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2024-02-28netfilter: nf_tables: allow NFPROTO_INET in nft_(match/target)_validate()Ignat Korchagin1-0/+20
Commit d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family") added some validation of NFPROTO_* families in the nft_compat module, but it broke the ability to use legacy iptables modules in dual-stack nftables. While with legacy iptables one had to independently manage IPv4 and IPv6 tables, with nftables it is possible to have dual-stack tables sharing the rules. Moreover, it was possible to use rules based on legacy iptables match/target modules in dual-stack nftables. As an example, the program from [2] creates an INET dual-stack family table using an xt_bpf based rule, which looks like the following (the actual output was generated with a patched nft tool as the current nft tool does not parse dual stack tables with legacy match rules, so consider it for illustrative purposes only): table inet testfw { chain input { type filter hook prerouting priority filter; policy accept; bytecode counter packets 0 bytes 0 accept } } After d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family") we get EOPNOTSUPP for the above program. Fix this by allowing NFPROTO_INET for nft_(match/target)_validate(), but also restrict the functions to classic iptables hooks. Changes in v3: * clarify that upstream nft will not display such configuration properly and that the output was generated with a patched nft tool * remove example program from commit description and link to it instead * no code changes otherwise Changes in v2: * restrict nft_(match/target)_validate() to classic iptables hooks * rewrite example program to use unmodified libnftnl Fixes: d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family") Link: https://lore.kernel.org/all/Zc1PfoWN38UuFJRI@calendula/T/#mc947262582c90fec044c7a3398cc92fac7afea72 [1] Link: https://lore.kernel.org/all/20240220145509.53357-1-ignat@cloudflare.com/ [2] Reported-by: Jordan Griege <jgriege@cloudflare.com> Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-02-07netfilter: nft_compat: restrict match/target protocol to u16Pablo Neira Ayuso1-1/+7
xt_check_{match,target} expects u16, but NFTA_RULE_COMPAT_PROTO is u32. NLA_POLICY_MAX(NLA_BE32, 65535) cannot be used because .max in nla_policy is s16, see 3e48be05f3c7 ("netlink: add attribute range validation to policy"). Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-02-07netfilter: nft_compat: reject unused compat flagPablo Neira Ayuso1-1/+2
Flag (1 << 0) is ignored is set, never used, reject it it with EINVAL instead. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-02-07netfilter: nft_compat: narrow down revision to unsigned 8-bitsPablo Neira Ayuso1-3/+3
xt_find_revision() expects u8, restrict it to this datatype. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-24netfilter: nf_tables: validate NFPROTO_* familyPablo Neira Ayuso1-0/+12
Several expressions explicitly refer to NF_INET_* hook definitions from expr->ops->validate, however, family is not validated. Bail out with EOPNOTSUPP in case they are used from unsupported families. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Fixes: a3c90f7a2323 ("netfilter: nf_tables: flow offload expression") Fixes: 2fa841938c64 ("netfilter: nf_tables: introduce routing expression") Fixes: 554ced0a6e29 ("netfilter: nf_tables: add support for native socket matching") Fixes: ad49d86e07a4 ("netfilter: nf_tables: Add synproxy support") Fixes: 4ed8eb6570a4 ("netfilter: nf_tables: Add native tproxy support") Fixes: 6c47260250fc ("netfilter: nf_tables: add xfrm expression") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-11-15netfilter: nf_tables: Extend nft_expr_ops::dump callback parametersPhil Sutter1-3/+6
Add a 'reset' flag just like with nft_object_ops::dump. This will be useful to reset "anonymous stateful objects", e.g. simple rule counters. No functional change intended. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-03-20netfilter: nf_tables: do not reduce read-only expressionsPablo Neira Ayuso1-0/+1
Skip register tracking for expressions that perform read-only operations on the registers. Define and use a cookie pointer NFT_REDUCE_READONLY to avoid defining stubs for these expressions. This patch re-enables register tracking which was disabled in ed5f85d42290 ("netfilter: nf_tables: disable register tracking"). Follow up patches add remaining register tracking for existing expressions. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-02-04netfilter: nft_compat: suppress comment matchFlorian Westphal1-0/+9
No need to have the datapath call the always-true comment match stub. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21netfilter: log: work around missing softdep backend moduleFlorian Westphal1-1/+16
iptables/nftables has two types of log modules: 1. backend, e.g. nf_log_syslog, which implement the functionality 2. frontend, e.g. xt_LOG or nft_log, which call the functionality provided by backend based on nf_tables or xtables rule set. Problem is that the request_module() call to load the backed in nf_logger_find_get() might happen with nftables transaction mutex held in case the call path is via nf_tables/nft_compat. This can cause deadlocks (see 'Fixes' tags for details). The chosen solution as to let modprobe deal with this by adding 'pre: ' soft dep tag to xt_LOG (to load the syslog backend) and xt_NFLOG (to load nflog backend). Eric reports that this breaks on systems with older modprobe that doesn't support softdeps. Another, similar issue occurs when someone either insmods xt_(NF)LOG directly or unloads the backend module (possible if no log frontend is in use): because the frontend module is already loaded, modprobe is not invoked again so the softdep isn't evaluated. Add a workaround: If nf_logger_find_get() returns -ENOENT and call is not via nft_compat, load the backend explicitly and try again. Else, let nft_compat ask for deferred request_module via nf_tables infra. Softdeps are kept in-place, so with newer modprobe the dependencies are resolved from userspace. Fixes: cefa31a9d461 ("netfilter: nft_log: perform module load from nf_tables") Fixes: a38b5b56d6f4 ("netfilter: nf_log: add module softdeps") Reported-and-tested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-01netfilter: nft_compat: use nfnetlink_unicast()Pablo Neira Ayuso1-5/+3
Use nfnetlink_unicast() which already translates EAGAIN to ENOBUFS, since EAGAIN is reserved to report missing module dependencies to the nfnetlink core. e0241ae6ac59 ("netfilter: use nfnetlink_unicast() forgot to update this spot. Reported-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07netfilter: nfnetlink: add struct nfgenmsg to struct nfnl_info and use itPablo Neira Ayuso1-11/+6
Update the nfnl_info structure to add a pointer to the nfnetlink header. This simplifies the existing codebase since this header is usually accessed. Update existing clients to use this new field. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-29netfilter: nf_tables: remove xt_action_param from nft_pktinfoFlorian Westphal1-10/+18
Init it on demand in the nft_compat expression. This reduces size of nft_pktinfo from 48 to 24 bytes on x86_64. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-26netfilter: nfnetlink: consolidate callback typesPablo Neira Ayuso1-3/+6
Add enum nfnl_callback_type to identify the callback type to provide one single callback. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-26netfilter: nfnetlink: pass struct nfnl_info to rcu callbacksPablo Neira Ayuso1-13/+11
Update rcu callbacks to use the nfnl_info structure. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31netfilter: add helper function to set up the nfnetlink header and use itPablo Neira Ayuso1-8/+3
This patch adds a helper function to set up the netlink and nfnetlink headers. Update existing codebase to use it. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-08-10netfilter: nft_compat: remove flush counter optimizationFlorian Westphal1-23/+14
WARNING: CPU: 1 PID: 16059 at lib/refcount.c:31 refcount_warn_saturate+0xdf/0xf [..] __nft_mt_tg_destroy+0x42/0x50 [nft_compat] nft_target_destroy+0x63/0x80 [nft_compat] nf_tables_expr_destroy+0x1b/0x30 [nf_tables] nf_tables_rule_destroy+0x3a/0x70 [nf_tables] nf_tables_exit_net+0x186/0x3d0 [nf_tables] Happens when a compat expr is destoyed from abort path. There is no functional impact; after this work queue is flushed unconditionally if its pending. This removes the waitcount optimization. Test of repeated iptables-restore of a ~60k kubernetes ruleset doesn't indicate a slowdown. In case the counter is needed after all for some workloads we can revert this and increment the refcount for the != NFT_PREPARE_TRANS case to avoid the increment/decrement imbalance. While at it, also flush for match case, this was an oversight in the original patch. Fixes: ffe8923f109b7e ("netfilter: nft_compat: make sure xtables destructors have run") Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-07-31netfilter: nft_compat: make sure xtables destructors have runFlorian Westphal1-4/+32
Pablo Neira found that after recent update of xt_IDLETIMER the iptables-nft tests sometimes show an error. He tracked this down to the delayed cleanup used by nf_tables core: del rule (transaction A) add rule (transaction B) Its possible that by time transaction B (both in same netns) runs, the xt target destructor has not been invoked yet. For native nft expressions this is no problem because all expressions that have such side effects make sure these are handled from the commit phase, rather than async cleanup. For nft_compat however this isn't true. Instead of forcing synchronous behaviour for nft_compat, keep track of the number of outstanding destructor calls. When we attempt to create a new expression, flush the cleanup worker to make sure destructors have completed. With lots of help from Pablo Neira. Reported-by: Pablo Neira Ayso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-06-25netfilter: Add MODULE_DESCRIPTION entries to kernel modulesRob Gill1-0/+1
The user tool modinfo is used to get information on kernel modules, including a description where it is available. This patch adds a brief MODULE_DESCRIPTION to netfilter kernel modules (descriptions taken from Kconfig file or code comments) Signed-off-by: Rob Gill <rrobgill@protonmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg1-2/+2
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-27netfilter: nft_compat: use .release_ops and remove list of extensionPablo Neira Ayuso1-226/+55
Add .release_ops, that is called in case of error at a later stage in the expression initialization path, ie. .select_ops() has been already set up operations and that needs to be undone. This allows us to unwind .select_ops from the error path, ie. release the dynamic operations for this extension. Moreover, allocate one single operation instead of recycling them, this comes at the cost of consuming a bit more memory per rule, but it simplifies the infrastructure. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-13netfilter: nft_compat: use-after-free when deleting targetsPablo Neira Ayuso1-1/+2
Fetch pointer to module before target object is released. Fixes: 29e3880109e3 ("netfilter: nf_tables: fix use-after-free when deleting compat expressions") Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-05netfilter: nft_compat: don't use refcount_inc on newly allocated entryFlorian Westphal1-39/+23
When I moved the refcount to refcount_t type I missed the fact that refcount_inc() will result in use-after-free warning with CONFIG_REFCOUNT_FULL=y builds. The correct fix would be to init the reference count to 1 at allocation time, but, unfortunately we cannot do this, as we can't undo that in case something else fails later in the batch. So only solution I see is to special-case the 'new entry' condition and replace refcount_inc() with a "delayed" refcount_set(1) in this case, as done here. The .activate callback can be removed to simplify things, we only need to make sure that deactivate() decrements/unlinks the entry from the list at end of transaction phase (commit or abort). Fixes: 12c44aba6618 ("netfilter: nft_compat: use refcnt_t type for nft_xt reference count") Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-04netfilter: nf_tables: unbind set in rule from commit pathPablo Neira Ayuso1-1/+5
Anonymous sets that are bound to rules from the same transaction trigger a kernel splat from the abort path due to double set list removal and double free. This patch updates the logic to search for the transaction that is responsible for creating the set and disable the set list removal and release, given the rule is now responsible for this. Lookup is reverse since the transaction that adds the set is likely to be at the tail of the list. Moreover, this patch adds the unbind step to deliver the event from the commit path. This should not be done from the worker thread, since we have no guarantees of in-order delivery to the listener. This patch removes the assumption that both activate and deactivate callbacks need to be provided. Fixes: cd5125d8f518 ("netfilter: nf_tables: split set destruction in deactivate and destroy phase") Reported-by: Mikhail Morfikov <mmorfikov@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18netfilter: nft_compat: destroy function must not have side effectsFlorian Westphal1-1/+47
The nft_compat destroy function deletes the nft_xt object from a list. This isn't allowed anymore. Destroy functions are called asynchronously, i.e. next batch can find the object that has a pending ->destroy() invocation: cpu0 cpu1 worker ->destroy for_each_entry() if (x == ... return x->ops; list_del(x) kfree_rcu(x) expr->ops->... // ops was free'd To resolve this, the list_del needs to occur before the transaction mutex gets released. nf_tables has a 'deactivate' hook for this purpose, so use that to unlink the object from the list. Fixes: 0935d5588400 ("netfilter: nf_tables: asynchronous release") Reported-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18netfilter: nft_compat: make lists per netnsFlorian Westphal1-40/+89
There are two problems with nft_compat since the netlink config plane uses a per-netns mutex: 1. Concurrent add/del accesses to the same list 2. accesses to a list element after it has been free'd already. This patch fixes the first problem. Freeing occurs from a work queue, after transaction mutexes have been released, i.e., it still possible for a new transaction (even from same net ns) to find the to-be-deleted expression in the list. The ->destroy functions are not allowed to have any such side effects, i.e. the list_del() in the destroy function is not allowed. This part of the problem is solved in the next patch. I tried to make this work by serializing list access via mutex and by moving list_del() to a deactivate callback, but Taehee spotted following race on this approach: NET #0 NET #1 >select_ops() ->init() ->select_ops() ->deactivate() ->destroy() nft_xt_put() kfree_rcu(xt, rcu_head); ->init() <-- use-after-free occurred. Unfortunately, we can't increment reference count in select_ops(), because we can't undo the refcount increase in case a different expression fails in the same batch. (The destroy hook will only be called in case the expression was initialized successfully). Fixes: f102d66b335a ("netfilter: nf_tables: use dedicated mutex to guard transactions") Reported-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18netfilter: nft_compat: use refcnt_t type for nft_xt reference countFlorian Westphal1-8/+8
Using standard integer type was fine while all operations on it were guarded by the nftnl subsys mutex. This isn't true anymore: 1. transactions are guarded only by a pernet mutex, so concurrent rule manipulation in different netns is racy 2. the ->destroy hook runs from a work queue after the transaction mutex has been released already. cpu0 cpu1 (net 1) cpu2 (net 2) kworker nft_compat->destroy nft_compat->init nft_compat->init if (--nft_xt->ref == 0) nft_xt->ref++ nft_xt->ref++ Switch to refcount_t. Doing this however only fixes a minor aspect, nft_compat also performs linked-list operations in an unsafe way. This is addressed in the next two patches. Fixes: f102d66b335a ("netfilter: nf_tables: use dedicated mutex to guard transactions") Fixes: 0935d5588400 ("netfilter: nf_tables: asynchronous release") Reported-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-13netfilter: nf_tables: fix use-after-free when deleting compat expressionsFlorian Westphal1-1/+2
nft_compat ops do not have static storage duration, unlike all other expressions. When nf_tables_expr_destroy() returns, expr->ops might have been free'd already, so we need to store next address before calling expression destructor. For same reason, we can't deref match pointer after nft_xt_put(). This can be easily reproduced by adding msleep() before nft_match_destroy() returns. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Reported-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-03netfilter: nft_compat: ebtables 'nat' table is normal chain typeFlorian Westphal1-9/+12
Unlike ip(6)tables, the ebtables nat table has no special properties. This bug causes 'ebtables -A' to fail when using a target such as 'snat' (ebt_snat target sets ".table = "nat"'). Targets that have no table restrictions work fine. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-10-11netfilter: nft_compat: do not dump private areaPablo Neira Ayuso1-2/+22
Zero pad private area, otherwise we expose private kernel pointer to userspace. This patch also zeroes the tail area after the ->matchsize and ->targetsize that results from XT_ALIGN(). Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Reported-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-07-09netfilter: nft_compat: explicitly reject ERROR and standard targetFlorian Westphal1-0/+13
iptables-nft never requests these, but make this explicitly illegal. If it were quested, kernel could oops as ->eval is NULL, furthermore, the builtin targets have no owning module so its possible to rmmod eb/ip/ip6_tables module even if they would be loaded. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-29netfilter: nft_compat: use call_rcu for nfnl_compat_getFlorian Westphal1-11/+18
Just use .call_rcu instead. We can drop the rcu read lock after obtaining a reference and re-acquire on return. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-09netfilter: nft_compat: fix handling of large matchinfo sizeFlorian Westphal1-1/+63
currently matchinfo gets stored in the expression, but some xt matches are very large. To handle those we either need to switch nft core to kvmalloc and increase size limit, or allocate the info blob of large matches separately. This does the latter, this limits the scope of the changes to nft_compat. I picked a threshold of 192, this allows most matches to work as before and handle only few ones via separate alloation (cgroup, u32, sctp, rt). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-09netfilter: nft_compat: prepare for indirect info storageFlorian Westphal1-11/+36
Next patch will make it possible for *info to be stored in a separate allocation instead of the expr private area. This removes the 'expr priv area is info blob' assumption from the match init/destroy/eval functions. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-08netfilter: nf_tables: nft_compat: fix refcount leak on xt moduleFlorian Westphal1-34/+58
Taehee Yoo reported following bug: iptables-compat -I OUTPUT -m cpu --cpu 0 iptables-compat -F lsmod |grep xt_cpu xt_cpu 16384 1 Quote: "When above command is given, a netlink message has two expressions that are the cpu compat and the nft_counter. The nft_expr_type_get() in the nf_tables_expr_parse() successes first expression then, calls select_ops callback. (allocates memory and holds module) But, second nft_expr_type_get() in the nf_tables_expr_parse() returns -EAGAIN because of request_module(). In that point, by the 'goto err1', the 'module_put(info[i].ops->type->owner)' is called. There is no release routine." The core problem is that unlike all other expression, nft_compat select_ops has side effects. 1. it allocates dynamic memory which holds an nft ops struct. In all other expressions, ops has static storage duration. 2. It grabs references to the xt module that it is supposed to invoke. Depending on where things go wrong, error unwinding doesn't always do the right thing. In the above scenario, a new nft_compat_expr is created and xt_cpu module gets loaded with a refcount of 1. Due to to -EAGAIN, the netlink messages get re-parsed. When that happens, nft_compat finds that xt_cpu is already present and increments module refcount again. This fixes the problem by making select_ops to have no visible side effects and removes all extra module_get/put. When select_ops creates a new nft_compat expression, the new expression has a refcount of 0, and the xt module gets its refcount incremented. When error happens, the next call finds existing entry, but will no longer increase the reference count -- the presence of existing nft_xt means we already hold a module reference. Because nft_xt_put is only called from nft_compat destroy hook, it will never see the initial zero reference count. ->destroy can only be called after ->init(), and that will increase the refcount. Lastly, we now free nft_xt struct with kfree_rcu. Else, we get use-after free in nf_tables_rule_destroy: while (expr != nft_expr_last(rule) && expr->ops) { nf_tables_expr_destroy(ctx, expr); expr = nft_expr_next(expr); // here nft_expr_next() dereferences expr->ops. This is safe for all users, as ops have static storage duration. In nft_compat case however, its ->destroy callback can free the memory that hold the ops structure. Tested-by: Taehee Yoo <ap420073@gmail.com> Reported-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-19netfilter: remove messages print and boot/module load timePablo Neira Ayuso1-2/+0
Several reasons for this: * Several modules maintain internal version numbers, that they print at boot/module load time, that are not exposed to userspace, as a primitive mechanism to make revision number control from the earlier days of Netfilter. * IPset shows the protocol version at boot/module load time, instead display this via module description, as Jozsef suggested. * Remove copyright notice at boot/module load time in two spots, the Netfilter codebase is a collective development effort, if we would have to display copyrights for each contributor at boot/module load time for each extensions we have, we would probably fill up logs with lots of useless information - from a technical standpoint. So let's be consistent and remove them all. Acked-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-10netfilter: nf_tables: add single table list for all familiesPablo Neira Ayuso1-8/+8
Place all existing user defined tables in struct net *, instead of having one list per family. This saves us from one level of indentation in netlink dump functions. Place pointer to struct nft_af_info in struct nft_table temporarily, as we still need this to put back reference module reference counter on table removal. This patch comes in preparation for the removal of struct nft_af_info. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08netfilter: nf_tables: remove multihook chains and familiesPablo Neira Ayuso1-4/+4
Since NFPROTO_INET is handled from the core, we don't need to maintain extra infrastructure in nf_tables to handle the double hook registration, one for IPv4 and another for IPv6. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-19netfilter: nft_compat: check extension hook mask only if setPablo Neira Ayuso1-2/+2
If the x_tables extension comes with no hook mask, skip this validation. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-06-19netfilter: nfnetlink: extended ACK reportingPablo Neira Ayuso1-1/+2
Pass down struct netlink_ext_ack as parameter to all of our nfnetlink subsystem callbacks, so we can work on follow up patches to provide finer grain error reporting using the new infrastructure that 2d4bc93368f5 ("netlink: extended ACK reporting") provides. No functional change, just pass down this new object to callbacks. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-6/+7
Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter updates for your net-next tree. A large bunch of code cleanups, simplify the conntrack extension codebase, get rid of the fake conntrack object, speed up netns by selective synchronize_net() calls. More specifically, they are: 1) Check for ct->status bit instead of using nfct_nat() from IPVS and Netfilter codebase, patch from Florian Westphal. 2) Use kcalloc() wherever possible in the IPVS code, from Varsha Rao. 3) Simplify FTP IPVS helper module registration path, from Arushi Singhal. 4) Introduce nft_is_base_chain() helper function. 5) Enforce expectation limit from userspace conntrack helper, from Gao Feng. 6) Add nf_ct_remove_expect() helper function, from Gao Feng. 7) NAT mangle helper function return boolean, from Gao Feng. 8) ctnetlink_alloc_expect() should only work for conntrack with helpers, from Gao Feng. 9) Add nfnl_msg_type() helper function to nfnetlink to build the netlink message type. 10) Get rid of unnecessary cast on void, from simran singhal. 11) Use seq_puts()/seq_putc() instead of seq_printf() where possible, also from simran singhal. 12) Use list_prev_entry() from nf_tables, from simran signhal. 13) Remove unnecessary & on pointer function in the Netfilter and IPVS code. 14) Remove obsolete comment on set of rules per CPU in ip6_tables, no longer true. From Arushi Singhal. 15) Remove duplicated nf_conntrack_l4proto_udplite4, from Gao Feng. 16) Remove unnecessary nested rcu_read_lock() in __nf_nat_decode_session(). Code running from hooks are already guaranteed to run under RCU read side. 17) Remove deadcode in nf_tables_getobj(), from Aaron Conole. 18) Remove double assignment in nf_ct_l4proto_pernet_unregister_one(), also from Aaron. 19) Get rid of unsed __ip_set_get_netlink(), from Aaron Conole. 20) Don't propagate NF_DROP error to userspace via ctnetlink in __nf_nat_alloc_null_binding() function, from Gao Feng. 21) Revisit nf_ct_deliver_cached_events() to remove unnecessary checks, from Gao Feng. 22) Kill the fake untracked conntrack objects, use ctinfo instead to annotate a conntrack object is untracked, from Florian Westphal. 23) Remove nf_ct_is_untracked(), now obsolete since we have no conntrack template anymore, from Florian. 24) Add event mask support to nft_ct, also from Florian. 25) Move nf_conn_help structure to include/net/netfilter/nf_conntrack_helper.h. 26) Add a fixed 32 bytes scratchpad area for conntrack helpers. Thus, we don't deal with variable conntrack extensions anymore. Make sure userspace conntrack helper doesn't go over that size. Remove variable size ct extension infrastructure now this code got no more clients. From Florian Westphal. 27) Restore offset and length of nf_ct_ext structure to 8 bytes now that wraparound is not possible any longer, also from Florian. 28) Allow to get rid of unassured flows under stress in conntrack, this applies to DCCP, SCTP and TCP protocols, from Florian. 29) Shrink size of nf_conntrack_ecache structure, from Florian. 30) Use TCP_MAX_WSCALE instead of hardcoded 14 in TCP tracker, from Gao Feng. 31) Register SYNPROXY hooks on demand, from Florian Westphal. 32) Use pernet hook whenever possible, instead of global hook registration, from Florian Westphal. 33) Pass hook structure to ebt_register_table() to consolidate some infrastructure code, from Florian Westphal. 34) Use consume_skb() and return NF_STOLEN, instead of NF_DROP in the SYNPROXY code, to make sure device stats are not fooled, patch from Gao Feng. 35) Remove NF_CT_EXT_F_PREALLOC this kills quite some code that we don't need anymore if we just select a fixed size instead of expensive runtime time calculation of this. From Florian. 36) Constify nf_ct_extend_register() and nf_ct_extend_unregister(), from Florian. 37) Simplify nf_ct_ext_add(), this kills nf_ct_ext_create(), from Florian. 38) Attach NAT extension on-demand from masquerade and pptp helper path, from Florian. 39) Get rid of useless ip_vs_set_state_timeout(), from Aaron Conole. 40) Speed up netns by selective calls of synchronize_net(), from Florian Westphal. 41) Silence stack size warning gcc in 32-bit arch in snmp helper, from Florian. 42) Inconditionally call nf_ct_ext_destroy(), even if we have no extensions, to deal with the NF_NAT_MANIP_SRC case. Patch from Liping Zhang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg1-1/+1
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-07netfilter: Add nfnl_msg_type() helper functionPablo Neira Ayuso1-1/+1
Add and use nfnl_msg_type() function to replace opencoded nfnetlink message type. I suggested this change, Arushi Singhal made an initial patch to address this but was missing several spots. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-06netfilter: nf_tables: add nft_is_base_chain() helperPablo Neira Ayuso1-5/+6
This new helper function allows us to check if this is a basechain. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-06netfilter: nf_tables: validate the expr explicitly after init successfullyLiping Zhang1-8/+0
When we want to validate the expr's dependency or hooks, we must do two things to accomplish it. First, write a X_validate callback function and point ->validate to it. Second, call X_validate in init routine. This is very common, such as fib, nat, reject expr and so on ... It is a little ugly, since we will call X_validate in the expr's init routine, it's better to do it in nf_tables_newexpr. So we can avoid to do this again and again. After doing this, the second step listed above is not useful anymore, remove them now. Patch was tested by nftables/tests/py/nft-test.py and nftables/tests/shell/run-tests.sh. Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-23netfilter: nft_compat: fix crash when related match/target module is removedLiping Zhang1-23/+20
We "cache" the loaded match/target modules and reuse them, but when the modules are removed, we still point to them. Then we may end up with invalid memory references when using iptables-compat to add rules later. Input the following commands will reproduce the kernel crash: # iptables-compat -A INPUT -j LOG # iptables-compat -D INPUT -j LOG # rmmod xt_LOG # iptables-compat -A INPUT -j LOG BUG: unable to handle kernel paging request at ffffffffa05a9010 IP: [<ffffffff813f783e>] strcmp+0xe/0x30 Call Trace: [<ffffffffa05acc43>] nft_target_select_ops+0x83/0x1f0 [nft_compat] [<ffffffffa058a177>] nf_tables_expr_parse+0x147/0x1f0 [nf_tables] [<ffffffffa058e541>] nf_tables_newrule+0x301/0x810 [nf_tables] [<ffffffff8141ca00>] ? nla_parse+0x20/0x100 [<ffffffffa057fa8f>] nfnetlink_rcv+0x33f/0x53d [nfnetlink] [<ffffffffa057f94b>] ? nfnetlink_rcv+0x1fb/0x53d [nfnetlink] [<ffffffff817116b8>] netlink_unicast+0x178/0x220 [<ffffffff81711a5b>] netlink_sendmsg+0x2fb/0x3a0 [<ffffffff816b7fc8>] sock_sendmsg+0x38/0x50 [<ffffffff816b8a7e>] ___sys_sendmsg+0x28e/0x2a0 [<ffffffff816bcb7e>] ? release_sock+0x1e/0xb0 [<ffffffff81804ac5>] ? _raw_spin_unlock_bh+0x35/0x40 [<ffffffff816bcbe2>] ? release_sock+0x82/0xb0 [<ffffffff816b93d4>] __sys_sendmsg+0x54/0x90 [<ffffffff816b9422>] SyS_sendmsg+0x12/0x20 [<ffffffff81805172>] entry_SYSCALL_64_fastpath+0x1a/0xa9 So when nobody use the related match/target module, there's no need to "cache" it. And nft_[match|target]_release are useless anymore, remove them. Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-23netfilter: nft_compat: put back match/target module if init failLiping Zhang1-8/+24
If the user specify the invalid NFTA_MATCH_INFO/NFTA_TARGET_INFO attr or memory alloc fail, we should call module_put to the related match or target. Otherwise, we cannot remove the module even nobody use it. Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-11netfilter: nft_compat: check match/targetinfo attr sizeFlorian Westphal1-0/+6
We copy according to ->target|matchsize, so check that the netlink attribute (which can include padding and might be larger) contains enough data. Reported-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-28netfilter: nfnetlink: pass down netns pointer to call() and call_rcu()Pablo Neira Ayuso1-3/+3
Adapt callsites to avoid recurrent lookup of the netns pointer. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-14netfilter: nft_compat: skip family comparison in case of NFPROTO_UNSPECPablo Neira Ayuso1-6/+18
Fix lookup of existing match/target structures in the corresponding list by skipping the family check if NFPROTO_UNSPEC is used. This is resulting in the allocation and insertion of one match/target structure for each use of them. So this not only bloats memory consumption but also severely affects the time to reload the ruleset from the iptables-compat utility. After this patch, iptables-compat-restore and iptables-compat take almost the same time to reload large rulesets. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-05-15netfilter: x_tables: add context to know if extension runs from nft_compatPablo Neira Ayuso1-0/+2
Currently, we have four xtables extensions that cannot be used from the xt over nft compat layer. The problem is that they need real access to the full blown xt_entry to validate that the rule comes with the right dependencies. This check was introduced to overcome the lack of sufficient userspace dependency validation in iptables. To resolve this problem, this patch introduces a new field to the xt_tgchk_param structure that tell us if the extension is run from nft_compat context. The three affected extensions are: 1) CLUSTERIP, this target has been superseded by xt_cluster. So just bail out by returning -EINVAL. 2) TCPMSS. Relax the checking when used from nft_compat. If used with the wrong configuration, it will corrupt !syn packets by adding TCP MSS option. 3) ebt_stp. Relax the check to make sure it uses the reserved destination MAC address for STP. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Tested-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
2015-04-13netfilter: nf_tables: get rid of NFT_REG_VERDICT usagePatrick McHardy1-13/+13
Replace the array of registers passed to expressions by a struct nft_regs, containing the verdict as a seperate member, which aliases to the NFT_REG_VERDICT register. This is needed to seperate the verdict from the data registers completely, so their size can be changed. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-04-08netfilter: Fix switch statement warnings with recent gcc.David Miller1-3/+3
More recent GCC warns about two kinds of switch statement uses: 1) Switching on an enumeration, but not having an explicit case statement for all members of the enumeration. To show the compiler this is intentional, we simply add a default case with nothing more than a break statement. 2) Switching on a boolean value. I think this warning is dumb but nevertheless you get it wholesale with -Wswitch. This patch cures all such warnings in netfilter. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-03-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+6
Conflicts: net/netfilter/nf_tables_core.c The nf_tables_core.c conflict was resolved using a conflict resolution from Stephen Rothwell as a guide. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-22netfilter: nft_compat: set IP6T_F_PROTO flag if protocol is setPablo Neira Ayuso1-0/+6
ip6tables extensions check for this flag to restrict match/target to a given protocol. Without this flag set, SYNPROXY6 returns an error. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Patrick McHardy <kaber@trash.net>
2015-03-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-7/+7
Conflicts: drivers/net/ethernet/cadence/macb.c Overlapping changes in macb driver, mostly fixes and cleanups in 'net' overlapping with the integration of at91_ether into macb in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+10
Conflicts: drivers/net/ethernet/rocker/rocker.c The rocker commit was two overlapping changes, one to rename the ->vport member to ->pport, and another making the bitmask expression use '1ULL' instead of plain '1'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02netfilter: nft_compat: add support for arptables extensionsArturo Borrero1-0/+9
This patch adds support to arptables extensions from nft_compat. Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-02-22netfilter: nft_compat: don't truncate ethernet protocol type to u8Arturo Borrero1-7/+7
Use u16 for protocol and then cast it to __be16 >> net/netfilter/nft_compat.c:140:37: sparse: incorrect type in assignment (different base types) net/netfilter/nft_compat.c:140:37: expected restricted __be16 [usertype] ethproto net/netfilter/nft_compat.c:140:37: got unsigned char [unsigned] [usertype] proto >> net/netfilter/nft_compat.c:351:37: sparse: incorrect type in assignment (different base types) net/netfilter/nft_compat.c:351:37: expected restricted __be16 [usertype] ethproto net/netfilter/nft_compat.c:351:37: got unsigned char [unsigned] [usertype] proto Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-02-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller1-2/+10
Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following patchset contains updates for your net tree, they are: 1) Fix removal of destination in IPVS when the new mixed family support is used, from Alexey Andriyanov via Simon Horman. 2) Fix module refcount undeflow in nft_compat when reusing a match / target. 3) Fix iptables-restore when the recent match is used with a new hitcount that exceeds threshold, from Florian Westphal. 4) Fix stack corruption in xt_socket due to using stack storage to save the inner IPv6 header, from Eric Dumazet. I'll follow up soon with another batch with more fixes that are still cooking. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-16netfilter: nft_compat: fix module refcount underflowPablo Neira Ayuso1-2/+10
Feb 12 18:20:42 nfdev kernel: ------------[ cut here ]------------ Feb 12 18:20:42 nfdev kernel: WARNING: CPU: 4 PID: 4359 at kernel/module.c:963 module_put+0x9b/0xba() Feb 12 18:20:42 nfdev kernel: CPU: 4 PID: 4359 Comm: ebtables-compat Tainted: G W 3.19.0-rc6+ #43 [...] Feb 12 18:20:42 nfdev kernel: Call Trace: Feb 12 18:20:42 nfdev kernel: [<ffffffff815fd911>] dump_stack+0x4c/0x65 Feb 12 18:20:42 nfdev kernel: [<ffffffff8103e6f7>] warn_slowpath_common+0x9c/0xb6 Feb 12 18:20:42 nfdev kernel: [<ffffffff8109919f>] ? module_put+0x9b/0xba Feb 12 18:20:42 nfdev kernel: [<ffffffff8103e726>] warn_slowpath_null+0x15/0x17 Feb 12 18:20:42 nfdev kernel: [<ffffffff8109919f>] module_put+0x9b/0xba Feb 12 18:20:42 nfdev kernel: [<ffffffff813ecf7c>] nft_match_destroy+0x45/0x4c Feb 12 18:20:42 nfdev kernel: [<ffffffff813e683f>] nf_tables_rule_destroy+0x28/0x70 Reported-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Tested-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
2015-01-30netfilter: nft_compat: add ebtables supportArturo Borrero1-6/+57
This patch extends nft_compat to support ebtables extensions. ebtables verdict codes are translated to the ones used by the nf_tables engine, so we can properly use ebtables target extensions from nft_compat. This patch extends previous work by Giuseppe Longo <giuseppelng@gmail.com>. Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-11-12netfilter: nft_compat: use the match->table to validate dependenciesPablo Neira Ayuso1-2/+2
Instead of the match->name, which is of course not relevant. Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-11-12netfilter: nft_compat: relax chain type validationPablo Neira Ayuso1-30/+2
Check for nat chain dependency only, which is the one that can actually crash the kernel. Don't care if mangle, filter and security specific match and targets are used out of their scope, they are harmless. This restores iptables-compat with mangle specific match/target when used out of the OUTPUT chain, that are actually emulated through filter chains, which broke when performing strict validation. Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-11-12netfilter: nft_compat: use current net namespacePablo Neira Ayuso1-2/+2
Instead of init_net when using xtables over nftables compat. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-27netfilter: nft_compat: fix wrong target lookup in nft_target_select_ops()Arturo Borrero1-1/+1
The code looks for an already loaded target, and the correct list to search is nft_target_list, not nft_match_list. Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-18netfilter: nft_compat: validate chain type in match/targetPablo Neira Ayuso1-9/+66
We have to validate the real chain type to ensure that matches/targets are not used out from their scope (eg. MASQUERADE in nat chain type). The existing validation relies on the table name, but this is not sufficient since userspace can fool us by using the appropriate table name with a different chain type. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-14netfilter: nft_compat: fix hook validation for non-base chainsPablo Neira Ayuso1-0/+4
Set hook_mask to zero for non-base chains, otherwise people may hit bogus errors from the xt_check_target() and xt_check_match() when validating the uninitialized hook_mask. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-10-02netfilter: nft_compat: remove incomplete 32/64 bits arch compat codePablo Neira Ayuso1-101/+15
This code was based on the wrong asumption that you can probe based on the match/target private size that we get from userspace. This doesn't work at all when you have to dump the info back to userspace since you don't know what word size the userspace utility is using. Currently, the extensions that require arch compat are limit match and the ebt_mark match/target. The standard targets are not used by the nft-xt compat layer, so they are not affected. We can work around this limitation with a new revision that uses arch agnostic types. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-06-16netfilter: nft_compat: call {target, match}->destroy() to cleanup entryPablo Neira Ayuso1-0/+18
Otherwise, the reference to external objects (eg. modules) are not released when the rules are removed. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-08netfilter: nf_tables: restore context for expression destructorsPatrick McHardy1-2/+2
In order to fix set destruction notifications and get rid of unnecessary members in private data structures, pass the context to expressions' destructor functions again. In order to do so, replace various members in the nft_rule_trans structure by the full context. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-01-07netfilter: nf_tables: add support for multi family tablesPatrick McHardy1-4/+4
Add support to register chains to multiple hooks for different address families for mixed IPv4/IPv6 tables. Signed-off-by: Patrick McHardy <kaber@trash.net>
2013-11-18netfilter: nft_compat: fix error path in nft_parse_compat()Pablo Neira Ayuso1-6/+13
The patch 0ca743a55991: "netfilter: nf_tables: add compatibility layer for x_tables", leads to the following Smatch warning: "net/netfilter/nft_compat.c:140 nft_parse_compat() warn: signedness bug returning '(-34)'" This nft_parse_compat function returns error codes but the return type is u8 so the error codes are transformed into small positive values. The callers don't check the return. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-11-04netfilter: nft_compat: use _safe version of list_for_eachDan Carpenter1-4/+4
We need to use the _safe version of list_for_each_entry() here otherwise we have a use after free bug. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-10-14netfilter: nf_tables: add compatibility layer for x_tablesPablo Neira Ayuso1-0/+768
This patch adds the x_tables compatibility layer. This allows you to use existing x_tables matches and targets from nf_tables. This compatibility later allows us to use existing matches/targets for features that are still missing in nf_tables. We can progressively replace them with native nf_tables extensions. It also provides the userspace compatibility software that allows you to express the rule-set using the iptables syntax but using the nf_tables kernel components. In order to get this compatibility layer working, I've done the following things: * add NFNL_SUBSYS_NFT_COMPAT: this new nfnetlink subsystem is used to query the x_tables match/target revision, so we don't need to use the native x_table getsockopt interface. * emulate xt structures: this required extending the struct nft_pktinfo to include the fragment offset, which is already obtained from ip[6]_tables and that is used by some matches/targets. * add support for default policy to base chains, required to emulate x_tables. * add NFTA_CHAIN_USE attribute to obtain the number of references to chains, required by x_tables emulation. * add chain packet/byte counters using per-cpu. * support 32-64 bits compat. For historical reasons, this patch includes the following patches that were posted in the netfilter-devel mailing list. From Pablo Neira Ayuso: * nf_tables: add default policy to base chains * netfilter: nf_tables: add NFTA_CHAIN_USE attribute * nf_tables: nft_compat: private data of target and matches in contiguous area * nf_tables: validate hooks for compat match/target * nf_tables: nft_compat: release cached matches/targets * nf_tables: x_tables support as a compile time option * nf_tables: fix alias for xtables over nftables module * nf_tables: add packet and byte counters per chain * nf_tables: fix per-chain counter stats if no counters are passed * nf_tables: don't bump chain stats * nf_tables: add protocol and flags for xtables over nf_tables * nf_tables: add ip[6]t_entry emulation * nf_tables: move specific layer 3 compat code to nf_tables_ipv[4|6] * nf_tables: support 32bits-64bits x_tables compat * nf_tables: fix compilation if CONFIG_COMPAT is disabled From Patrick McHardy: * nf_tables: move policy to struct nft_base_chain * nf_tables: send notifications for base chain policy changes From Alexander Primak: * nf_tables: remove the duplicate NF_INET_LOCAL_OUT From Nicolas Dichtel: * nf_tables: fix compilation when nf-netlink is a module Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>