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2019-11-12netfilter: nf_tables: Align nft_expr private data to 64-bitLukas Wunner
commit 250367c59e6ba0d79d702a059712d66edacd4a1a upstream. Invoking the following commands on a 32-bit architecture with strict alignment requirements (such as an ARMv7-based Raspberry Pi) results in an alignment exception: # nft add table ip test-ip4 # nft add chain ip test-ip4 output { type filter hook output priority 0; } # nft add rule ip test-ip4 output quota 1025 bytes Alignment trap: not handling instruction e1b26f9f at [<7f4473f8>] Unhandled fault: alignment exception (0x001) at 0xb832e824 Internal error: : 1 [#1] PREEMPT SMP ARM Hardware name: BCM2835 [<7f4473fc>] (nft_quota_do_init [nft_quota]) [<7f447448>] (nft_quota_init [nft_quota]) [<7f4260d0>] (nf_tables_newrule [nf_tables]) [<7f4168dc>] (nfnetlink_rcv_batch [nfnetlink]) [<7f416bd0>] (nfnetlink_rcv [nfnetlink]) [<8078b334>] (netlink_unicast) [<8078b664>] (netlink_sendmsg) [<8071b47c>] (sock_sendmsg) [<8071bd18>] (___sys_sendmsg) [<8071ce3c>] (__sys_sendmsg) [<8071ce94>] (sys_sendmsg) The reason is that nft_quota_do_init() calls atomic64_set() on an atomic64_t which is only aligned to 32-bit, not 64-bit, because it succeeds struct nft_expr in memory which only contains a 32-bit pointer. Fix by aligning the nft_expr private data to 64-bit. Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16netfilter: ctnetlink: don't use conntrack/expect object addresses as idFlorian Westphal
[ Upstream commit 3c79107631db1f7fd32cf3f7368e4672004a3010 ] else, we leak the addresses to userspace via ctnetlink events and dumps. Compute an ID on demand based on the immutable parts of nf_conn struct. Another advantage compared to using an address is that there is no immediate re-use of the same ID in case the conntrack entry is freed and reallocated again immediately. Fixes: 3583240249ef ("[NETFILTER]: nf_conntrack_expect: kill unique ID") Fixes: 7f85f914721f ("[NETFILTER]: nf_conntrack: kill unique ID") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05netfilter: physdev: relax br_netfilter dependencyFlorian Westphal
[ Upstream commit 8e2f311a68494a6677c1724bdcb10bada21af37c ] Following command: iptables -D FORWARD -m physdev ... causes connectivity loss in some setups. Reason is that iptables userspace will probe kernel for the module revision of the physdev patch, and physdev has an artificial dependency on br_netfilter (xt_physdev use makes no sense unless a br_netfilter module is loaded). This causes the "phydev" module to be loaded, which in turn enables the "call-iptables" infrastructure. bridged packets might then get dropped by the iptables ruleset. The better fix would be to change the "call-iptables" defaults to 0 and enforce explicit setting to 1, but that breaks backwards compatibility. This does the next best thing: add a request_module call to checkentry. This was a stray '-D ... -m physdev' won't activate br_netfilter anymore. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-09netfilter: nf_conncount: Fix garbage collection with zonesYi-Hung Wei
commit 21ba8847f857028dc83a0f341e16ecc616e34740 upstream. Currently, we use check_hlist() for garbage colleciton. However, we use the ‘zone’ from the counted entry to query the existence of existing entries in the hlist. This could be wrong when they are in different zones, and this patch fixes this issue. Fixes: e59ea3df3fc2 ("netfilter: xt_connlimit: honor conntrack zone if available") Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names, note hunk 5: - nf_conncount.c -> xt_connlimit.c - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - hunk 5: remove check for non-NULL 'tuple', that isn't required as it's introduced by upstream commit 35d8deb80 ("netfilter: conncount: Support count only use case") which addresses nf_conncount_count() that does not exist yet -- it's introduced by upstream commit 625c556118f3 ("netfilter: connlimit: split xt_connlimit into front and backend"), a refactor change. - nft_connlimit.c -> removed, not used/doesn't exist yet.] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-09netfilter: nf_conncount: expose connection list interfacePablo Neira Ayuso
commit 5e5cbc7b23eaf13e18652c03efbad5be6995de6a upstream. This patch provides an interface to maintain the list of connections and the lookup function to obtain the number of connections in the list. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [mfo: backport: refresh context lines and use older symbol/file names: - nf_conntrack_count.h: new file, add include guards. - nf_conncount.c -> xt_connlimit.c. - nf_conncount_rb -> xt_connlimit_rb - nf_conncount_tuple -> xt_connlimit_conn - conncount_rb_cachep -> connlimit_rb_cachep - conncount_conn_cachep -> connlimit_conn_cachep] Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-07-08netfilter: nf_tables: bogus EBUSY in chain deletionsPablo Neira Ayuso
commit bb7b40aecbf778c0c83a5bd62b0f03ca9f49a618 upstream. When removing a rule that jumps to chain and such chain in the same batch, this bogusly hits EBUSY. Add activate and deactivate operations to expression that can be called from the preparation and the commit/abort phases. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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>
2017-09-08netfilter: nat: Revert "netfilter: nat: convert nat bysrc hash to rhashtable"Florian Westphal
This reverts commit 870190a9ec9075205c0fa795a09fa931694a3ff1. It was not a good idea. The custom hash table was a much better fit for this purpose. A fast lookup is not essential, in fact for most cases there is no lookup at all because original tuple is not taken and can be used as-is. What needs to be fast is insertion and deletion. rhlist removal however requires a rhlist walk. We can have thousands of entries in such a list if source port/addresses are reused for multiple flows, if this happens removal requests are so expensive that deletions of a few thousand flows can take several seconds(!). The advantages that we got from rhashtable are: 1) table auto-sizing 2) multiple locks 1) would be nice to have, but it is not essential as we have at most one lookup per new flow, so even a million flows in the bysource table are not a problem compared to current deletion cost. 2) is easy to add to custom hash table. I tried to add hlist_node to rhlist to speed up rhltable_remove but this isn't doable without changing semantics. rhltable_remove_fast will check that the to-be-deleted object is part of the table and that requires a list walk that we want to avoid. Furthermore, using hlist_node increases size of struct rhlist_head, which in turn increases nf_conn size. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821 Reported-by: Ivan Babrou <ibobrik@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-04net: Remove CONFIG_NETFILTER_DEBUG and _ASSERT() macros.Varsha Rao
This patch removes CONFIG_NETFILTER_DEBUG and _ASSERT() macros as they are no longer required. Replace _ASSERT() macros with WARN_ON(). Signed-off-by: Varsha Rao <rvarsha016@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-04net: Replace NF_CT_ASSERT() with WARN_ON().Varsha Rao
This patch removes NF_CT_ASSERT() and instead uses WARN_ON(). Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
2017-09-04netfilter: remove unused hooknum arg from packet functionsFlorian Westphal
tested with allmodconfig build. Signed-off-by: Florian Westphal <fw@strlen.de>
2017-09-04netfilter: nf_tables: add select_ops for stateful objectsPablo M. Bermudo Garay
This patch adds support for overloading stateful objects operations through the select_ops() callback, just as it is implemented for expressions. This change is needed for upcoming additions to the stateful objects infrastructure. Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28netfilter: convert hook list to an arrayAaron Conole
This converts the storage and layout of netfilter hook entries from a linked list to an array. After this commit, hook entries will be stored adjacent in memory. The next pointer is no longer required. The ops pointers are stored at the end of the array as they are only used in the register/unregister path and in the legacy br_netfilter code. nf_unregister_net_hooks() is slower than needed as it just calls nf_unregister_net_hook in a loop (i.e. at least n synchronize_net() calls), this will be addressed in followup patch. Test setup: - ixgbe 10gbit - netperf UDP_STREAM, 64 byte packets - 5 hooks: (raw + mangle prerouting, mangle+filter input, inet filter): empty mangle and raw prerouting, mangle and filter input hooks: 353.9 this patch: 364.2 Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: make protocol tracker pointers constFlorian Westphal
Doesn't change generated code, but will make it easier to eventually make the actual trackers themselvers const. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: print_conntrack only needed if CONFIG_NF_CONNTRACK_PROCFSFlorian Westphal
Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: place print_tuple in procfs partFlorian Westphal
CONFIG_NF_CONNTRACK_PROCFS is deprecated, no need to use a function pointer in the trackers for this. Place the printf formatting in the one place that uses it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: reduce size of l4protocol trackersFlorian Westphal
can use u16 for both, shrinks size by another 8 bytes. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: remove protocol name from l4proto structFlorian Westphal
no need to waste storage for something that is only needed in one place and can be deduced from protocol number. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: remove protocol name from l3proto structFlorian Westphal
no need to waste storage for something that is only needed in one place and can be deduced from protocol number. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-24netfilter: conntrack: compute l3proto nla size at compile timeFlorian Westphal
avoids a pointer and allows struct to be const later on. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-02netfilter: constify nf_conntrack_l3/4proto parametersJulia Lawall
When a nf_conntrack_l3/4proto parameter is not on the left hand side of an assignment, its address is not taken, and it is not passed to a function that may modify its fields, then it can be declared as const. This change is useful from a documentation point of view, and can possibly facilitate making some nf_conntrack_l3/4proto structures const subsequently. Done with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: conntrack: do not enable connection tracking unless neededFlorian Westphal
Discussion during NFWS 2017 in Faro has shown that the current conntrack behaviour is unreasonable. Even if conntrack module is loaded on behalf of a single net namespace, its turned on for all namespaces, which is expensive. Commit 481fa373476 ("netfilter: conntrack: add nf_conntrack_default_on sysctl") attempted to provide an alternative to the 'default on' behaviour by adding a sysctl to change it. However, as Eric points out, the sysctl only becomes available once the module is loaded, and then its too late. So we either have to move the sysctl to the core, or, alternatively, change conntrack to become active only once the rule set requires this. This does the latter, conntrack is only enabled when a rule needs it. Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: nf_tables: Allow object names of up to 255 charsPhil Sutter
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: nf_tables: Allow set names of up to 255 charsPhil Sutter
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: nf_tables: Allow chain name of up to 255 charsPhil Sutter
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: nf_tables: Allow table names of up to 255 charsPhil Sutter
Allocate all table names dynamically to allow for arbitrary lengths but introduce NFT_NAME_MAXLEN as an upper sanity boundary. It's value was chosen to allow using a domain name as per RFC 1035. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: add and use nf_ct_unconfirmed_destroyFlorian Westphal
This also removes __nf_ct_unconfirmed_destroy() call from nf_ct_iterate_cleanup_net, so that function can be used only when missing conntracks from unconfirmed list isn't a problem. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-31netfilter: expect: add and use nf_ct_expect_iterate helpersFlorian Westphal
We have several spots that open-code a expect walk, add a helper that is similar to nf_ct_iterate_destroy/nf_ct_iterate_cleanup. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-24netfilter: nf_tables: keep chain counters away from hot pathPablo Neira Ayuso
These chain counters are only used by the iptables-compat tool, that allow users to use the x_tables extensions from the existing nf_tables framework. This patch makes nf_tables by ~5% for the general usecase, ie. native nft users, where no chain counters are used at all. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-01net: convert nf_bridge_info.use from atomic_t to refcount_tReshetova, Elena
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-19netfilter: conntrack: use NFPROTO_MAX to size arrayFlorian Westphal
We don't support anything larger than NFPROTO_MAX, so we can shrink this a bit: text data dec hex filename old: 8259 1096 9355 248b net/netfilter/nf_conntrack_proto.o new: 8259 624 8883 22b3 net/netfilter/nf_conntrack_proto.o Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-29netfilter: nf_tables: pass set description to ->privsizePablo Neira Ayuso
The new non-resizable hashtable variant needs this to calculate the size of the bucket array. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-29netfilter: nf_tables: select set backend flavour depending on descriptionPablo Neira Ayuso
This patch adds the infrastructure to support several implementations of the same set type. This selection will be based on the set description and the features available for this set. This allow us to select set backend implementation that will result in better performance numbers. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-29netfilter: conntrack: add nf_ct_iterate_destroyFlorian Westphal
sledgehammer to be used on module unload (to remove affected conntracks from all namespaces). It will also flag all unconfirmed conntracks as dying, i.e. they will not be committed to main table. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-29netfilter: conntrack: rename nf_ct_iterate_cleanupFlorian Westphal
There are several places where we needlesly call nf_ct_iterate_cleanup, we should instead iterate the full table at module unload time. This is a leftover from back when the conntrack table got duplicated per net namespace. So rename nf_ct_iterate_cleanup to nf_ct_iterate_cleanup_net. A later patch will then add a non-net variant. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15netfilter: nf_tables: revisit chain/object refcounting from elementsPablo Neira Ayuso
Andreas reports that the following incremental update using our commit protocol doesn't work. # nft -f incremental-update.nft delete element ip filter client_to_any { 10.180.86.22 : goto CIn_1 } delete chain ip filter CIn_1 ... Error: Could not process rule: Device or resource busy The existing code is not well-integrated into the commit phase protocol, since element deletions do not result in refcount decrement from the preparation phase. This results in bogus EBUSY errors like the one above. Two new functions come with this patch: * nft_set_elem_activate() function is used from the abort path, to restore the set element refcounting on objects that occurred from the preparation phase. * nft_set_elem_deactivate() that is called from nft_del_setelem() to decrement set element refcounting on objects from the preparation phase in the commit protocol. The nft_data_uninit() has been renamed to nft_data_release() since this function does not uninitialize any data store in the data register, instead just releases the references to objects. Moreover, a new function nft_data_hold() has been introduced to be used from nft_set_elem_activate(). Reported-by: Andreas Schultz <aschultz@tpip.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15netfilter: nfnl_cthelper: reject del request if helper obj is in useLiping Zhang
We can still delete the ct helper even if it is in use, this will cause a use-after-free error. In more detail, I mean: # nfct helper add ssdp inet udp # iptables -t raw -A OUTPUT -p udp -j CT --helper ssdp # nfct helper delete ssdp //--> oops, succeed! BUG: unable to handle kernel paging request at 000026ca IP: 0x26ca [...] Call Trace: ? ipv4_helper+0x62/0x80 [nf_conntrack_ipv4] nf_hook_slow+0x21/0xb0 ip_output+0xe9/0x100 ? ip_fragment.constprop.54+0xc0/0xc0 ip_local_out+0x33/0x40 ip_send_skb+0x16/0x80 udp_send_skb+0x84/0x240 udp_sendmsg+0x35d/0xa50 So add reference count to fix this issue, if ct helper is used by others, reject the delete request. Apply this patch: # nfct helper delete ssdp nfct v1.4.3: netlink error: Device or resource busy Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15netfilter: introduce nf_conntrack_helper_put helper functionLiping Zhang
And convert module_put invocation to nf_conntrack_helper_put, this is prepared for the followup patch, which will add a refcnt for cthelper, so we can reject the deleting request when cthelper is in use. Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01netfilter: nf_ct_ext: invoke destroy even when ext is not attachedLiping Zhang
For NF_NAT_MANIP_SRC, we will insert the ct to the nat_bysource_table, then remove it from the nat_bysource_table via nat_extend->destroy. But now, the nat extension is attached on demand, so if the nat extension is not attached, we will not be notified when the ct is destroyed, i.e. we may fail to remove ct from the nat_bysource_table. So just keep it simple, even if the extension is not attached, we will still invoke the related ext->destroy. And this will also preserve the flexibility for the future extension. Fixes: 9a08ecfe74d7 ("netfilter: don't attach a nat extension by default") Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01netfilter: nf_queue: only call synchronize_net twice if nf_queue is activeFlorian Westphal
nf_unregister_net_hook(s) can avoid a second call to synchronize_net, provided there is no nfqueue active in that net namespace (which is the common case). This also gets rid of the extra arg to nf_queue_nf_hook_drop(), normally this gets called during netns cleanup so no packets should be queued. For the rare case of base chain being unregistered or module removal while nfqueue is in use the extra hiccup due to the packet drops isn't a big deal. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-26netfilter: don't attach a nat extension by defaultFlorian Westphal
nowadays the NAT extension only stores the interface index (used to purge connections that got masqueraded when interface goes down) and pptp nat information. Previous patches moved nf_ct_nat_ext_add to those places that need it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-26netfilter: conntrack: mark extension structs as constFlorian Westphal
Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-26netfilter: conntrack: remove prealloc supportFlorian Westphal
It was used by the nat extension, but since commit 7c9664351980 ("netfilter: move nat hlist_head to nf_conn") its only needed for connections that use MASQUERADE target or a nat helper. Also it seems a lot easier to preallocate a fixed size instead. With default settings, conntrack first adds ecache extension (sysctl defaults to 1), so we get 40(ct extension header) + 24 (ecache) == 64 byte on x86_64 for initial allocation. Followup patches can constify the extension structs and avoid the initial zeroing of the entire extension area. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-26netfilter: synproxy: only register hooks when neededFlorian Westphal
Defer registration of the synproxy hooks until the first SYNPROXY rule is added. Also means we only register hooks in namespaces that need it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19nefilter: eache: reduce struct size from 32 to 24 byteFlorian Westphal
Only "cache" needs to use ulong (its used with set_bit()), missed can use u16. Also add build-time assertion to ensure event bits fit. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19netfilter: allow early drop of assured conntracksFlorian Westphal
If insertion of a new conntrack fails because the table is full, the kernel searches the next buckets of the hash slot where the new connection was supposed to be inserted at for an entry that hasn't seen traffic in reply direction (non-assured), if it finds one, that entry is is dropped and the new connection entry is allocated. Allow the conntrack gc worker to also remove *assured* conntracks if resources are low. Do this by querying the l4 tracker, e.g. tcp connections are now dropped if they are no longer established (e.g. in finwait). This could be refined further, e.g. by adding 'soft' established timeout (i.e., a timeout that is only used once we get close to resource exhaustion). Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19netfilter: conntrack: use u8 for extension sizes againFlorian Westphal
commit 223b02d923ecd7c84cf9780bb3686f455d279279 ("netfilter: nf_conntrack: reserve two bytes for nf_ct_ext->len") had to increase size of the extension offsets because total size of the extensions had increased to a point where u8 did overflow. 3 years later we've managed to diet extensions a bit and we no longer need u16. Furthermore we can now add a compile-time assertion for this problem. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19netfilter: remove last traces of variable-sized extensionsFlorian Westphal
get rid of the (now unused) nf_ct_ext_add_length define and also rename the function to plain nf_ct_ext_add(). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19netfilter: helpers: remove data_len usage for inkernel helpersFlorian Westphal
No need to track this for inkernel helpers anymore as NF_CT_HELPER_BUILD_BUG_ON checks do this now. All inkernel helpers know what kind of structure they stored in helper->data. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-19netfilter: helper: add build-time asserts for helper data sizeFlorian Westphal
add a 32 byte scratch area in the helper struct instead of relying on variable sized helpers plus compile-time asserts to let us know if 32 bytes aren't enough anymore. Not having variable sized helpers will later allow to add BUILD_BUG_ON for the total size of conntrack extensions -- the helper extension is the only one that doesn't have a fixed size. The (useless!) NF_CT_HELPER_BUILD_BUG_ON(0); are added so that in case someone adds a new helper and copy-pastes from one that doesn't store private data at least some indication that this macro should be used somehow is there... Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>