linux/include/net/ip_vs.h

1882 lines
54 KiB

License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 15:07:57 +01:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
IPVS: Allow boot time change of hash size I was very frustrated about the fact that I have to recompile the kernel to change the hash size. So, I created this patch. If IPVS is built-in you can append ip_vs.conn_tab_bits=?? to kernel command line, or, if you built IPVS as modules, you can add options ip_vs conn_tab_bits=??. To keep everything backward compatible, you still can select the size at compile time, and that will be used as default. It has been about a year since this patch was originally posted and subsequently dropped on the basis of insufficient test data. Mark Bergsma has provided the following test results which seem to strongly support the need for larger hash table sizes: We do however run into the same problem with the default setting (212 = 4096 entries), as most of our LVS balancers handle around a million connections/SLAB entries at any point in time (around 100-150 kpps load). With only 4096 hash table entries this implies that each entry consists of a linked list of 256 connections *on average*. To provide some statistics, I did an oprofile run on an 2.6.31 kernel, with both the default 4096 table size, and the same kernel recompiled with IP_VS_CONN_TAB_BITS set to 18 (218 = 262144 entries). I built a quick test setup with a part of Wikimedia/Wikipedia's live traffic mirrored by the switch to the test host. With the default setting, at ~ 120 kpps packet load we saw a typical %si CPU usage of around 30-35%, and oprofile reported a hot spot in ip_vs_conn_in_get: samples % image name app name symbol name 1719761 42.3741 ip_vs.ko ip_vs.ko ip_vs_conn_in_get 302577 7.4554 bnx2 bnx2 /bnx2 181984 4.4840 vmlinux vmlinux __ticket_spin_lock 128636 3.1695 vmlinux vmlinux ip_route_input 74345 1.8318 ip_vs.ko ip_vs.ko ip_vs_conn_out_get 68482 1.6874 vmlinux vmlinux mwait_idle After loading the recompiled kernel with 218 entries, %si CPU usage dropped in half to around 12-18%, and oprofile looks much healthier, with only 7% spent in ip_vs_conn_in_get: samples % image name app name symbol name 265641 14.4616 bnx2 bnx2 /bnx2 143251 7.7986 vmlinux vmlinux __ticket_spin_lock 140661 7.6576 ip_vs.ko ip_vs.ko ip_vs_conn_in_get 94364 5.1372 vmlinux vmlinux mwait_idle 86267 4.6964 vmlinux vmlinux ip_route_input [ horms@verge.net.au: trivial up-port and minor style fixes ] Signed-off-by: Catalin(ux) M. BOIE <catab@embedromix.ro> Cc: Mark Bergsma <mark@wikimedia.org> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-01-05 05:50:24 +01:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: Update width of source for ip_vs_sync_conn_options In ip_vs_sync_conn_v0() copy is made to struct ip_vs_sync_conn_options. That structure looks like this: struct ip_vs_sync_conn_options { struct ip_vs_seq in_seq; struct ip_vs_seq out_seq; }; The source of the copy is the in_seq field of struct ip_vs_conn. Whose type is struct ip_vs_seq. Thus we can see that the source - is not as wide as the amount of data copied, which is the width of struct ip_vs_sync_conn_option. The copy is safe because the next field in is another struct ip_vs_seq. Make use of struct_group() to annotate this. Flagged by gcc-13 as: In file included from ./include/linux/string.h:254, from ./include/linux/bitmap.h:11, from ./include/linux/cpumask.h:12, from ./arch/x86/include/asm/paravirt.h:17, from ./arch/x86/include/asm/cpuid.h:62, from ./arch/x86/include/asm/processor.h:19, from ./arch/x86/include/asm/timex.h:5, from ./include/linux/timex.h:67, from ./include/linux/time32.h:13, from ./include/linux/time.h:60, from ./include/linux/stat.h:19, from ./include/linux/module.h:13, from net/netfilter/ipvs/ip_vs_sync.c:38: In function 'fortify_memcpy_chk', inlined from 'ip_vs_sync_conn_v0' at net/netfilter/ipvs/ip_vs_sync.c:606:3: ./include/linux/fortify-string.h:529:25: error: call to '__read_overflow2_field' declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning] 529 | __read_overflow2_field(q_size_field, size); | Compile tested only. Signed-off-by: Simon Horman <horms@kernel.org> Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-17 17:10:45 +02:00
ipvs: make the service replacement more robust commit 578bc3ef1e473a ("ipvs: reorganize dest trash") added IP_VS_DEST_STATE_REMOVING flag and RCU callback named ip_vs_dest_wait_readers() to keep dests and services after removal for at least a RCU grace period. But we have the following corner cases: - we can not reuse the same dest if its service is removed while IP_VS_DEST_STATE_REMOVING is still set because another dest removal in the first grace period can not extend this period. It can happen when ipvsadm -C && ipvsadm -R is used. - dest->svc can be replaced but ip_vs_in_stats() and ip_vs_out_stats() have no explicit read memory barriers when accessing dest->svc. It can happen that dest->svc was just freed (replaced) while we use it to update the stats. We solve the problems as follows: - IP_VS_DEST_STATE_REMOVING is removed and we ensure a fixed idle period for the dest (IP_VS_DEST_TRASH_PERIOD). idle_start will remember when for first time after deletion we noticed dest->refcnt=0. Later, the connections can grab a reference while in RCU grace period but if refcnt becomes 0 we can safely free the dest and its svc. - dest->svc becomes RCU pointer. As result, we add explicit RCU locking in ip_vs_in_stats() and ip_vs_out_stats(). - __ip_vs_unbind_svc is renamed to __ip_vs_svc_put(), it now can free the service immediately or after a RCU grace period. dest->svc is not set to NULL anymore. As result, unlinked dests and their services are freed always after IP_VS_DEST_TRASH_PERIOD period, unused services are freed after a RCU grace period. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2013-09-12 11:21:07 +03:00
ipvs: make the service replacement more robust commit 578bc3ef1e473a ("ipvs: reorganize dest trash") added IP_VS_DEST_STATE_REMOVING flag and RCU callback named ip_vs_dest_wait_readers() to keep dests and services after removal for at least a RCU grace period. But we have the following corner cases: - we can not reuse the same dest if its service is removed while IP_VS_DEST_STATE_REMOVING is still set because another dest removal in the first grace period can not extend this period. It can happen when ipvsadm -C && ipvsadm -R is used. - dest->svc can be replaced but ip_vs_in_stats() and ip_vs_out_stats() have no explicit read memory barriers when accessing dest->svc. It can happen that dest->svc was just freed (replaced) while we use it to update the stats. We solve the problems as follows: - IP_VS_DEST_STATE_REMOVING is removed and we ensure a fixed idle period for the dest (IP_VS_DEST_TRASH_PERIOD). idle_start will remember when for first time after deletion we noticed dest->refcnt=0. Later, the connections can grab a reference while in RCU grace period but if refcnt becomes 0 we can safely free the dest and its svc. - dest->svc becomes RCU pointer. As result, we add explicit RCU locking in ip_vs_in_stats() and ip_vs_out_stats(). - __ip_vs_unbind_svc is renamed to __ip_vs_svc_put(), it now can free the service immediately or after a RCU grace period. dest->svc is not set to NULL anymore. As result, unlinked dests and their services are freed always after IP_VS_DEST_TRASH_PERIOD period, unused services are freed after a RCU grace period. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2013-09-12 11:21:07 +03:00
ipvs: handle connections started by real-servers When using LVS-NAT and SIP persistence-egine over UDP, the following limitations are present with current implementation: 1) To actually have load-balancing based on Call-ID header, you need to use one-packet-scheduling mode. But with one-packet-scheduling the connection is deleted just after packet is forwarded, so SIP responses coming from real-servers do not match any connection and SNAT is not applied. 2) If you do not use "-o" option, IPVS behaves as normal UDP load balancer, so different SIP calls (each one identified by a different Call-ID) coming from the same ip-address/port go to the same real-server. So basically you don’t have load-balancing based on Call-ID as intended. 3) Call-ID is not learned when a new SIP call is started by a real-server (inside-to-outside direction), but only in the outside-to-inside direction. This would be a general problem for all SIP servers acting as Back2BackUserAgent. This patch aims to solve problems 1) and 3) while keeping OPS mode mandatory for SIP-UDP, so that 2) is not a problem anymore. The basic mechanism implemented is to make packets, that do not match any existent connection but come from real-servers, create new connections instead of let them pass without any effect. When such packets pass through ip_vs_out(), if their source ip address and source port match a configured real-server, a new connection is automatically created in the same way as it would have happened if the packet had come from outside-to-inside direction. A new connection template is created too if the virtual-service is persistent and there is no matching connection template found. The new connection automatically created, if the service had "-o" option, is an OPS connection that lasts only the time to forward the packet, just like it happens on the ingress side. The main part of this mechanism is implemented inside a persistent-engine specific callback (at the moment only SIP persistent engine exists) and is triggered only for UDP packets, since connection oriented protocols, by using different set of ports (typically ephemeral ports) to open new outgoing connections, should not need this feature. The following requisites are needed for automatic connection creation; if any is missing the packet simply goes the same way as before. a) virtual-service is not fwmark based (this is because fwmark services do not store address and port of the virtual-service, required to build the connection data). b) virtual-service and real-servers must not have been configured with omitted port (this is again to have all data to create the connection). Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-05 18:26:29 +02:00
ipvs: fix tinfo memory leak in start_sync_thread syzkaller reports for memory leak in start_sync_thread [1] As Eric points out, kthread may start and stop before the threadfn function is called, so there is no chance the data (tinfo in our case) to be released in thread. Fix this by releasing tinfo in the controlling code instead. [1] BUG: memory leak unreferenced object 0xffff8881206bf700 (size 32): comm "syz-executor761", pid 7268, jiffies 4294943441 (age 20.470s) hex dump (first 32 bytes): 00 40 7c 09 81 88 ff ff 80 45 b8 21 81 88 ff ff .@|......E.!.... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000057619e23>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<0000000057619e23>] slab_post_alloc_hook mm/slab.h:439 [inline] [<0000000057619e23>] slab_alloc mm/slab.c:3326 [inline] [<0000000057619e23>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<0000000086ce5479>] kmalloc include/linux/slab.h:547 [inline] [<0000000086ce5479>] start_sync_thread+0x5d2/0xe10 net/netfilter/ipvs/ip_vs_sync.c:1862 [<000000001a9229cc>] do_ip_vs_set_ctl+0x4c5/0x780 net/netfilter/ipvs/ip_vs_ctl.c:2402 [<00000000ece457c8>] nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] [<00000000ece457c8>] nf_setsockopt+0x4c/0x80 net/netfilter/nf_sockopt.c:115 [<00000000942f62d4>] ip_setsockopt net/ipv4/ip_sockglue.c:1258 [inline] [<00000000942f62d4>] ip_setsockopt+0x9b/0xb0 net/ipv4/ip_sockglue.c:1238 [<00000000a56a8ffd>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<00000000fa895401>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000095eef4cf>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<000000009747cf88>] __do_sys_setsockopt net/socket.c:2089 [inline] [<000000009747cf88>] __se_sys_setsockopt net/socket.c:2086 [inline] [<000000009747cf88>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<00000000ded8ba80>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000893b4ac8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported-by: syzbot+7e2e50c8adfccd2e5041@syzkaller.appspotmail.com Suggested-by: Eric Biggers <ebiggers@kernel.org> Fixes: 998e7a76804b ("ipvs: Use kthread_run() instead of doing a double-fork via kernel_thread()") Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-18 23:07:36 +03:00
ipvs: handle connections started by real-servers When using LVS-NAT and SIP persistence-egine over UDP, the following limitations are present with current implementation: 1) To actually have load-balancing based on Call-ID header, you need to use one-packet-scheduling mode. But with one-packet-scheduling the connection is deleted just after packet is forwarded, so SIP responses coming from real-servers do not match any connection and SNAT is not applied. 2) If you do not use "-o" option, IPVS behaves as normal UDP load balancer, so different SIP calls (each one identified by a different Call-ID) coming from the same ip-address/port go to the same real-server. So basically you don’t have load-balancing based on Call-ID as intended. 3) Call-ID is not learned when a new SIP call is started by a real-server (inside-to-outside direction), but only in the outside-to-inside direction. This would be a general problem for all SIP servers acting as Back2BackUserAgent. This patch aims to solve problems 1) and 3) while keeping OPS mode mandatory for SIP-UDP, so that 2) is not a problem anymore. The basic mechanism implemented is to make packets, that do not match any existent connection but come from real-servers, create new connections instead of let them pass without any effect. When such packets pass through ip_vs_out(), if their source ip address and source port match a configured real-server, a new connection is automatically created in the same way as it would have happened if the packet had come from outside-to-inside direction. A new connection template is created too if the virtual-service is persistent and there is no matching connection template found. The new connection automatically created, if the service had "-o" option, is an OPS connection that lasts only the time to forward the packet, just like it happens on the ingress side. The main part of this mechanism is implemented inside a persistent-engine specific callback (at the moment only SIP persistent engine exists) and is triggered only for UDP packets, since connection oriented protocols, by using different set of ports (typically ephemeral ports) to open new outgoing connections, should not need this feature. The following requisites are needed for automatic connection creation; if any is missing the packet simply goes the same way as before. a) virtual-service is not fwmark based (this is because fwmark services do not store address and port of the virtual-service, required to build the connection data). b) virtual-service and real-servers must not have been configured with omitted port (this is again to have all data to create the connection). Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-05 18:26:29 +02:00
ipvs: move old_secure_tcp into struct netns_ipvs syzbot reported the following issue : BUG: KCSAN: data-race in update_defense_level / update_defense_level read to 0xffffffff861a6260 of 4 bytes by task 3006 on cpu 1: update_defense_level+0x621/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:177 defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 write to 0xffffffff861a6260 of 4 bytes by task 7333 on cpu 0: update_defense_level+0xa62/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:205 defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269 worker_thread+0xa0/0x800 kernel/workqueue.c:2415 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 7333 Comm: kworker/0:5 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events defense_work_handler Indeed, old_secure_tcp is currently a static variable, while it needs to be a per netns variable. Fixes: a0840e2e165a ("IPVS: netns, ip_vs_ctl local vars moved to ipvs struct.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Simon Horman <horms@verge.net.au>
2019-10-23 09:53:03 -07:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: fix tinfo memory leak in start_sync_thread syzkaller reports for memory leak in start_sync_thread [1] As Eric points out, kthread may start and stop before the threadfn function is called, so there is no chance the data (tinfo in our case) to be released in thread. Fix this by releasing tinfo in the controlling code instead. [1] BUG: memory leak unreferenced object 0xffff8881206bf700 (size 32): comm "syz-executor761", pid 7268, jiffies 4294943441 (age 20.470s) hex dump (first 32 bytes): 00 40 7c 09 81 88 ff ff 80 45 b8 21 81 88 ff ff .@|......E.!.... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000057619e23>] kmemleak_alloc_recursive include/linux/kmemleak.h:55 [inline] [<0000000057619e23>] slab_post_alloc_hook mm/slab.h:439 [inline] [<0000000057619e23>] slab_alloc mm/slab.c:3326 [inline] [<0000000057619e23>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<0000000086ce5479>] kmalloc include/linux/slab.h:547 [inline] [<0000000086ce5479>] start_sync_thread+0x5d2/0xe10 net/netfilter/ipvs/ip_vs_sync.c:1862 [<000000001a9229cc>] do_ip_vs_set_ctl+0x4c5/0x780 net/netfilter/ipvs/ip_vs_ctl.c:2402 [<00000000ece457c8>] nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] [<00000000ece457c8>] nf_setsockopt+0x4c/0x80 net/netfilter/nf_sockopt.c:115 [<00000000942f62d4>] ip_setsockopt net/ipv4/ip_sockglue.c:1258 [inline] [<00000000942f62d4>] ip_setsockopt+0x9b/0xb0 net/ipv4/ip_sockglue.c:1238 [<00000000a56a8ffd>] udp_setsockopt+0x4e/0x90 net/ipv4/udp.c:2616 [<00000000fa895401>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3130 [<0000000095eef4cf>] __sys_setsockopt+0x98/0x120 net/socket.c:2078 [<000000009747cf88>] __do_sys_setsockopt net/socket.c:2089 [inline] [<000000009747cf88>] __se_sys_setsockopt net/socket.c:2086 [inline] [<000000009747cf88>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2086 [<00000000ded8ba80>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301 [<00000000893b4ac8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported-by: syzbot+7e2e50c8adfccd2e5041@syzkaller.appspotmail.com Suggested-by: Eric Biggers <ebiggers@kernel.org> Fixes: 998e7a76804b ("ipvs: Use kthread_run() instead of doing a double-fork via kernel_thread()") Signed-off-by: Julian Anastasov <ja@ssi.bg> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-18 23:07:36 +03:00
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-23 14:07:29 -07:00
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-23 14:07:29 -07:00
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-23 14:07:29 -07:00
ipvs: handle connections started by real-servers When using LVS-NAT and SIP persistence-egine over UDP, the following limitations are present with current implementation: 1) To actually have load-balancing based on Call-ID header, you need to use one-packet-scheduling mode. But with one-packet-scheduling the connection is deleted just after packet is forwarded, so SIP responses coming from real-servers do not match any connection and SNAT is not applied. 2) If you do not use "-o" option, IPVS behaves as normal UDP load balancer, so different SIP calls (each one identified by a different Call-ID) coming from the same ip-address/port go to the same real-server. So basically you don’t have load-balancing based on Call-ID as intended. 3) Call-ID is not learned when a new SIP call is started by a real-server (inside-to-outside direction), but only in the outside-to-inside direction. This would be a general problem for all SIP servers acting as Back2BackUserAgent. This patch aims to solve problems 1) and 3) while keeping OPS mode mandatory for SIP-UDP, so that 2) is not a problem anymore. The basic mechanism implemented is to make packets, that do not match any existent connection but come from real-servers, create new connections instead of let them pass without any effect. When such packets pass through ip_vs_out(), if their source ip address and source port match a configured real-server, a new connection is automatically created in the same way as it would have happened if the packet had come from outside-to-inside direction. A new connection template is created too if the virtual-service is persistent and there is no matching connection template found. The new connection automatically created, if the service had "-o" option, is an OPS connection that lasts only the time to forward the packet, just like it happens on the ingress side. The main part of this mechanism is implemented inside a persistent-engine specific callback (at the moment only SIP persistent engine exists) and is triggered only for UDP packets, since connection oriented protocols, by using different set of ports (typically ephemeral ports) to open new outgoing connections, should not need this feature. The following requisites are needed for automatic connection creation; if any is missing the packet simply goes the same way as before. a) virtual-service is not fwmark based (this is because fwmark services do not store address and port of the virtual-service, required to build the connection data). b) virtual-service and real-servers must not have been configured with omitted port (this is again to have all data to create the connection). Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-05 18:26:29 +02:00
ipvs: update real-server binding of outgoing connections in SIP-pe Previous patch that introduced handling of outgoing packets in SIP persistent-engine did not call ip_vs_check_template() in case packet was matching a connection template. Assumption was that real-server was healthy, since it was sending a packet just in that moment. There are however real-server fault conditions requiring that association between call-id and real-server (represented by connection template) gets updated. Here is an example of the sequence of events: 1) RS1 is a back2back user agent that handled call-id1 and call-id2 2) RS1 is down and was marked as unavailable 3) new message from outside comes to IPVS with call-id1 4) IPVS reschedules the message to RS2, which becomes new call handler 5) RS2 forwards the message outside, translating call-id1 to call-id2 6) inside pe->conn_out() IPVS matches call-id2 with existing template 7) IPVS does not change association call-id2 <-> RS1 8) new message comes from client with call-id2 9) IPVS reschedules the message to a real-server potentially different from RS2, which is now the correct destination This patch introduces ip_vs_check_template() call in the handling of outgoing packets for SIP-pe. And also introduces a second optional argument for ip_vs_check_template() that allows to check if dest associated to a connection template is the same dest that was identified as the source of the packet. This is to change the real-server bound to a particular call-id independently from its availability status: the idea is that it's more reliable, for in->out direction (where internal network can be considered trusted), to always associate a call-id with the last real-server that used it in one of its messages. Think about above sequence of events where, just after step 5, RS1 returns instead to be available. Comparison of dests is done by simply comparing pointers to struct ip_vs_dest; there should be no cases where struct ip_vs_dest keeps its memory address, but represent a different real-server in terms of ip-address / port. Fixes: 39b972231536 ("ipvs: handle connections started by real-servers") Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-05-16 19:18:09 +02:00
ipvs: handle connections started by real-servers When using LVS-NAT and SIP persistence-egine over UDP, the following limitations are present with current implementation: 1) To actually have load-balancing based on Call-ID header, you need to use one-packet-scheduling mode. But with one-packet-scheduling the connection is deleted just after packet is forwarded, so SIP responses coming from real-servers do not match any connection and SNAT is not applied. 2) If you do not use "-o" option, IPVS behaves as normal UDP load balancer, so different SIP calls (each one identified by a different Call-ID) coming from the same ip-address/port go to the same real-server. So basically you don’t have load-balancing based on Call-ID as intended. 3) Call-ID is not learned when a new SIP call is started by a real-server (inside-to-outside direction), but only in the outside-to-inside direction. This would be a general problem for all SIP servers acting as Back2BackUserAgent. This patch aims to solve problems 1) and 3) while keeping OPS mode mandatory for SIP-UDP, so that 2) is not a problem anymore. The basic mechanism implemented is to make packets, that do not match any existent connection but come from real-servers, create new connections instead of let them pass without any effect. When such packets pass through ip_vs_out(), if their source ip address and source port match a configured real-server, a new connection is automatically created in the same way as it would have happened if the packet had come from outside-to-inside direction. A new connection template is created too if the virtual-service is persistent and there is no matching connection template found. The new connection automatically created, if the service had "-o" option, is an OPS connection that lasts only the time to forward the packet, just like it happens on the ingress side. The main part of this mechanism is implemented inside a persistent-engine specific callback (at the moment only SIP persistent engine exists) and is triggered only for UDP packets, since connection oriented protocols, by using different set of ports (typically ephemeral ports) to open new outgoing connections, should not need this feature. The following requisites are needed for automatic connection creation; if any is missing the packet simply goes the same way as before. a) virtual-service is not fwmark based (this is because fwmark services do not store address and port of the virtual-service, required to build the connection data). b) virtual-service and real-servers must not have been configured with omitted port (this is again to have all data to create the connection). Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-05 18:26:29 +02:00
ipvs: handle connections started by real-servers When using LVS-NAT and SIP persistence-egine over UDP, the following limitations are present with current implementation: 1) To actually have load-balancing based on Call-ID header, you need to use one-packet-scheduling mode. But with one-packet-scheduling the connection is deleted just after packet is forwarded, so SIP responses coming from real-servers do not match any connection and SNAT is not applied. 2) If you do not use "-o" option, IPVS behaves as normal UDP load balancer, so different SIP calls (each one identified by a different Call-ID) coming from the same ip-address/port go to the same real-server. So basically you don’t have load-balancing based on Call-ID as intended. 3) Call-ID is not learned when a new SIP call is started by a real-server (inside-to-outside direction), but only in the outside-to-inside direction. This would be a general problem for all SIP servers acting as Back2BackUserAgent. This patch aims to solve problems 1) and 3) while keeping OPS mode mandatory for SIP-UDP, so that 2) is not a problem anymore. The basic mechanism implemented is to make packets, that do not match any existent connection but come from real-servers, create new connections instead of let them pass without any effect. When such packets pass through ip_vs_out(), if their source ip address and source port match a configured real-server, a new connection is automatically created in the same way as it would have happened if the packet had come from outside-to-inside direction. A new connection template is created too if the virtual-service is persistent and there is no matching connection template found. The new connection automatically created, if the service had "-o" option, is an OPS connection that lasts only the time to forward the packet, just like it happens on the ingress side. The main part of this mechanism is implemented inside a persistent-engine specific callback (at the moment only SIP persistent engine exists) and is triggered only for UDP packets, since connection oriented protocols, by using different set of ports (typically ephemeral ports) to open new outgoing connections, should not need this feature. The following requisites are needed for automatic connection creation; if any is missing the packet simply goes the same way as before. a) virtual-service is not fwmark based (this is because fwmark services do not store address and port of the virtual-service, required to build the connection data). b) virtual-service and real-servers must not have been configured with omitted port (this is again to have all data to create the connection). Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-05 18:26:29 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: use kthreads for stats estimation Estimating all entries in single list in timer context by single CPU causes large latency with multiple IPVS rules as reported in [1], [2], [3]. Spread the estimator structures in multiple chains and use kthread(s) for the estimation. The chains are processed in multiple (50) timer ticks to ensure the 2-second interval between estimations with some accuracy. Every chain is processed under RCU lock. Every kthread works over its own data structure and all such contexts are attached to array. The contexts can be preserved while the kthread tasks are stopped or restarted. When estimators are removed, unused kthread contexts are released and the slots in array are left empty. First kthread determines parameters to use, eg. maximum number of estimators to process per kthread based on chain's length (chain_max), allowing sub-100us cond_resched rate and estimation taking up to 1/8 of the CPU capacity to avoid any problems if chain_max is not correctly calculated. chain_max is calculated taking into account factors such as CPU speed and memory/cache speed where the cache_factor (4) is selected from real tests with current generation of CPU/NUMA configurations to correct the difference in CPU usage between cached (during calc phase) and non-cached (working) state of the estimated per-cpu data. First kthread also plays the role of distributor of added estimators to all kthreads, keeping low the time to add estimators. The optimization is based on the fact that newly added estimator should be estimated after 2 seconds, so we have the time to offload the adding to chain from controlling process to kthread 0. The allocated kthread context may grow from 1 to 50 allocated structures for timer ticks which saves memory for setups with small number of estimators. We also add delayed work est_reload_work that will make sure the kthread tasks are properly started/stopped. ip_vs_start_estimator() is changed to report errors which allows to safely store the estimators in allocated structures. Many thanks to Jiri Wiesner for his valuable comments and for spending a lot of time reviewing and testing the changes on different platforms with 48-256 CPUs and 1-8 NUMA nodes under different cpufreq governors. [1] Report from Yunhong Jiang: https://lore.kernel.org/netdev/D25792C1-1B89-45DE-9F10-EC350DC04ADC@gmail.com/ [2] https://marc.info/?l=linux-virtual-server&m=159679809118027&w=2 [3] Report from Dust: https://archive.linuxvirtualserver.org/html/lvs-devel/2020-12/msg00000.html Signed-off-by: Julian Anastasov <ja@ssi.bg> Cc: yunhong-cgl jiang <xintian1976@gmail.com> Cc: "dust.li" <dust.li@linux.alibaba.com> Reviewed-by: Jiri Wiesner <jwiesner@suse.de> Tested-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-22 18:46:02 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: netfilter connection tracking changes Add more code to IPVS to work with Netfilter connection tracking and fix some problems. - Allow IPVS to be compiled without connection tracking as in 2.6.35 and before. This can avoid keeping conntracks for all IPVS connections because this costs memory. ip_vs_ftp still depends on connection tracking and NAT as implemented for 2.6.36. - Add sysctl var "conntrack" to enable connection tracking for all IPVS connections. For loaded IPVS directors it needs tuning of nf_conntrack_max limit. - Add IP_VS_CONN_F_NFCT connection flag to request the connection to use connection tracking. This allows user space to provide this flag, for example, in dest->conn_flags. This can be useful to request connection tracking per real server instead of forcing it for all connections with the "conntrack" sysctl. This flag is set currently only by ip_vs_ftp and of course by "conntrack" sysctl. - Add ip_vs_nfct.c file to hold all connection tracking code, by this way main code should not depend of netfilter conntrack support. - Return back the ip_vs_post_routing handler as in 2.6.35 and use skb->ipvs_property=1 to allow IPVS to work without connection tracking Connection tracking: - most of the code is already in 2.6.36-rc - alter conntrack reply tuple for LVS-NAT connections when first packet from client is forwarded and conntrack state is NEW or RELATED. Additionally, alter reply for RELATED connections from real server, again for packet in original direction. - add IP_VS_XMIT_TUNNEL to confirm conntrack (without altering reply) for LVS-TUN early because we want to call nf_reset. It is needed because we add IPIP header and the original conntrack should be preserved, not destroyed. The transmitted IPIP packets can reuse same conntrack, so we do not set skb->ipvs_property. - try to destroy conntrack when the IPVS connection is destroyed. It is not fatal if conntrack disappears before that, it depends on the used timers. Fix problems from long time: - add skb->ip_summed = CHECKSUM_NONE for the LVS-TUN transmitters Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Patrick McHardy <kaber@trash.net>
2010-09-21 17:35:41 +02:00
ipvs: allow connection reuse for unconfirmed conntrack YangYuxi is reporting that connection reuse is causing one-second delay when SYN hits existing connection in TIME_WAIT state. Such delay was added to give time to expire both the IPVS connection and the corresponding conntrack. This was considered a rare case at that time but it is causing problem for some environments such as Kubernetes. As nf_conntrack_tcp_packet() can decide to release the conntrack in TIME_WAIT state and to replace it with a fresh NEW conntrack, we can use this to allow rescheduling just by tuning our check: if the conntrack is confirmed we can not schedule it to different real server and the one-second delay still applies but if new conntrack was created, we are free to select new real server without any delays. YangYuxi lists some of the problem reports: - One second connection delay in masquerading mode: https://marc.info/?t=151683118100004&r=1&w=2 - IPVS low throughput #70747 https://github.com/kubernetes/kubernetes/issues/70747 - Apache Bench can fill up ipvs service proxy in seconds #544 https://github.com/cloudnativelabs/kube-router/issues/544 - Additional 1s latency in `host -> service IP -> pod` https://github.com/kubernetes/kubernetes/issues/90854 Fixes: f719e3754ee2 ("ipvs: drop first packet to redirect conntrack") Co-developed-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-07-01 18:17:19 +03:00
ipvs: drop first packet to redirect conntrack Jiri Bohac is reporting for a problem where the attempt to reschedule existing connection to another real server needs proper redirect for the conntrack used by the IPVS connection. For example, when IPVS connection is created to NAT-ed real server we alter the reply direction of conntrack. If we later decide to select different real server we can not alter again the conntrack. And if we expire the old connection, the new connection is left without conntrack. So, the only way to redirect both the IPVS connection and the Netfilter's conntrack is to drop the SYN packet that hits existing connection, to wait for the next jiffie to expire the old connection and its conntrack and to rely on client's retransmission to create new connection as usually. Jiri Bohac provided a fix that drops all SYNs on rescheduling, I extended his patch to do such drops only for connections that use conntrack. Here is the original report from Jiri Bohac: Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead"), new connections to dead servers are redistributed immediately to new servers. The old connection is expired using ip_vs_conn_expire_now() which sets the connection timer to expire immediately. However, before the timer callback, ip_vs_conn_expire(), is run to clean the connection's conntrack entry, the new redistributed connection may already be established and its conntrack removed instead. Fix this by dropping the first packet of the new connection instead, like we do when the destination server is not available. The timer will have deleted the old conntrack entry long before the first packet of the new connection is retransmitted. Fixes: dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead") Signed-off-by: Jiri Bohac <jbohac@suse.cz> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-03-05 15:03:22 +02:00
ipvs: allow connection reuse for unconfirmed conntrack YangYuxi is reporting that connection reuse is causing one-second delay when SYN hits existing connection in TIME_WAIT state. Such delay was added to give time to expire both the IPVS connection and the corresponding conntrack. This was considered a rare case at that time but it is causing problem for some environments such as Kubernetes. As nf_conntrack_tcp_packet() can decide to release the conntrack in TIME_WAIT state and to replace it with a fresh NEW conntrack, we can use this to allow rescheduling just by tuning our check: if the conntrack is confirmed we can not schedule it to different real server and the one-second delay still applies but if new conntrack was created, we are free to select new real server without any delays. YangYuxi lists some of the problem reports: - One second connection delay in masquerading mode: https://marc.info/?t=151683118100004&r=1&w=2 - IPVS low throughput #70747 https://github.com/kubernetes/kubernetes/issues/70747 - Apache Bench can fill up ipvs service proxy in seconds #544 https://github.com/cloudnativelabs/kube-router/issues/544 - Additional 1s latency in `host -> service IP -> pod` https://github.com/kubernetes/kubernetes/issues/90854 Fixes: f719e3754ee2 ("ipvs: drop first packet to redirect conntrack") Co-developed-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-07-01 18:17:19 +03:00
ipvs: drop first packet to redirect conntrack Jiri Bohac is reporting for a problem where the attempt to reschedule existing connection to another real server needs proper redirect for the conntrack used by the IPVS connection. For example, when IPVS connection is created to NAT-ed real server we alter the reply direction of conntrack. If we later decide to select different real server we can not alter again the conntrack. And if we expire the old connection, the new connection is left without conntrack. So, the only way to redirect both the IPVS connection and the Netfilter's conntrack is to drop the SYN packet that hits existing connection, to wait for the next jiffie to expire the old connection and its conntrack and to rely on client's retransmission to create new connection as usually. Jiri Bohac provided a fix that drops all SYNs on rescheduling, I extended his patch to do such drops only for connections that use conntrack. Here is the original report from Jiri Bohac: Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead"), new connections to dead servers are redistributed immediately to new servers. The old connection is expired using ip_vs_conn_expire_now() which sets the connection timer to expire immediately. However, before the timer callback, ip_vs_conn_expire(), is run to clean the connection's conntrack entry, the new redistributed connection may already be established and its conntrack removed instead. Fix this by dropping the first packet of the new connection instead, like we do when the destination server is not available. The timer will have deleted the old conntrack entry long before the first packet of the new connection is retransmitted. Fixes: dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead") Signed-off-by: Jiri Bohac <jbohac@suse.cz> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>
2016-03-05 15:03:22 +02:00