 0 if CONFIG_NF_CONNTRACK_LABELS is not defined
as each function starts with the equivalent of:
struct nf_conn_labels *labels = nf_ct_labels_find(ct);
if (!labels)
return 0;
And nf_ct_labels_find always returns NULL if CONFIG_NF_CONNTRACK_LABELS
is not enabled. So I believe that the compiler optimises the code away
in such cases anyway.
Found by inspection.
Compile tested only.
Originally splitted in two patches, Pablo Neira Ayuso collapsed them and
added Fixes: tag.
Fixes: 0ceabd8387 ("netfilter: ctnetlink: deliver labels to userspace")
Link: https://lore.kernel.org/netfilter-devel/20240909151712.GZ2097826@kernel.org/
Signed-off-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If CONFIG_BRIDGE_NETFILTER is not enabled, which is the case for x86_64
defconfig, then building nf_reject_ipv4.c and nf_reject_ipv6.c with W=1
using gcc-14 results in the following warnings, which are treated as
errors:
net/ipv4/netfilter/nf_reject_ipv4.c: In function 'nf_send_reset':
net/ipv4/netfilter/nf_reject_ipv4.c:243:23: error: variable 'niph' set but not used [-Werror=unused-but-set-variable]
243 | struct iphdr *niph;
| ^~~~
cc1: all warnings being treated as errors
net/ipv6/netfilter/nf_reject_ipv6.c: In function 'nf_send_reset6':
net/ipv6/netfilter/nf_reject_ipv6.c:286:25: error: variable 'ip6h' set but not used [-Werror=unused-but-set-variable]
286 | struct ipv6hdr *ip6h;
| ^~~~
cc1: all warnings being treated as errors
Address this by reducing the scope of these local variables to where
they are used, which is code only compiled when CONFIG_BRIDGE_NETFILTER
enabled.
Compile tested and run through netfilter selftests.
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Closes: https://lore.kernel.org/netfilter-devel/20240906145513.567781-1-andriy.shevchenko@linux.intel.com/
Signed-off-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Documentation of list_del_rcu() warns callers to not immediately free
the deleted list item. While it seems not necessary to use the
RCU-variant of list_del() here in the first place, doing so seems to
require calling kfree_rcu() on the deleted item as well.
Fixes: 3f0465a9ef ("netfilter: nf_tables: dynamically allocate hooks per net_device in flowtables")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Some of the functions may be unused (CONFIG_NETFILTER_NETLINK_GLUE_CT=n
and CONFIG_NF_CONNTRACK_EVENTS=n), it prevents kernel builds with clang,
`make W=1` and CONFIG_WERROR=y:
net/netfilter/nf_conntrack_netlink.c:657:22: error: unused function 'ctnetlink_acct_size' [-Werror,-Wunused-function]
657 | static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
| ^~~~~~~~~~~~~~~~~~~
net/netfilter/nf_conntrack_netlink.c:667:19: error: unused function 'ctnetlink_secctx_size' [-Werror,-Wunused-function]
667 | static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
| ^~~~~~~~~~~~~~~~~~~~~
net/netfilter/nf_conntrack_netlink.c:683:22: error: unused function 'ctnetlink_timestamp_size' [-Werror,-Wunused-function]
683 | static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
| ^~~~~~~~~~~~~~~~~~~~~~~~
Fix this by guarding possible unused functions with ifdeffery.
See also commit 6863f5643d ("kbuild: allow Clang to find unused static
inline functions for W=1 build").
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Given existing entry:
ORIGIN: a:b -> c:d
REPLY: c:d -> a:b
And colliding entry:
ORIGIN: c:d -> a:b
REPLY: a:b -> c:d
The colliding ct (and the associated skb) get dropped on insert.
Permit this by checking if the colliding entry matches the reply
direction.
Happens when both ends send packets at same time, both requests are picked
up as NEW, rather than NEW for the 'first' and 'ESTABLISHED' for the
second packet.
This is an esoteric condition, as ruleset must permit NEW connections
in either direction and both peers must already have a bidirectional
traffic flow at the time conntrack gets enabled.
Allow the 'reverse' skb to pass and assign the existing (clashing)
entry.
While at it, also drop the extra 'dying' check, this is already
tested earlier by the calling function.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
A conntrack entry can be inserted to the connection tracking table if there
is no existing entry with an identical tuple in either direction.
Example:
INITIATOR -> NAT/PAT -> RESPONDER
Initiator passes through NAT/PAT ("us") and SNAT is done (saddr rewrite).
Then, later, NAT/PAT machine itself also wants to connect to RESPONDER.
This will not work if the SNAT done earlier has same IP:PORT source pair.
Conntrack table has:
ORIGINAL: $IP_INITATOR:$SPORT -> $IP_RESPONDER:$DPORT
REPLY: $IP_RESPONDER:$DPORT -> $IP_NAT:$SPORT
and new locally originating connection wants:
ORIGINAL: $IP_NAT:$SPORT -> $IP_RESPONDER:$DPORT
REPLY: $IP_RESPONDER:$DPORT -> $IP_NAT:$SPORT
This is handled by the NAT engine which will do a source port reallocation
for the locally originating connection that is colliding with an existing
tuple by attempting a source port rewrite.
This is done even if this new connection attempt did not go through a
masquerade/snat rule.
There is a rare race condition with connection-less protocols like UDP,
where we do the port reallocation even though its not needed.
This happens when new packets from the same, pre-existing flow are received
in both directions at the exact same time on different CPUs after the
conntrack table was flushed (or conntrack becomes active for first time).
With strict ordering/single cpu, the first packet creates new ct entry and
second packet is resolved as established reply packet.
With parallel processing, both packets are picked up as new and both get
their own ct entry.
In this case, the 'reply' packet (picked up as ORIGINAL) can be mangled by
NAT engine because a port collision is detected.
This change isn't enough to prevent a packet drop later during
nf_conntrack_confirm(), the existing clash resolution strategy will not
detect such reverse clash case. This is resolved by a followup patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When broadcasting data to multiple nodes via MHI, using skb_clone()
causes all nodes to receive the same header data. This can result in
packets being discarded by endpoints, leading to lost data.
This issue occurs when a socket is closed, and a QRTR_TYPE_DEL_CLIENT
packet is broadcasted. All nodes receive the same destination node ID,
causing the node connected to the client to discard the packet and
remain unaware of the client's deletion.
Replace skb_clone() with pskb_copy(), to create a separate copy of
the header for each sk_buff.
Fixes: bdabad3e36 ("net: Add Qualcomm IPC router")
Signed-off-by: Youssef Samir <quic_yabdulra@quicinc.com>
Reviewed-by: Jeffery Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Carl Vanderlip <quic_carlv@quicinc.com>
Reviewed-by: Chris Lew <quic_clew@quicinc.com>
Link: https://patch.msgid.link/20240916170858.2382247-1-quic_yabdulra@quicinc.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The rpl sr tunnel code contains calls to dst_cache_*() which are
only present when the dst cache is built.
Select DST_CACHE to build the dst cache, similar to other kconfig
options in the same file.
Compiling the rpl sr tunnel without DST_CACHE will lead to linker
errors.
Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Simon Horman <horms@kernel.org> # build-tested
Signed-off-by: David S. Miller <davem@davemloft.net>
Marc Kleine-Budde says:
====================
pull-request: can 2024-09-12
Kuniyuki Iwashima's patch fixes an incomplete bug fix in the CAN BCM
protocol, which was introduced during v6.11.
A patch by Stefan Mätje removes the unsupported CAN_CTRLMODE_3_SAMPLES
mode for CAN-USB/3-FD devices in the esd_usb driver.
The next patch is by Martin Jocic and enables 64-bit DMA addressing
for the kvaser_pciefd driver.
The last two patches both affect the m_can driver. Jake Hamby's patch
activates NAPI before interrupts are activated, a patch by me moves
the stopping of the clock after the device has been shut down.
* tag 'linux-can-fixes-for-6.11-20240912' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
can: m_can: m_can_close(): stop clocks after device has been shut down
can: m_can: enable NAPI before enabling interrupts
can: kvaser_pciefd: Enable 64-bit DMA addressing
can: esd_usb: Remove CAN_CTRLMODE_3_SAMPLES for CAN-USB/3-FD
can: bcm: Clear bo->bcm_proc_read after remove_proc_entry().
====================
Link: https://patch.msgid.link/20240912075804.2825408-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Now that both IPv4 and IPv6 support the new DSCP selector, enable user
space to configure FIB rules that make use of it by changing the policy
of the new DSCP attribute so that it accepts values in the range of [0,
63].
Use NLA_U8 rather than NLA_UINT as the field is of fixed size.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240911093748.3662015-5-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Implement support for the new DSCP selector that allows IPv6 FIB rules
to match on the entire DSCP field. This is done despite the fact that
the above can be achieved using the existing TOS selector, so that user
space program will be able to work with IPv4 and IPv6 rules in the same
way.
Differentiate between both selectors by adding a new bit in the IPv6 FIB
rule structure that is only set when the 'FRA_DSCP' attribute is
specified by user space. Reject rules that use both selectors.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240911093748.3662015-4-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Implement support for the new DSCP selector that allows IPv4 FIB rules
to match on the entire DSCP field, unlike the existing TOS selector that
only matches on the three lower DSCP bits.
Differentiate between both selectors by adding a new bit in the IPv4 FIB
rule structure (in an existing one byte hole) that is only set when the
'FRA_DSCP' attribute is specified by user space. Reject rules that use
both selectors.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240911093748.3662015-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The FIB rule TOS selector is implemented differently between IPv4 and
IPv6. In IPv4 it is used to match on the three "Type of Services" bits
specified in RFC 791, while in IPv6 is it is used to match on the six
DSCP bits specified in RFC 2474.
Add a new FIB rule attribute to allow matching on DSCP. The attribute
will be used to implement a 'dscp' selector in ip-rule with a consistent
behavior between IPv4 and IPv6.
For now, set the type of the attribute to 'NLA_REJECT' so that user
space will not be able to configure it. This restriction will be lifted
once both IPv4 and IPv6 support the new attribute.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240911093748.3662015-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
During the firmware flashing process, notifications are sent to user
space to provide progress updates. When an error occurs, an error
message is sent to indicate what went wrong.
In some cases, appropriate error messages are missing.
Add relevant error messages where applicable, allowing user space to better
understand the issues encountered.
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240910091044.3044568-1-danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Clang static checker (scan-build) warning:
net/tipc/bcast.c:305:4:
The expression is an uninitialized value. The computed value will also
be garbage [core.uninitialized.Assign]
305 | (*cong_link_cnt)++;
| ^~~~~~~~~~~~~~~~~~
tipc_rcast_xmit() will increase cong_link_cnt's value, but cong_link_cnt
is uninitialized. Although it won't really cause a problem, it's better
to fix it.
Fixes: dca4a17d24 ("tipc: fix potential hanging after b/rcast changing")
Signed-off-by: Su Hui <suhui@nfschina.com>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Link: https://patch.msgid.link/20240912110119.2025503-1-suhui@nfschina.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
