Commit Graph

410 Commits

Author SHA1 Message Date
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
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>
2019-06-19 17:09:55 +02:00
Florian Westphal 2c82c7e724 netfilter: nf_tables: fix oops during rule dump
We can oops in nf_tables_fill_rule_info().

Its not possible to fetch previous element in rcu-protected lists
when deletions are not prevented somehow: list_del_rcu poisons
the ->prev pointer value.

Before rcu-conversion this was safe as dump operations did hold
nfnetlink mutex.

Pass previous rule as argument, obtained by keeping a pointer to
the previous rule during traversal.

Fixes: d9adf22a29 ("netfilter: nf_tables: use call_rcu in netlink dumps")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-05-20 19:45:23 +02:00
David S. Miller 3ebb41bf47 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Postpone chain policy update to drop after transaction is complete,
   from Florian Westphal.

2) Add entry to flowtable after confirmation to fix UDP flows with
   packets going in one single direction.

3) Reference count leak in dst object, from Taehee Yoo.

4) Check for TTL field in flowtable datapath, from Taehee Yoo.

5) Fix h323 conntrack helper due to incorrect boundary check,
   from Jakub Jankowski.

6) Fix incorrect rcu dereference when fetching basechain stats,
   from Florian Westphal.

7) Missing error check when adding new entries to flowtable,
   from Taehee Yoo.

8) Use version field in nfnetlink message to honor the nfgen_family
   field, from Kristian Evensen.

9) Remove incorrect configuration check for CONFIG_NF_CONNTRACK_IPV6,
   from Subash Abhinov Kasiviswanathan.

10) Prevent dying entries from being added to the flowtable,
    from Taehee Yoo.

11) Don't hit WARN_ON() with malformed blob in ebtables with
    trailing data after last rule, reported by syzbot, patch
    from Florian Westphal.

12) Remove NFT_CT_TIMEOUT enumeration, never used in the kernel
    code.

13) Fix incorrect definition for NFT_LOGLEVEL_MAX, from Florian
    Westphal.

This batch comes with a conflict that can be fixed with this patch:

diff --cc include/uapi/linux/netfilter/nf_tables.h
index 7bdb234f3d8c,f0cf7b0f4f35..505393c6e959
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@@ -966,6 -966,8 +966,7 @@@ enum nft_socket_keys
   * @NFT_CT_DST_IP: conntrack layer 3 protocol destination (IPv4 address)
   * @NFT_CT_SRC_IP6: conntrack layer 3 protocol source (IPv6 address)
   * @NFT_CT_DST_IP6: conntrack layer 3 protocol destination (IPv6 address)
 - * @NFT_CT_TIMEOUT: connection tracking timeout policy assigned to conntrack
+  * @NFT_CT_ID: conntrack id
   */
  enum nft_ct_keys {
  	NFT_CT_STATE,
@@@ -991,6 -993,8 +992,7 @@@
  	NFT_CT_DST_IP,
  	NFT_CT_SRC_IP6,
  	NFT_CT_DST_IP6,
 -	NFT_CT_TIMEOUT,
+ 	NFT_CT_ID,
  	__NFT_CT_MAX
  };
  #define NFT_CT_MAX		(__NFT_CT_MAX - 1)

That replaces the unused NFT_CT_TIMEOUT definition by NFT_CT_ID. If you prefer,
I can also solve this conflict here, just let me know.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-13 08:55:15 -07:00
Florian Westphal edbd82c5fb netfilter: nf_tables: fix base chain stat rcu_dereference usage
Following splat gets triggered when nfnetlink monitor is running while
xtables-nft selftests are running:

net/netfilter/nf_tables_api.c:1272 suspicious rcu_dereference_check() usage!
other info that might help us debug this:

1 lock held by xtables-nft-mul/27006:
 #0: 00000000e0f85be9 (&net->nft.commit_mutex){+.+.}, at: nf_tables_valid_genid+0x1a/0x50
Call Trace:
 nf_tables_fill_chain_info.isra.45+0x6cc/0x6e0
 nf_tables_chain_notify+0xf8/0x1a0
 nf_tables_commit+0x165c/0x1740

nf_tables_fill_chain_info() can be called both from dumps (rcu read locked)
or from the transaction path if a userspace process subscribed to nftables
notifications.

In the 'table dump' case, rcu_access_pointer() cannot be used: We do not
hold transaction mutex so the pointer can be NULLed right after the check.
Just unconditionally fetch the value, then have the helper return
immediately if its NULL.

In the notification case we don't hold the rcu read lock, but updates are
prevented due to transaction mutex. Use rcu_dereference_check() to make lockdep
aware of this.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-05-06 00:36:29 +02:00
Florian Westphal 66293c46c9 netfilter: nf_tables: delay chain policy update until transaction is complete
When we process a long ruleset of the form

chain input {
   type filter hook input priority filter; policy drop;
   ...
}

Then the base chain gets registered early on, we then continue to
process/validate the next messages coming in the same transaction.

Problem is that if the base chain policy is 'drop', it will take effect
immediately, which causes all traffic to get blocked until the
transaction completes or is aborted.

Fix this by deferring the policy until the transaction has been
processed and all of the rules have been flagged as active.

Reported-by: Jann Haber <jann.haber@selfnet.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-30 13:47:32 +02:00
Johannes Berg 8cb081746c netlink: make validation more configurable for future strictness
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>
2019-04-27 17:07:21 -04:00
Michal Kubecek ae0be8de9a netlink: make nla_nest_start() add NLA_F_NESTED flag
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:03:44 -04:00
David S. Miller 8b44836583 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two easy cases of overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-25 23:52:29 -04:00
Dan Carpenter 33d1c01817 netfilter: nf_tables: prevent shift wrap in nft_chain_parse_hook()
I believe that "hook->num" can be up to UINT_MAX.  Shifting more than
31 bits would is undefined in C but in practice it would lead to shift
wrapping.  That would lead to an array overflow in nf_tables_addchain():

	ops->hook       = hook.type->hooks[ops->hooknum];

Fixes: fe19c04ca1 ("netfilter: nf_tables: remove nhooks field from struct nft_af_info")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-15 07:31:50 +02:00
Florian Westphal 3b0a081db1 netfilter: make two functions static
They have no external callers anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-08 23:28:33 +02:00
Florian Westphal c1deb065cf netfilter: nf_tables: merge route type into core
very little code, so it really doesn't make sense to have extra
modules or even a kconfig knob for this.

Merge them and make functionality available unconditionally.
The merge makes inet family route support trivial, so add it
as well here.

Before:
   text	   data	    bss	    dec	    hex	filename
    835	    832	      0	   1667	    683 nft_chain_route_ipv4.ko
    870	    832	      0	   1702	    6a6	nft_chain_route_ipv6.ko
 111568	   2556	    529	 114653	  1bfdd	nf_tables.ko

After:
   text	   data	    bss	    dec	    hex	filename
 113133	   2556	    529	 116218	  1c5fa	nf_tables.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-08 23:01:42 +02:00
Colin Ian King f7e840ee4d netfilter: nf_tables: remove unused parameter ctx
Function nf_tables_set_desc_parse parameter ctx is not being used
so remove it as it is redundant.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-08 22:56:52 +02:00
Li RongQing 3b15d09f7e time: Introduce jiffies64_to_msecs()
there is a similar helper in net/netfilter/nf_tables_api.c,
this maybe become a common request someday, so move it to
time.c

Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-08 22:56:14 +02:00
NeilBrown 8f0db01800 rhashtable: use bit_spin_locks to protect hash bucket.
This patch changes rhashtables to use a bit_spin_lock on BIT(1) of the
bucket pointer to lock the hash chain for that bucket.

The benefits of a bit spin_lock are:
 - no need to allocate a separate array of locks.
 - no need to have a configuration option to guide the
   choice of the size of this array
 - locking cost is often a single test-and-set in a cache line
   that will have to be loaded anyway.  When inserting at, or removing
   from, the head of the chain, the unlock is free - writing the new
   address in the bucket head implicitly clears the lock bit.
   For __rhashtable_insert_fast() we ensure this always happens
   when adding a new key.
 - even when lockings costs 2 updates (lock and unlock), they are
   in a cacheline that needs to be read anyway.

The cost of using a bit spin_lock is a little bit of code complexity,
which I think is quite manageable.

Bit spin_locks are sometimes inappropriate because they are not fair -
if multiple CPUs repeatedly contend of the same lock, one CPU can
easily be starved.  This is not a credible situation with rhashtable.
Multiple CPUs may want to repeatedly add or remove objects, but they
will typically do so at different buckets, so they will attempt to
acquire different locks.

As we have more bit-locks than we previously had spinlocks (by at
least a factor of two) we can expect slightly less contention to
go with the slightly better cache behavior and reduced memory
consumption.

To enhance type checking, a new struct is introduced to represent the
  pointer plus lock-bit
that is stored in the bucket-table.  This is "struct rhash_lock_head"
and is empty.  A pointer to this needs to be cast to either an
unsigned lock, or a "struct rhash_head *" to be useful.
Variables of this type are most often called "bkt".

Previously "pprev" would sometimes point to a bucket, and sometimes a
->next pointer in an rhash_head.  As these are now different types,
pprev is NULL when it would have pointed to the bucket. In that case,
'blk' is used, together with correct locking protocol.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-07 19:12:12 -07:00
Taehee Yoo b25a31bf0c netfilter: nf_tables: add missing ->release_ops() in error path of newrule()
->release_ops() callback releases resources and this is used in error path.
If nf_tables_newrule() fails after ->select_ops(), it should release
resources. but it can not call ->destroy() because that should be called
after ->init().
At this point, ->release_ops() should be used for releasing resources.

Test commands:
   modprobe -rv xt_tcpudp
   iptables-nft -I INPUT -m tcp   <-- error command
   lsmod

Result:
   Module                  Size  Used by
   xt_tcpudp              20480  2      <-- it should be 0

Fixes: b8e2040063 ("netfilter: nft_compat: use .release_ops and remove list of extension")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-20 08:32:58 +01:00
Florian Westphal b8b2749865 netfilter: nf_tables: return immediately on empty commit
When running 'nft flush ruleset' while no rules exist, we will increment
the generation counter and announce a new genid to userspace, yet
nothing had changed in the first place.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 20:01:20 +01:00
Pablo Neira Ayuso 3f3a390dbd netfilter: nf_tables: use-after-free in dynamic operations
Smatch reports:

       net/netfilter/nf_tables_api.c:2167 nf_tables_expr_destroy()
        error: dereferencing freed memory 'expr->ops'

net/netfilter/nf_tables_api.c
    2162 static void nf_tables_expr_destroy(const struct nft_ctx *ctx,
    2163                                   struct nft_expr *expr)
    2164 {
    2165        if (expr->ops->destroy)
    2166                expr->ops->destroy(ctx, expr);
                                                ^^^^
--> 2167        module_put(expr->ops->type->owner);
                           ^^^^^^^^^
    2168 }

Smatch says there are three functions which free expr->ops.

Fixes: b8e2040063 ("netfilter: nft_compat: use .release_ops and remove list of extension")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 13:19:49 +01:00
Pablo Neira Ayuso 273fe3f100 netfilter: nf_tables: bogus EBUSY when deleting set after flush
Set deletion after flush coming in the same batch results in EBUSY. Add
set use counter to track the number of references to this set from
rules. We cannot rely on the list of bindings for this since such list
is still populated from the preparation phase.

Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-11 13:19:24 +01:00
Pablo Neira Ayuso 40ba1d9b4d netfilter: nf_tables: fix set double-free in abort path
The abort path can cause a double-free of an anonymous set.
Added-and-to-be-aborted rule looks like this:

udp dport { 137, 138 } drop

The to-be-aborted transaction list looks like this:

newset
newsetelem
newsetelem
rule

This gets walked in reverse order, so first pass disables the rule, the
set elements, then the set.

After synchronize_rcu(), we then destroy those in same order: rule, set
element, set element, newset.

Problem is that the anonymous set has already been bound to the rule, so
the rule (lookup expression destructor) already frees the set, when then
cause use-after-free when trying to delete the elements from this set,
then try to free the set again when handling the newset expression.

Rule releases the bound set in first place from the abort path, this
causes the use-after-free on set element removal when undoing the new
element transactions. To handle this, skip new element transaction if
set is bound from the abort path.

This is still causes the use-after-free on set element removal.  To
handle this, remove transaction from the list when the set is already
bound.

Joint work with Florian Westphal.

Fixes: f6ac858589 ("netfilter: nf_tables: unbind set in rule from commit path")
Bugzilla: https://bugzilla.netfilter.org/show_bug.cgi?id=1325
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-03-08 16:41:18 +01:00
Pablo Neira Ayuso b8e2040063 netfilter: nft_compat: use .release_ops and remove list of extension
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>
2019-02-27 10:41:24 +01:00
David S. Miller 375ca548f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two easily resolvable overlapping change conflicts, one in
TCP and one in the eBPF verifier.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-20 00:34:07 -08:00
David S. Miller 8bbed40f10 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for you net-next
tree:

1) Missing NFTA_RULE_POSITION_ID netlink attribute validation,
   from Phil Sutter.

2) Restrict matching on tunnel metadata to rx/tx path, from wenxu.

3) Avoid indirect calls for IPV6=y, from Florian Westphal.

4) Add two indirections to prepare merger of IPV4 and IPV6 nat
   modules, from Florian Westphal.

5) Broken indentation in ctnetlink, from Colin Ian King.

6) Patches to use struct_size() from netfilter and IPVS,
   from Gustavo A. R. Silva.

7) Display kernel splat only once in case of racing to confirm
   conntrack from bridge plus nfqueue setups, from Chieh-Min Wang.

8) Skip checksum validation for layer 4 protocols that don't need it,
   patch from Alin Nastac.

9) Sparse warning due to symbol that should be static in CLUSTERIP,
   from Wei Yongjun.

10) Add new toggle to disable SDP payload translation when media
    endpoint is reachable though the same interface as the signalling
    peer, from Alin Nastac.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-18 11:38:30 -08:00
Pablo Neira Ayuso 23b7ca4f74 netfilter: nf_tables: fix flush after rule deletion in the same batch
Flush after rule deletion bogusly hits -ENOENT. Skip rules that have
been already from nft_delrule_by_chain() which is always called from the
flush path.

Fixes: cf9dc09d09 ("netfilter: nf_tables: fix missing rules flushing per table")
Reported-by: Phil Sutter <phil@nwl.cc>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-02-15 15:32:32 +01:00
David S. Miller a655fe9f19 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
An ipvlan bug fix in 'net' conflicted with the abstraction away
of the IPV6 specific support in 'net-next'.

Similarly, a bug fix for mlx5 in 'net' conflicted with the flow
action conversion in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-08 15:00:17 -08:00
Pablo Neira Ayuso f6ac858589 netfilter: nf_tables: unbind set in rule from commit path
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: cd5125d8f5 ("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>
2019-02-04 17:29:17 +01:00
Florian Westphal 0604628bb0 netfilter: nf_tables: add NFTA_RULE_POSITION_ID to nla_policy
Fixes: 75dd48e2e4 ("netfilter: nf_tables: Support RULE_ID reference in new rule")
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-29 16:59:06 +01:00
David S. Miller 343917b410 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for your net-next tree:

1) Introduce a hashtable to speed up object lookups, from Florian Westphal.

2) Make direct calls to built-in extension, also from Florian.

3) Call helper before confirming the conntrack as it used to be originally,
   from Florian.

4) Call request_module() to autoload br_netfilter when physdev is used
   to relax the dependency, also from Florian.

5) Allow to insert rules at a given position ID that is internal to the
   batch, from Phil Sutter.

6) Several patches to replace conntrack indirections by direct calls,
   and to reduce modularization, from Florian. This also includes
   several follow up patches to deal with minor fallout from this
   rework.

7) Use RCU from conntrack gre helper, from Florian.

8) GRE conntrack module becomes built-in into nf_conntrack, from Florian.

9) Replace nf_ct_invert_tuplepr() by calls to nf_ct_invert_tuple(),
   from Florian.

10) Unify sysctl handling at the core of nf_conntrack, from Florian.

11) Provide modparam to register conntrack hooks.

12) Allow to match on the interface kind string, from wenxu.

13) Remove several exported symbols, not required anymore now after
    a bit of de-modulatization work has been done, from Florian.

14) Remove built-in map support in the hash extension, this can be
    done with the existing userspace infrastructure, from laura.

15) Remove indirection to calculate checksums in IPVS, from Matteo Croce.

16) Use call wrappers for indirection in IPVS, also from Matteo.

17) Remove superfluous __percpu parameter in nft_counter, patch from
    Luc Van Oostenryck.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-28 17:34:38 -08:00
Phil Sutter 75dd48e2e4 netfilter: nf_tables: Support RULE_ID reference in new rule
To allow for a batch to contain rules in arbitrary ordering, introduce
NFTA_RULE_POSITION_ID attribute which works just like NFTA_RULE_POSITION
but contains the ID of another rule within the same batch. This helps
iptables-nft-restore handling dumps with mixed insert/append commands
correctly.

Note that NFTA_RULE_POSITION takes precedence over
NFTA_RULE_POSITION_ID, so if the former is present, the latter is
ignored.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal 4d44175aa5 netfilter: nf_tables: handle nft_object lookups via rhltable
Instead of linear search, use rhlist interface to look up the objects.
This fixes rulesets with thousands of named objects (quota, counters and
the like).

We only use a single table for this and consider the address of the
table we're doing the lookup in as a part of the key.

This reduces restore time of a sample ruleset with ~20k named counters
from 37 seconds to 0.8 seconds.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:33 +01:00
Florian Westphal d152159b89 netfilter: nf_tables: prepare nft_object for lookups via hashtable
Add a 'key' structure for object, so we can look them up by name + table
combination (the name can be the same in each table).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-18 15:02:32 +01:00
Pablo Neira Ayuso 715849ab31 netfilter: nf_tables: selective rule dump needs table to be specified
Table needs to be specified for selective rule dumps per chain.

Fixes: 241faeceb8 ("netfilter: nf_tables: Speed up selective rule dumps")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-08 23:31:18 +01:00
Taehee Yoo b91d903688 netfilter: nf_tables: fix leaking object reference count
There is no code that decreases the reference count of stateful objects
in error path of the nft_add_set_elem(). this causes a leak of reference
count of stateful objects.

Test commands:
   $nft add table ip filter
   $nft add counter ip filter c1
   $nft add map ip filter m1 { type ipv4_addr : counter \;}
   $nft add element ip filter m1 { 1 : c1 }
   $nft add element ip filter m1 { 1 : c1 }
   $nft delete element ip filter m1 { 1 }
   $nft delete counter ip filter c1

Result:
   Error: Could not process rule: Device or resource busy
   delete counter ip filter c1
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

At the second 'nft add element ip filter m1 { 1 : c1 }', the reference
count of the 'c1' is increased then it tries to insert into the 'm1'. but
the 'm1' already has same element so it returns -EEXIST.
But it doesn't decrease the reference count of the 'c1' in the error path.
Due to a leak of the reference count of the 'c1', the 'c1' can't be
removed by 'nft delete counter ip filter c1'.

Fixes: 8aeff920dc ("netfilter: nf_tables: add stateful object reference to set elements")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-08 23:31:17 +01:00
Phil Sutter 310529e663 netfilter: nf_tables: Fix for endless loop when dumping ruleset
__nf_tables_dump_rules() stores the current idx value into cb->args[0]
before returning to caller. With multiple chains present, cb->args[0] is
therefore updated after each chain's rules have been traversed. This
though causes the final nf_tables_dump_rules() run (which should return
an skb->len of zero since no rules are left to dump) to continue dumping
rules for each but the first chain. Fix this by moving the cb->args[0]
update to nf_tables_dump_rules().

With no final action to be performed anymore in
__nf_tables_dump_rules(), drop 'out_unfinished' jump label and 'rc'
variable - instead return the appropriate value directly.

Fixes: 241faeceb8 ("netfilter: nf_tables: Speed up selective rule dumps")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-01-08 23:01:13 +01:00
Kangjie Lu eb8950861c netfilter: nf_tables: fix a missing check of nla_put_failure
If nla_nest_start() may fail. The fix checks its return value and goes
to nla_put_failure if it fails.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-29 02:44:51 +01:00
David S. Miller c3e5336925 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Support for destination MAC in ipset, from Stefano Brivio.

2) Disallow all-zeroes MAC address in ipset, also from Stefano.

3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands,
   introduce protocol version number 7, from Jozsef Kadlecsik.
   A follow up patch to fix ip_set_byindex() is also included
   in this batch.

4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi.

5) Statify nf_flow_table_iterate(), from Taehee Yoo.

6) Use nf_flow_table_iterate() to simplify garbage collection in
   nf_flow_table logic, also from Taehee Yoo.

7) Don't use _bh variants of call_rcu(), rcu_barrier() and
   synchronize_rcu_bh() in Netfilter, from Paul E. McKenney.

8) Remove NFC_* cache definition from the old caching
   infrastructure.

9) Remove layer 4 port rover in NAT helpers, use random port
   instead, from Florian Westphal.

10) Use strscpy() in ipset, from Qian Cai.

11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that
    random port is allocated by default, from Xiaozhou Liu.

12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal.

13) Limit port allocation selection routine in NAT to avoid
    softlockup splats when most ports are in use, from Florian.

14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl()
    from Yafang Shao.

15) Direct call to nf_nat_l4proto_unique_tuple() instead of
    indirection, from Florian Westphal.

16) Several patches to remove all layer 4 NAT indirections,
    remove nf_nat_l4proto struct, from Florian Westphal.

17) Fix RTP/RTCP source port translation when SNAT is in place,
    from Alin Nastac.

18) Selective rule dump per chain, from Phil Sutter.

19) Revisit CLUSTERIP target, this includes a deadlock fix from
    netns path, sleep in atomic, remove bogus WARN_ON_ONCE()
    and disallow mismatching IP address and MAC address.
    Patchset from Taehee Yoo.

20) Update UDP timeout to stream after 2 seconds, from Florian.

21) Shrink UDP established timeout to 120 seconds like TCP timewait.

22) Sysctl knobs to set GRE timeouts, from Yafang Shao.

23) Move seq_print_acct() to conntrack core file, from Florian.

24) Add enum for conntrack sysctl knobs, also from Florian.

25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events
    and nf_conntrack_timestamp knobs in the core, from Florian Westphal.
    As a side effect, shrink netns_ct structure by removing obsolete
    sysctl anchors, also from Florian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 18:20:26 -08:00
Phil Sutter 241faeceb8 netfilter: nf_tables: Speed up selective rule dumps
If just a table name was given, nf_tables_dump_rules() continued over
the list of tables even after a match was found. The simple fix is to
exit the loop if it reached the bottom and ctx->table was not NULL.

When iterating over the table's chains, the same problem as above
existed. But worse than that, if a chain name was given the hash table
wasn't used to find the corresponding chain. Fix this by introducing a
helper function iterating over a chain's rules (and taking care of the
cb->args handling), then introduce a shortcut to it if a chain name was
given.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-18 00:08:53 +01:00
Taehee Yoo 4c05ec4738 netfilter: nf_tables: fix suspicious RCU usage in nft_chain_stats_replace()
basechain->stats is rcu protected data which is updated from
nft_chain_stats_replace(). This function is executed from the commit
phase which holds the pernet nf_tables commit mutex - not the global
nfnetlink subsystem mutex.

Test commands to reproduce the problem are:
   %iptables-nft -I INPUT
   %iptables-nft -Z
   %iptables-nft -Z

This patch uses RCU calls to handle basechain->stats updates to fix a
splat that looks like:

[89279.358755] =============================
[89279.363656] WARNING: suspicious RCU usage
[89279.368458] 4.20.0-rc2+ #44 Tainted: G        W    L
[89279.374661] -----------------------------
[89279.379542] net/netfilter/nf_tables_api.c:1404 suspicious rcu_dereference_protected() usage!
[...]
[89279.406556] 1 lock held by iptables-nft/5225:
[89279.411728]  #0: 00000000bf45a000 (&net->nft.commit_mutex){+.+.}, at: nf_tables_valid_genid+0x1f/0x70 [nf_tables]
[89279.424022] stack backtrace:
[89279.429236] CPU: 0 PID: 5225 Comm: iptables-nft Tainted: G        W    L    4.20.0-rc2+ #44
[89279.430135] Call Trace:
[89279.430135]  dump_stack+0xc9/0x16b
[89279.430135]  ? show_regs_print_info+0x5/0x5
[89279.430135]  ? lockdep_rcu_suspicious+0x117/0x160
[89279.430135]  nft_chain_commit_update+0x4ea/0x640 [nf_tables]
[89279.430135]  ? sched_clock_local+0xd4/0x140
[89279.430135]  ? check_flags.part.35+0x440/0x440
[89279.430135]  ? __rhashtable_remove_fast.constprop.67+0xec0/0xec0 [nf_tables]
[89279.430135]  ? sched_clock_cpu+0x126/0x170
[89279.430135]  ? find_held_lock+0x39/0x1c0
[89279.430135]  ? hlock_class+0x140/0x140
[89279.430135]  ? is_bpf_text_address+0x5/0xf0
[89279.430135]  ? check_flags.part.35+0x440/0x440
[89279.430135]  ? __lock_is_held+0xb4/0x140
[89279.430135]  nf_tables_commit+0x2555/0x39c0 [nf_tables]

Fixes: f102d66b33 ("netfilter: nf_tables: use dedicated mutex to guard transactions")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-12-04 01:37:13 +01:00
Taehee Yoo ca08987885 netfilter: nf_tables: deactivate expressions in rule replecement routine
There is no expression deactivation call from the rule replacement path,
hence, chain counter is not decremented. A few steps to reproduce the
problem:

   %nft add table ip filter
   %nft add chain ip filter c1
   %nft add chain ip filter c1
   %nft add rule ip filter c1 jump c2
   %nft replace rule ip filter c1 handle 3 accept
   %nft flush ruleset

<jump c2> expression means immediate NFT_JUMP to chain c2.
Reference count of chain c2 is increased when the rule is added.

When rule is deleted or replaced, the reference counter of c2 should be
decreased via nft_rule_expr_deactivate() which calls
nft_immediate_deactivate().

Splat looks like:
[  214.396453] WARNING: CPU: 1 PID: 21 at net/netfilter/nf_tables_api.c:1432 nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables]
[  214.398983] Modules linked in: nf_tables nfnetlink
[  214.398983] CPU: 1 PID: 21 Comm: kworker/1:1 Not tainted 4.20.0-rc2+ #44
[  214.398983] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
[  214.398983] RIP: 0010:nf_tables_chain_destroy.isra.38+0x2f9/0x3a0 [nf_tables]
[  214.398983] Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 8e 00 00 00 48 8b 7b 58 e8 e1 2c 4e c6 48 89 df e8 d9 2c 4e c6 eb 9a <0f> 0b eb 96 0f 0b e9 7e fe ff ff e8 a7 7e 4e c6 e9 a4 fe ff ff e8
[  214.398983] RSP: 0018:ffff8881152874e8 EFLAGS: 00010202
[  214.398983] RAX: 0000000000000001 RBX: ffff88810ef9fc28 RCX: ffff8881152876f0
[  214.398983] RDX: dffffc0000000000 RSI: 1ffff11022a50ede RDI: ffff88810ef9fc78
[  214.398983] RBP: 1ffff11022a50e9d R08: 0000000080000000 R09: 0000000000000000
[  214.398983] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff11022a50eba
[  214.398983] R13: ffff888114446e08 R14: ffff8881152876f0 R15: ffffed1022a50ed6
[  214.398983] FS:  0000000000000000(0000) GS:ffff888116400000(0000) knlGS:0000000000000000
[  214.398983] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  214.398983] CR2: 00007fab9bb5f868 CR3: 000000012aa16000 CR4: 00000000001006e0
[  214.398983] Call Trace:
[  214.398983]  ? nf_tables_table_destroy.isra.37+0x100/0x100 [nf_tables]
[  214.398983]  ? __kasan_slab_free+0x145/0x180
[  214.398983]  ? nf_tables_trans_destroy_work+0x439/0x830 [nf_tables]
[  214.398983]  ? kfree+0xdb/0x280
[  214.398983]  nf_tables_trans_destroy_work+0x5f5/0x830 [nf_tables]
[ ... ]

Fixes: bb7b40aecb ("netfilter: nf_tables: bogus EBUSY in chain deletions")
Reported by: Christoph Anton Mitterer <calestyo@scientia.net>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914505
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201791
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-28 10:56:40 +01:00
Florian Westphal 29e3880109 netfilter: nf_tables: fix use-after-free when deleting compat expressions
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: 0ca743a559 ("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>
2018-11-13 09:57:33 +01:00
Florian Westphal 447750f281 netfilter: nf_tables: don't use position attribute on rule replacement
Its possible to set both HANDLE and POSITION when replacing a rule.
In this case, the rule at POSITION gets replaced using the
userspace-provided handle.  Rule handles are supposed to be generated
by the kernel only.

Duplicate handles should be harmless, however better disable this "feature"
by only checking for the POSITION attribute on insert operations.

Fixes: 5e94846686 ("netfilter: nf_tables: add insert operation")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-12 16:13:35 +01:00
Florian Westphal 0fb39bbe43 netfilter: nf_tables: don't skip inactive chains during update
There is no synchronization between packet path and the configuration plane.

The packet path uses two arrays with rules, one contains the current (active)
generation.  The other either contains the last (obsolete) generation or
the future one.

Consider:
cpu1               cpu2
                   nft_do_chain(c);
delete c
net->gen++;
                   genbit = !!net->gen;
                   rules = c->rg[genbit];

cpu1 ignores c when updating if c is not active anymore in the new
generation.

On cpu2, we now use rules from wrong generation, as c->rg[old]
contains the rules matching 'c' whereas c->rg[new] was not updated and
can even point to rules that have been free'd already, causing a crash.

To fix this, make sure that 'current' to the 'next' generation are
identical for chains that are going away so that c->rg[new] will just
use the matching rules even if genbit was incremented already.

Fixes: 0cbc06b3fa ("netfilter: nf_tables: remove synchronize_rcu in commit phase")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-12 16:13:35 +01:00
David S. Miller 807192deb8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree:

1) rbtree lookup from control plane returns the left-hand side element
   of the range when the interval end flag is set on.

2) osf extension is not supported from the input path, reject this from
   the control plane, from Fernando Fernandez Mancera.

3) xt_TEE is leaving output interface unset due to a recent incorrect
   netns rework, from Taehee Yoo.

4) xt_TEE allows to select an interface which does not belong to this
   netnamespace, from Taehee Yoo.

5) Zero private extension area in nft_compat, just like we do in x_tables,
   otherwise we leak kernel memory to userspace.

6) Missing .checkentry and .destroy entries in new DNAT extensions breaks
   it since we never load nf_conntrack dependencies, from Paolo Abeni.

7) Do not remove flowtable hook from netns exit path, the netdevice handler
   already deals with this, also from Taehee Yoo.

8) Only cleanup flowtable entries that reside in this netnamespace, also
   from Taehee Yoo.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 20:21:30 -07:00
Taehee Yoo b7f1a16d29 netfilter: nf_flow_table: remove flowtable hook flush routine in netns exit routine
When device is unregistered, flowtable flush routine is called
by notifier_call(nf_tables_flowtable_event). and exit callback of
nftables pernet_operation(nf_tables_exit_net) also has flowtable flush
routine. but when network namespace is destroyed, both notifier_call
and pernet_operation are called. hence flowtable flush routine in
pernet_operation is unnecessary.

test commands:
   %ip netns add vm1
   %ip netns exec vm1 nft add table ip filter
   %ip netns exec vm1 nft add flowtable ip filter w \
	{ hook ingress priority 0\; devices = { lo }\; }
   %ip netns del vm1

splat looks like:
[  265.187019] WARNING: CPU: 0 PID: 87 at net/netfilter/core.c:309 nf_hook_entry_head+0xc7/0xf0
[  265.187112] Modules linked in: nf_flow_table_ipv4 nf_flow_table nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink ip_tables x_tables
[  265.187390] CPU: 0 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc3+ #5
[  265.187453] Workqueue: netns cleanup_net
[  265.187514] RIP: 0010:nf_hook_entry_head+0xc7/0xf0
[  265.187546] Code: 8d 81 68 03 00 00 5b c3 89 d0 83 fa 04 48 8d 84 c7 e8 11 00 00 76 81 0f 0b 31 c0 e9 78 ff ff ff 0f 0b 48 83 c4 08 31 c0 5b c3 <0f> 0b 31 c0 e9 65 ff ff ff 0f 0b 31 c0 e9 5c ff ff ff 48 89 0c 24
[  265.187573] RSP: 0018:ffff88011546f098 EFLAGS: 00010246
[  265.187624] RAX: ffffffff8d90e135 RBX: 1ffff10022a8de1c RCX: 0000000000000000
[  265.187645] RDX: 0000000000000000 RSI: 0000000000000005 RDI: ffff880116298040
[  265.187645] RBP: ffff88010ea4c1a8 R08: 0000000000000000 R09: 0000000000000000
[  265.187645] R10: ffff88011546f1d8 R11: ffffed0022c532c1 R12: ffff88010ea4c1d0
[  265.187645] R13: 0000000000000005 R14: dffffc0000000000 R15: ffff88010ea4c1c4
[  265.187645] FS:  0000000000000000(0000) GS:ffff88011b200000(0000) knlGS:0000000000000000
[  265.187645] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  265.187645] CR2: 00007fdfb8d00000 CR3: 0000000057a16000 CR4: 00000000001006f0
[  265.187645] Call Trace:
[  265.187645]  __nf_unregister_net_hook+0xca/0x5d0
[  265.187645]  ? nf_hook_entries_free.part.3+0x80/0x80
[  265.187645]  ? save_trace+0x300/0x300
[  265.187645]  nf_unregister_net_hooks+0x2e/0x40
[  265.187645]  nf_tables_exit_net+0x479/0x1340 [nf_tables]
[  265.187645]  ? find_held_lock+0x39/0x1c0
[  265.187645]  ? nf_tables_abort+0x30/0x30 [nf_tables]
[  265.187645]  ? inet_frag_destroy_rcu+0xd0/0xd0
[  265.187645]  ? trace_hardirqs_on+0x93/0x210
[  265.187645]  ? __bpf_trace_preemptirq_template+0x10/0x10
[  265.187645]  ? inet_frag_destroy_rcu+0xd0/0xd0
[  265.187645]  ? inet_frag_destroy_rcu+0xd0/0xd0
[  265.187645]  ? __mutex_unlock_slowpath+0x17f/0x740
[  265.187645]  ? wait_for_completion+0x710/0x710
[  265.187645]  ? bucket_table_free+0xb2/0x1f0
[  265.187645]  ? nested_table_free+0x130/0x130
[  265.187645]  ? __lock_is_held+0xb4/0x140
[  265.187645]  ops_exit_list.isra.10+0x94/0x140
[  265.187645]  cleanup_net+0x45b/0x900
[ ... ]

This WARNING means that hook unregisteration is failed because
all flowtables hooks are already unregistered by notifier_call.

Network namespace exit routine guarantees that all devices will be
unregistered first. then, other exit callbacks of pernet_operations
are called. so that removing flowtable flush routine in exit callback of
pernet_operation(nf_tables_exit_net) doesn't make flowtable leak.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-10-19 12:35:47 +02:00
Florian Westphal fa5950e498 netfilter: nf_tables: avoid BUG_ON usage
None of these spots really needs to crash the kernel.
In one two cases we can jsut report error to userspace, in the other
cases we can just use WARN_ON (and leak memory instead).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-17 16:11:12 +02:00
Florian Westphal 0935d55884 netfilter: nf_tables: asynchronous release
Release the committed transaction log from a work queue, moving
expensive synchronize_rcu out of the locked section and providing
opportunity to batch this.

On my test machine this cuts runtime of nft-test.py in half.
Based on earlier patch from Pablo Neira Ayuso.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-17 11:40:07 +02:00
Florian Westphal 0ef235c717 netfilter: nf_tables: warn when expr implements only one of activate/deactivate
->destroy is only allowed to free data, or do other cleanups that do not
have side effects on other state, such as visibility to other netlink
requests.

Such things need to be done in ->deactivate.
As a transaction can fail, we need to make sure we can undo such
operations, therefore ->activate() has to be provided too.

So print a warning and refuse registration if expr->ops provides
only one of the two operations.

v2: fix nft_expr_check_ops to not repeat same check twice (Jones Desougi)

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-17 11:40:06 +02:00
Florian Westphal cd5125d8f5 netfilter: nf_tables: split set destruction in deactivate and destroy phase
Splits unbind_set into destroy_set and unbinding operation.

Unbinding removes set from lists (so new transaction would not
find it anymore) but keeps memory allocated (so packet path continues
to work).

Rebind function is added to allow unrolling in case transaction
that wants to remove set is aborted.

Destroy function is added to free the memory, but this could occur
outside of transaction in the future.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-09-17 11:29:49 +02:00
Taehee Yoo 7acfda539c netfilter: nf_tables: release chain in flushing set
When element of verdict map is deleted, the delete routine should
release chain. however, flush element of verdict map routine doesn't
release chain.

test commands:
   %nft add table ip filter
   %nft add chain ip filter c1
   %nft add map ip filter map1 { type ipv4_addr : verdict \; }
   %nft add element ip filter map1 { 1 : jump c1 }
   %nft flush map ip filter map1
   %nft flush ruleset

splat looks like:
[ 4895.170899] kernel BUG at net/netfilter/nf_tables_api.c:1415!
[ 4895.178114] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 4895.178880] CPU: 0 PID: 1670 Comm: nft Not tainted 4.18.0+ #55
[ 4895.178880] RIP: 0010:nf_tables_chain_destroy.isra.28+0x39/0x220 [nf_tables]
[ 4895.178880] Code: fc ff df 53 48 89 fb 48 83 c7 50 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 09 3c 03 7f 05 e8 3e 4c 25 e1 8b 43 50 85 c0 74 02 <0f> 0b 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02
[ 4895.228342] RSP: 0018:ffff88010b98f4c0 EFLAGS: 00010202
[ 4895.234841] RAX: 0000000000000001 RBX: ffff8801131c6968 RCX: ffff8801146585b0
[ 4895.234841] RDX: 1ffff10022638d37 RSI: ffff8801191a9348 RDI: ffff8801131c69b8
[ 4895.234841] RBP: ffff8801146585a8 R08: 1ffff1002323526a R09: 0000000000000000
[ 4895.234841] R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000200
[ 4895.234841] R13: dead000000000100 R14: ffffffffa3638af8 R15: dffffc0000000000
[ 4895.234841] FS:  00007f6d188e6700(0000) GS:ffff88011b600000(0000) knlGS:0000000000000000
[ 4895.234841] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4895.234841] CR2: 00007ffe72b8df88 CR3: 000000010e2d4000 CR4: 00000000001006f0
[ 4895.234841] Call Trace:
[ 4895.234841]  nf_tables_commit+0x2704/0x2c70 [nf_tables]
[ 4895.234841]  ? nfnetlink_rcv_batch+0xa4f/0x11b0 [nfnetlink]
[ 4895.234841]  ? nf_tables_setelem_notify.constprop.48+0x1a0/0x1a0 [nf_tables]
[ 4895.323824]  ? __lock_is_held+0x9d/0x130
[ 4895.323824]  ? kasan_unpoison_shadow+0x30/0x40
[ 4895.333299]  ? kasan_kmalloc+0xa9/0xc0
[ 4895.333299]  ? kmem_cache_alloc_trace+0x2c0/0x310
[ 4895.333299]  ? nfnetlink_rcv_batch+0xa4f/0x11b0 [nfnetlink]
[ 4895.333299]  nfnetlink_rcv_batch+0xdb9/0x11b0 [nfnetlink]
[ 4895.333299]  ? debug_show_all_locks+0x290/0x290
[ 4895.333299]  ? nfnetlink_net_init+0x150/0x150 [nfnetlink]
[ 4895.333299]  ? sched_clock_cpu+0xe5/0x170
[ 4895.333299]  ? sched_clock_local+0xff/0x130
[ 4895.333299]  ? sched_clock_cpu+0xe5/0x170
[ 4895.333299]  ? find_held_lock+0x39/0x1b0
[ 4895.333299]  ? sched_clock_local+0xff/0x130
[ 4895.333299]  ? memset+0x1f/0x40
[ 4895.333299]  ? nla_parse+0x33/0x260
[ 4895.333299]  ? ns_capable_common+0x6e/0x110
[ 4895.333299]  nfnetlink_rcv+0x2c0/0x310 [nfnetlink]
[ ... ]

Fixes: 591054469b ("netfilter: nf_tables: revisit chain/object refcounting from elements")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-31 19:07:11 +02:00
Florian Westphal 6a48de0144 netfilter: nf_tables: don't prevent event handler from device cleanup on netns exit
When a netnsamespace exits, the nf_tables pernet_ops will remove all rules.
However, there is one caveat:

Base chains that register ingress hooks will cause use-after-free:
device is already gone at that point.

The device event handlers prevent this from happening:
netns exit synthesizes unregister events for all devices.

However, an improper fix for a race condition made the notifiers a no-op
in case they get called from netns exit path, so revert that part.

This is safe now as the previous patch fixed nf_tables pernet ops
and device notifier initialisation ordering.

Fixes: 0a2cf5ee43 ("netfilter: nf_tables: close race between netns exit and rmmod")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-16 19:37:03 +02:00
Florian Westphal d209df3e7f netfilter: nf_tables: fix register ordering
We must register nfnetlink ops last, as that exposes nf_tables to
userspace.  Without this, we could theoretically get nfnetlink request
before net->nft state has been initialized.

Fixes: 99633ab29b ("netfilter: nf_tables: complete net namespace support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-16 19:37:02 +02:00