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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>
2021-09-03Merge 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>