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2024-05-06netfilter: conntrack: documentation: remove reference to non-existent sysctlFlorian Westphal1-2/+2
The referenced sysctl doesn't exist anymore. Fixes: 4592ee7f525c ("netfilter: conntrack: remove offload_pickup sysctl again") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-08-16netfilter: set default timeout to 3 secs for sctp shutdown send and recv stateXin Long1-2/+2
In SCTP protocol, it is using the same timer (T2 timer) for SHUTDOWN and SHUTDOWN_ACK retransmission. However in sctp conntrack the default timeout value for SCTP_CONNTRACK_SHUTDOWN_ACK_SENT state is 3 secs while it's 300 msecs for SCTP_CONNTRACK_SHUTDOWN_SEND/RECV state. As Paolo Valerio noticed, this might cause unwanted expiration of the ct entry. In my test, with 1s tc netem delay set on the NAT path, after the SHUTDOWN is sent, the sctp ct entry enters SCTP_CONNTRACK_SHUTDOWN_SEND state. However, due to 300ms (too short) delay, when the SHUTDOWN_ACK is sent back from the peer, the sctp ct entry has expired and been deleted, and then the SHUTDOWN_ACK has to be dropped. Also, it is confusing these two sysctl options always show 0 due to all timeout values using sec as unit: net.netfilter.nf_conntrack_sctp_timeout_shutdown_recd = 0 net.netfilter.nf_conntrack_sctp_timeout_shutdown_sent = 0 This patch fixes it by also using 3 secs for sctp shutdown send and recv state in sctp conntrack, which is also RTO.initial value in SCTP protocol. Note that the very short time value for SCTP_CONNTRACK_SHUTDOWN_SEND/RECV was probably used for a rare scenario where SHUTDOWN is sent on 1st path but SHUTDOWN_ACK is replied on 2nd path, then a new connection started immediately on 1st path. So this patch also moves from SHUTDOWN_SEND/RECV to CLOSE when receiving INIT in the ORIGINAL direction. Fixes: 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.") Reported-by: Paolo Valerio <pvalerio@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Florian Westphal <fw@strlen.de>
2023-01-24netfilter: conntrack: unify established states for SCTP pathsSriram Yagnaraman1-7/+3
An SCTP endpoint can start an association through a path and tear it down over another one. That means the initial path will not see the shutdown sequence, and the conntrack entry will remain in ESTABLISHED state for 5 days. By merging the HEARTBEAT_ACKED and ESTABLISHED states into one ESTABLISHED state, there remains no difference between a primary or secondary path. The timeout for the merged ESTABLISHED state is set to 210 seconds (hb_interval * max_path_retrans + rto_max). So, even if a path doesn't see the shutdown sequence, it will expire in a reasonable amount of time. With this change in place, there is now more than one state from which we can transition to ESTABLISHED, COOKIE_ECHOED and HEARTBEAT_SENT, so handle the setting of ASSURED bit whenever a state change has happened and the new state is ESTABLISHED. Removed the check for dir==REPLY since the transition to ESTABLISHED can happen only in the reply direction. Fixes: 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.") Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-12-13netfilter: conntrack: document sctp timeoutsSriram Yagnaraman1-0/+33
Exposed through sysctl, update documentation to describe sctp states and their default timeouts. Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-09-21netfilter: conntrack: remove nf_conntrack_helper documentationPablo Neira Ayuso1-9/+0
This toggle has been already remove by b118509076b3 ("netfilter: remove nf_conntrack_helper sysctl and modparam toggles"). Remove the documentation entry for this toggle too. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de>
2022-05-13netfilter: conntrack: add nf_conntrack_events autodetect modeFlorian Westphal1-1/+4
This adds the new nf_conntrack_events=2 mode and makes it the default. This leverages the earlier flag in struct net to allow to avoid the event extension as long as no event listener is active in the namespace. This avoids, for most cases, allocation of ct->ext area. A followup patch will take further advantage of this by avoiding calls down into the event framework if the extension isn't present. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfJakub Kicinski1-5/+8
Pablo Neira Ayuso says: ==================== Netfilter fixes for net 1) Protect nft_ct template with global mutex, from Pavel Skripkin. 2) Two recent commits switched inet rt and nexthop exception hashes from jhash to siphash. If those two spots are problematic then conntrack is affected as well, so switch voer to siphash too. While at it, add a hard upper limit on chain lengths and reject insertion if this is hit. Patches from Florian Westphal. 3) Fix use-after-scope in nf_socket_ipv6 reported by KASAN, from Benjamin Hesmans. * git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf: netfilter: socket: icmp6: fix use-after-scope netfilter: refuse insertion if chain has grown too large netfilter: conntrack: switch to siphash netfilter: conntrack: sanitize table size default settings netfilter: nft_ct: protect nft_ct_pcpu_template_refcnt with mutex ==================== Link: https://lore.kernel.org/r/20210903163020.13741-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-30netfilter: conntrack: sanitize table size default settingsFlorian Westphal1-5/+8
conntrack has two distinct table size settings: nf_conntrack_max and nf_conntrack_buckets. The former limits how many conntrack objects are allowed to exist in each namespace. The second sets the size of the hashtable. As all entries are inserted twice (once for original direction, once for reply), there should be at least twice as many buckets in the table than the maximum number of conntrack objects that can exist at the same time. Change the default multiplier to 1 and increase the chosen bucket sizes. This results in the same nf_conntrack_max settings as before but reduces the average bucket list length. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-30netfilter: add netfilter hooks to SRv6 data planeRyoga Saito1-0/+7
This patch introduces netfilter hooks for solving the problem that conntrack couldn't record both inner flows and outer flows. This patch also introduces a new sysctl toggle for enabling lightweight tunnel netfilter hooks. Signed-off-by: Ryoga Saito <contact@proelbtn.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-06netfilter: conntrack: remove offload_pickup sysctl againFlorian Westphal1-10/+0
These two sysctls were added because the hardcoded defaults (2 minutes, tcp, 30 seconds, udp) turned out to be too low for some setups. They appeared in 5.14-rc1 so it should be fine to remove it again. Marcelo convinced me that there should be no difference between a flow that was offloaded vs. a flow that was not wrt. timeout handling. Thus the default is changed to those for TCP established and UDP stream, 5 days and 120 seconds, respectively. Marcelo also suggested to account for the timeout value used for the offloading, this avoids increase beyond the value in the conntrack-sysctl and will also instantly expire the conntrack entry with altered sysctls. Example: nf_conntrack_udp_timeout_stream=60 nf_flowtable_udp_timeout=60 This will remove offloaded udp flows after one minute, rather than two. An earlier version of this patch also cleared the ASSURED bit to allow nf_conntrack to evict the entry via early_drop (i.e., table full). However, it looks like we can safely assume that connection timed out via HW is still in established state, so this isn't needed. Quoting Oz: [..] the hardware sends all packets with a set FIN flags to sw. [..] Connections that are aged in hardware are expected to be in the established state. In case it turns out that back-to-sw-path transition can occur for 'dodgy' connections too (e.g., one side disappeared while software-path would have been in RETRANS timeout), we can adjust this later. Cc: Oz Shlomo <ozsh@nvidia.com> Cc: Paul Blakey <paulb@nvidia.com> Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Oz Shlomo <ozsh@nvidia.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-07-06netfilter: conntrack: add new sysctl to disable RST checkAli Abdallah1-0/+6
This patch adds a new sysctl tcp_ignore_invalid_rst to disable marking out of segments RSTs as INVALID. Signed-off-by: Ali Abdallah <aabdallah@suse.de> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-19docs: networking: Update connection tracking offload sysctl parametersOz Shlomo1-0/+24
Document the following connection offload configuration parameters: - nf_flowtable_tcp_timeout - nf_flowtable_tcp_pickup - nf_flowtable_udp_timeout - nf_flowtable_udp_pickup Signed-off-by: Oz Shlomo <ozsh@nvidia.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-04-30docs: networking: convert nf_conntrack-sysctl.txt to ReSTMauro Carvalho Chehab1-0/+179
- add SPDX header; - add a document title; - mark lists as such; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>