Commit Graph

5945 Commits

Author SHA1 Message Date
Jeremy Sowden
a219cabada netfilter: nft_redir: correct value of inet type .maxattrs
[ Upstream commit 493924519b ]

`nft_redir_inet_type.maxattrs` was being set, presumably because of a
cut-and-paste error, to `NFTA_MASQ_MAX`, instead of `NFTA_REDIR_MAX`.

Fixes: 63ce3940f3 ("netfilter: nft_redir: add inet support")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:31:23 +01:00
Jeremy Sowden
de03d13017 netfilter: nft_redir: correct length for loading protocol registers
[ Upstream commit 1f617b6b4c ]

The values in the protocol registers are two bytes wide.  However, when
parsing the register loads, the code currently uses the larger 16-byte
size of a `union nf_inet_addr`.  Change it to use the (correct) size of
a `union nf_conntrack_man_proto` instead.

Fixes: d07db9884a ("netfilter: nf_tables: introduce nft_validate_register_load()")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:31:23 +01:00
Jeremy Sowden
d2a2ad64b9 netfilter: nft_masq: correct length for loading protocol registers
[ Upstream commit ec2c5917eb ]

The values in the protocol registers are two bytes wide.  However, when
parsing the register loads, the code currently uses the larger 16-byte
size of a `union nf_inet_addr`.  Change it to use the (correct) size of
a `union nf_conntrack_man_proto` instead.

Fixes: 8a6bf5da1a ("netfilter: nft_masq: support port range")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:31:23 +01:00
Jeremy Sowden
343fe451e6 netfilter: nft_nat: correct length for loading protocol registers
[ Upstream commit 068d82e75d ]

The values in the protocol registers are two bytes wide.  However, when
parsing the register loads, the code currently uses the larger 16-byte
size of a `union nf_inet_addr`.  Change it to use the (correct) size of
a `union nf_conntrack_man_proto` instead.

Fixes: d07db9884a ("netfilter: nf_tables: introduce nft_validate_register_load()")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:31:23 +01:00
Eric Dumazet
36bcbcaf01 netfilter: conntrack: adopt safer max chain length
[ Upstream commit c77737b736 ]

Customers using GKE 1.25 and 1.26 are facing conntrack issues
root caused to commit c9c3b6811f ("netfilter: conntrack: make
max chain length random").

Even if we assume Uniform Hashing, a bucket often reachs 8 chained
items while the load factor of the hash table is smaller than 0.5

With a limit of 16, we reach load factors of 3.
With a limit of 32, we reach load factors of 11.
With a limit of 40, we reach load factors of 15.
With a limit of 50, we reach load factors of 24.

This patch changes MIN_CHAINLEN to 50, to minimize risks.

Ideally, we could in the future add a cushion based on expected
load factor (2 * nf_conntrack_max / nf_conntrack_buckets),
because some setups might expect unusual values.

Fixes: c9c3b6811f ("netfilter: conntrack: make max chain length random")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-17 08:48:56 +01:00
Ivan Delalande
bef8cf77e2 netfilter: ctnetlink: revert to dumping mark regardless of event type
[ Upstream commit 9f7dd42f0d ]

It seems that change was unintentional, we have userspace code that
needs the mark while listening for events like REPLY, DESTROY, etc.
Also include 0-marks in requested dumps, as they were before that fix.

Fixes: 1feeae0715 ("netfilter: ctnetlink: fix compilation warning after data race fixes in ct mark")
Signed-off-by: Ivan Delalande <colona@arista.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-17 08:48:55 +01:00
Hangyu Hua
af41b3cd9a netfilter: ctnetlink: fix possible refcount leak in ctnetlink_create_conntrack()
[ Upstream commit ac4893980b ]

nf_ct_put() needs to be called to put the refcount got by
nf_conntrack_find_get() to avoid refcount leak when
nf_conntrack_hash_check_insert() fails.

Fixes: 7d367e0668 ("netfilter: ctnetlink: fix soft lockup when netlink adds new entries (v2)")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 13:57:27 +01:00
Pablo Neira Ayuso
ed1d288ec8 netfilter: nf_tables: allow to fetch set elements when table has an owner
[ Upstream commit 92f3e96d64 ]

NFT_MSG_GETSETELEM returns -EPERM when fetching set elements that belong
to table that has an owner. This results in empty set/map listing from
userspace.

Fixes: 6001a930ce ("netfilter: nftables: introduce table ownership")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 13:57:26 +01:00
Alok Tiwari
2493966c87 netfilter: nf_tables: NULL pointer dereference in nf_tables_updobj()
[ Upstream commit dac7f50a45 ]

static analyzer detect null pointer dereference case for 'type'
function __nft_obj_type_get() can return NULL value which require to handle
if type is NULL pointer return -ENOENT.

This is a theoretical issue, since an existing object has a type, but
better add this failsafe check.

Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10 09:39:49 +01:00
Florian Westphal
9a1d92cbea netfilter: nft_tproxy: restrict to prerouting hook
commit 18bbc32133 upstream.

TPROXY is only allowed from prerouting, but nft_tproxy doesn't check this.
This fixes a crash (null dereference) when using tproxy from e.g. output.

Fixes: 4ed8eb6570 ("netfilter: nf_tables: Add native tproxy support")
Reported-by: Shell Chen <xierch@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Qingfang DENG <dqfext@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22 12:57:05 +01:00
Sriram Yagnaraman
033636b322 netfilter: conntrack: unify established states for SCTP paths
commit a44b765148 upstream.

An SCTP endpoint can start an association through a path and tear it
down over another one. That means the initial path will not see the
shutdown sequence, and the conntrack entry will remain in ESTABLISHED
state for 5 days.

By merging the HEARTBEAT_ACKED and ESTABLISHED states into one
ESTABLISHED state, there remains no difference between a primary or
secondary path. The timeout for the merged ESTABLISHED state is set to
210 seconds (hb_interval * max_path_retrans + rto_max). So, even if a
path doesn't see the shutdown sequence, it will expire in a reasonable
amount of time.

With this change in place, there is now more than one state from which
we can transition to ESTABLISHED, COOKIE_ECHOED and HEARTBEAT_SENT, so
handle the setting of ASSURED bit whenever a state change has happened
and the new state is ESTABLISHED. Removed the check for dir==REPLY since
the transition to ESTABLISHED can happen only in the reply direction.

Fixes: 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.")
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-01 08:27:30 +01:00
Sriram Yagnaraman
9df5ab02c6 netfilter: conntrack: fix vtag checks for ABORT/SHUTDOWN_COMPLETE
[ Upstream commit a9993591fa ]

RFC 9260, Sec 8.5.1 states that for ABORT/SHUTDOWN_COMPLETE, the chunk
MUST be accepted if the vtag of the packet matches its own tag and the
T bit is not set OR if it is set to its peer's vtag and the T bit is set
in chunk flags. Otherwise the packet MUST be silently dropped.

Update vtag verification for ABORT/SHUTDOWN_COMPLETE based on the above
description.

Fixes: 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.")
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:27:27 +01:00
Pablo Neira Ayuso
8a13595600 netfilter: nft_set_rbtree: skip elements in transaction from garbage collection
[ Upstream commit 5d235d6ce7 ]

Skip interference with an ongoing transaction, do not perform garbage
collection on inactive elements. Reset annotated previous end interval
if the expired element is marked as busy (control plane removed the
element right before expiration).

Fixes: 8d8540c4f5 ("netfilter: nft_set_rbtree: add timeout support")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:27:26 +01:00
Pablo Neira Ayuso
2bf1435fa1 netfilter: nft_set_rbtree: Switch to node list walk for overlap detection
[ Upstream commit c9e6978e27 ]

...instead of a tree descent, which became overly complicated in an
attempt to cover cases where expired or inactive elements would affect
comparisons with the new element being inserted.

Further, it turned out that it's probably impossible to cover all those
cases, as inactive nodes might entirely hide subtrees consisting of a
complete interval plus a node that makes the current insertion not
overlap.

To speed up the overlap check, descent the tree to find a greater
element that is closer to the key value to insert. Then walk down the
node list for overlap detection. Starting the overlap check from
rb_first() unconditionally is slow, it takes 10 times longer due to the
full linear traversal of the list.

Moreover, perform garbage collection of expired elements when walking
down the node list to avoid bogus overlap reports.

For the insertion operation itself, this essentially reverts back to the
implementation before commit 7c84d41416 ("netfilter: nft_set_rbtree:
Detect partial overlaps on insertion"), except that cases of complete
overlap are already handled in the overlap detection phase itself, which
slightly simplifies the loop to find the insertion point.

Based on initial patch from Stefano Brivio, including text from the
original patch description too.

Fixes: 7c84d41416 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01 08:27:26 +01:00
Gavrilov Ilia
511cf17b24 netfilter: ipset: Fix overflow before widen in the bitmap_ip_create() function.
commit 9ea4b476ce upstream.

When first_ip is 0, last_ip is 0xFFFFFFFF, and netmask is 31, the value of
an arithmetic expression 2 << (netmask - mask_bits - 1) is subject
to overflow due to a failure casting operands to a larger data type
before performing the arithmetic.

Note that it's harmless since the value will be checked at the next step.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Fixes: b9fed74818 ("netfilter: ipset: Check and reject crazy /0 input parameters")
Signed-off-by: Ilia.Gavrilov <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:48:52 +01:00
Pablo Neira Ayuso
a8acfe2c6f netfilter: nft_payload: incorrect arithmetics when fetching VLAN header bits
commit 696e1a48b1 upstream.

If the offset + length goes over the ethernet + vlan header, then the
length is adjusted to copy the bytes that are within the boundaries of
the vlan_ethhdr scratchpad area. The remaining bytes beyond ethernet +
vlan header are copied directly from the skbuff data area.

Fix incorrect arithmetic operator: subtract, not add, the size of the
vlan header in case of double-tagged packets to adjust the length
accordingly to address CVE-2023-0179.

Reported-by: Davide Ornaghi <d.ornaghi97@gmail.com>
Fixes: f6ae9f120d ("netfilter: nft_payload: add C-VLAN support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:48:46 +01:00
Jozsef Kadlecsik
a1e1521b46 netfilter: ipset: Rework long task execution when adding/deleting entries
[ Upstream commit 5e29dc36bd ]

When adding/deleting large number of elements in one step in ipset, it can
take a reasonable amount of time and can result in soft lockup errors. The
patch 5f7b51bf09 ("netfilter: ipset: Limit the maximal range of
consecutive elements to add/delete") tried to fix it by limiting the max
elements to process at all. However it was not enough, it is still possible
that we get hung tasks. Lowering the limit is not reasonable, so the
approach in this patch is as follows: rely on the method used at resizing
sets and save the state when we reach a smaller internal batch limit,
unlock/lock and proceed from the saved state. Thus we can avoid long
continuous tasks and at the same time removed the limit to add/delete large
number of elements in one step.

The nfnl mutex is held during the whole operation which prevents one to
issue other ipset commands in parallel.

Fixes: 5f7b51bf09 ("netfilter: ipset: Limit the maximal range of consecutive elements to add/delete")
Reported-by: syzbot+9204e7399656300bf271@syzkaller.appspotmail.com
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:15 +01:00
Jozsef Kadlecsik
6f19a38483 netfilter: ipset: fix hash:net,port,net hang with /0 subnet
[ Upstream commit a31d47be64 ]

The hash:net,port,net set type supports /0 subnets. However, the patch
commit 5f7b51bf09 titled "netfilter: ipset: Limit the maximal range
of consecutive elements to add/delete" did not take into account it and
resulted in an endless loop. The bug is actually older but the patch
5f7b51bf09 brings it out earlier.

Handle /0 subnets properly in hash:net,port,net set types.

Fixes: 5f7b51bf09 ("netfilter: ipset: Limit the maximal range of consecutive elements to add/delete")
Reported-by: Марк Коренберг <socketpair@gmail.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:15 +01:00
Pablo Neira Ayuso
ac95cdafac netfilter: nf_tables: honor set timeout and garbage collection updates
[ Upstream commit 123b99619c ]

Set timeout and garbage collection interval updates are ignored on
updates. Add transaction to update global set element timeout and
garbage collection interval.

Fixes: 96518518cc ("netfilter: add nftables")
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:09 +01:00
Pablo Neira Ayuso
9d30cb4421 netfilter: nf_tables: perform type checking for existing sets
[ Upstream commit f6594c372a ]

If a ruleset declares a set name that matches an existing set in the
kernel, then validate that this declaration really refers to the same
set, otherwise bail out with EEXIST.

Currently, the kernel reports success when adding a set that already
exists in the kernel. This usually results in EINVAL errors at a later
stage, when the user adds elements to the set, if the set declaration
mismatches the existing set representation in the kernel.

Add a new function to check that the set declaration really refers to
the same existing set in the kernel.

Fixes: 96518518cc ("netfilter: add nftables")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:08 +01:00
Pablo Neira Ayuso
c3bfb7784a netfilter: nf_tables: add function to create set stateful expressions
[ Upstream commit a8fe4154fa ]

Add a helper function to allocate and initialize the stateful expressions
that are defined in a set.

This patch allows to reuse this code from the set update path, to check
that type of the update matches the existing set in the kernel.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: f6594c372a ("netfilter: nf_tables: perform type checking for existing sets")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:08 +01:00
Pablo Neira Ayuso
996cd779c2 netfilter: nf_tables: consolidate set description
[ Upstream commit bed4a63ea4 ]

Add the following fields to the set description:

- key type
- data type
- object type
- policy
- gc_int: garbage collection interval)
- timeout: element timeout

This prepares for stricter set type checks on updates in a follow up
patch.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: f6594c372a ("netfilter: nf_tables: perform type checking for existing sets")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-12 11:59:08 +01:00
Qingfang DENG
74248b5560 netfilter: flowtable: really fix NAT IPv6 offload
[ Upstream commit 5fb45f95ee ]

The for-loop was broken from the start. It translates to:

	for (i = 0; i < 4; i += 4)

which means the loop statement is run only once, so only the highest
32-bit of the IPv6 address gets mangled.

Fix the loop increment.

Fixes: 0e07e25b48 ("netfilter: flowtable: fix NAT IPv6 offload mangling")
Fixes: 5c27d8d76c ("netfilter: nf_flow_table_offload: add IPv6 support")
Signed-off-by: Qingfang DENG <dqfext@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:36 +01:00
Florian Westphal
d78649c21b netfilter: conntrack: set icmpv6 redirects as RELATED
[ Upstream commit 7d7cfb48d8 ]

icmp conntrack will set icmp redirects as RELATED, but icmpv6 will not
do this.

For icmpv6, only icmp errors (code <= 128) are examined for RELATED state.
ICMPV6 Redirects are part of neighbour discovery mechanism, those are
handled by marking a selected subset (e.g.  neighbour solicitations) as
UNTRACKED, but not REDIRECT -- they will thus be flagged as INVALID.

Add minimal support for REDIRECTs.  No parsing of neighbour options is
added for simplicity, so this will only check that we have the embeeded
original header (ND_OPT_REDIRECT_HDR), and then attempt to do a flow
lookup for this tuple.

Also extend the existing test case to cover redirects.

Fixes: 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.")
Reported-by: Eric Garver <eric@garver.life>
Link: https://github.com/firewalld/firewalld/issues/1046
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Garver <eric@garver.life>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:14 +01:00
Pablo Neira Ayuso
f8b2965601 netfilter: ctnetlink: fix compilation warning after data race fixes in ct mark
[ Upstream commit 1feeae0715 ]

All warnings (new ones prefixed by >>):

   net/netfilter/nf_conntrack_netlink.c: In function '__ctnetlink_glue_build':
>> net/netfilter/nf_conntrack_netlink.c:2674:13: warning: unused variable 'mark' [-Wunused-variable]
    2674 |         u32 mark;
         |             ^~~~

Fixes: 52d1aa8b82 ("netfilter: conntrack: Fix data-races around ct mark")
Reported-by: kernel test robot <lkp@intel.com>
Tested-by: Ivan Babrou <ivan@ivan.computer>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14 11:37:23 +01:00
Stefano Brivio
7b09ba9036 netfilter: nft_set_pipapo: Actually validate intervals in fields after the first one
[ Upstream commit 97d4d394b5 ]

Embarrassingly, nft_pipapo_insert() checked for interval validity in
the first field only.

The start_p and end_p pointers were reset to key data from the first
field at every iteration of the loop which was supposed to go over
the set fields.

Fixes: 3c4287f620 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14 11:37:22 +01:00
Felix Fietkau
8db9e60cdf netfilter: flowtable_offload: add missing locking
[ Upstream commit bcd9e3c165 ]

nf_flow_table_block_setup and the driver TC_SETUP_FT call can modify the flow
block cb list while they are being traversed elsewhere, causing a crash.
Add a write lock around the calls to protect readers

Fixes: c29f74e0df ("netfilter: nf_flow_table: hardware offload support")
Reported-by: Chad Monroe <chad.monroe@smartrg.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:06 +01:00
Jozsef Kadlecsik
c1da3bfca1 netfilter: ipset: restore allowing 64 clashing elements in hash:net,iface
[ Upstream commit 6a66ce44a5 ]

The commit 510841da1f ("netfilter: ipset: enforce documented limit to
prevent allocating huge memory") was too strict and prevented to add up to
64 clashing elements to a hash:net,iface type of set. This patch fixes the
issue and now the type behaves as documented.

Fixes: 510841da1f ("netfilter: ipset: enforce documented limit to prevent allocating huge memory")
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:06 +01:00
Vishwanath Pai
8180099b2a netfilter: ipset: regression in ip_set_hash_ip.c
[ Upstream commit c7aa1a76d4 ]

This patch introduced a regression: commit 48596a8ddc ("netfilter:
ipset: Fix adding an IPv4 range containing more than 2^31 addresses")

The variable e.ip is passed to adtfn() function which finally adds the
ip address to the set. The patch above refactored the for loop and moved
e.ip = htonl(ip) to the end of the for loop.

What this means is that if the value of "ip" changes between the first
assignement of e.ip and the forloop, then e.ip is pointing to a
different ip address than "ip".

Test case:
$ ipset create jdtest_tmp hash:ip family inet hashsize 2048 maxelem 100000
$ ipset add jdtest_tmp 10.0.1.1/31
ipset v6.21.1: Element cannot be added to the set: it's already added

The value of ip gets updated inside the  "else if (tb[IPSET_ATTR_CIDR])"
block but e.ip is still pointing to the old value.

Fixes: 48596a8ddc ("netfilter: ipset: Fix adding an IPv4 range containing more than 2^31 addresses")
Reviewed-by: Joshua Hunt <johunt@akamai.com>
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:05 +01:00
Pablo Neira Ayuso
0600615d01 netfilter: nf_tables: do not set up extensions for end interval
[ Upstream commit 33c7aba0b4 ]

Elements with an end interval flag set on do not store extensions. The
global set definition is currently setting on the timeout and stateful
expression for end interval elements.

This leads to skipping end interval elements from the set->ops->walk()
path as the expired check bogusly reports true.

Moreover, do not set up stateful expressions for elements with end
interval flag set on since this is never used.

Fixes: 65038428b2 ("netfilter: nf_tables: allow to specify stateful expression in set definition")
Fixes: 8d8540c4f5 ("netfilter: nft_set_rbtree: add timeout support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:04 +01:00
Daniel Xu
60387731e6 netfilter: conntrack: Fix data-races around ct mark
[ Upstream commit 52d1aa8b82 ]

nf_conn:mark can be read from and written to in parallel. Use
READ_ONCE()/WRITE_ONCE() for reads and writes to prevent unwanted
compiler optimizations.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:41:04 +01:00
Shigeru Yoshida
77ff31cba9 netfilter: Cleanup nft_net->module_list from nf_tables_exit_net()
[ Upstream commit 03c1f1ef15 ]

syzbot reported a warning like below [1]:

WARNING: CPU: 3 PID: 9 at net/netfilter/nf_tables_api.c:10096 nf_tables_exit_net+0x71c/0x840
Modules linked in:
CPU: 2 PID: 9 Comm: kworker/u8:0 Tainted: G        W          6.1.0-rc3-00072-g8e5423e991e8 #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:nf_tables_exit_net+0x71c/0x840
...
Call Trace:
 <TASK>
 ? __nft_release_table+0xfc0/0xfc0
 ops_exit_list+0xb5/0x180
 cleanup_net+0x506/0xb10
 ? unregister_pernet_device+0x80/0x80
 process_one_work+0xa38/0x1730
 ? pwq_dec_nr_in_flight+0x2b0/0x2b0
 ? rwlock_bug.part.0+0x90/0x90
 ? _raw_spin_lock_irq+0x46/0x50
 worker_thread+0x67e/0x10e0
 ? process_one_work+0x1730/0x1730
 kthread+0x2e5/0x3a0
 ? kthread_complete_and_exit+0x40/0x40
 ret_from_fork+0x1f/0x30
 </TASK>

In nf_tables_exit_net(), there is a case where nft_net->commit_list is
empty but nft_net->module_list is not empty.  Such a case occurs with
the following scenario:

1. nfnetlink_rcv_batch() is called
2. nf_tables_newset() returns -EAGAIN and NFNL_BATCH_FAILURE bit is
   set to status
3. nf_tables_abort() is called with NFNL_ABORT_AUTOLOAD
   (nft_net->commit_list is released, but nft_net->module_list is not
   because of NFNL_ABORT_AUTOLOAD flag)
4. Jump to replay label
5. netlink_skb_clone() fails and returns from the function (this is
   caused by fault injection in the reproducer of syzbot)

This patch fixes this issue by calling __nf_tables_abort() when
nft_net->module_list is not empty in nf_tables_exit_net().

Fixes: eb014de4fd ("netfilter: nf_tables: autoload modules from the abort path")
Link: https://syzkaller.appspot.com/bug?id=802aba2422de4218ad0c01b46c9525cc9d4e4aa3 [1]
Reported-by: syzbot+178efee9e2d7f87f5103@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:20 +01:00
Ziyang Xuan
e62cb1c093 netfilter: nfnetlink: fix potential dead lock in nfnetlink_rcv_msg()
[ Upstream commit 03832a32bf ]

When type is NFNL_CB_MUTEX and -EAGAIN error occur in nfnetlink_rcv_msg(),
it does not execute nfnl_unlock(). That would trigger potential dead lock.

Fixes: 50f2db9e36 ("netfilter: nfnetlink: consolidate callback types")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-16 09:58:20 +01:00
Jozsef Kadlecsik
42d20d5e24 netfilter: ipset: enforce documented limit to prevent allocating huge memory
[ Upstream commit 510841da1f ]

Daniel Xu reported that the hash:net,iface type of the ipset subsystem does
not limit adding the same network with different interfaces to a set, which
can lead to huge memory usage or allocation failure.

The quick reproducer is

$ ipset create ACL.IN.ALL_PERMIT hash:net,iface hashsize 1048576 timeout 0
$ for i in $(seq 0 100); do /sbin/ipset add ACL.IN.ALL_PERMIT 0.0.0.0/0,kaf_$i timeout 0 -exist; done

The backtrace when vmalloc fails:

        [Tue Oct 25 00:13:08 2022] ipset: vmalloc error: size 1073741848, exceeds total pages
        <...>
        [Tue Oct 25 00:13:08 2022] Call Trace:
        [Tue Oct 25 00:13:08 2022]  <TASK>
        [Tue Oct 25 00:13:08 2022]  dump_stack_lvl+0x48/0x60
        [Tue Oct 25 00:13:08 2022]  warn_alloc+0x155/0x180
        [Tue Oct 25 00:13:08 2022]  __vmalloc_node_range+0x72a/0x760
        [Tue Oct 25 00:13:08 2022]  ? hash_netiface4_add+0x7c0/0xb20
        [Tue Oct 25 00:13:08 2022]  ? __kmalloc_large_node+0x4a/0x90
        [Tue Oct 25 00:13:08 2022]  kvmalloc_node+0xa6/0xd0
        [Tue Oct 25 00:13:08 2022]  ? hash_netiface4_resize+0x99/0x710
        <...>

The fix is to enforce the limit documented in the ipset(8) manpage:

>  The internal restriction of the hash:net,iface set type is that the same
>  network prefix cannot be stored with more than 64 different interfaces
>  in a single set.

Fixes: ccf0a4b7fc ("netfilter: ipset: Add bucketsize parameter to all hash types")
Reported-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:30 +01:00
Zhengchao Shao
06d7596d18 ipvs: fix WARNING in ip_vs_app_net_cleanup()
[ Upstream commit 5663ed63ad ]

During the initialization of ip_vs_app_net_init(), if file ip_vs_app
fails to be created, the initialization is successful by default.
Therefore, the ip_vs_app file doesn't be found during the remove in
ip_vs_app_net_cleanup(). It will cause WRNING.

The following is the stack information:
name 'ip_vs_app'
WARNING: CPU: 1 PID: 9 at fs/proc/generic.c:712 remove_proc_entry+0x389/0x460
Modules linked in:
Workqueue: netns cleanup_net
RIP: 0010:remove_proc_entry+0x389/0x460
Call Trace:
<TASK>
ops_exit_list+0x125/0x170
cleanup_net+0x4ea/0xb00
process_one_work+0x9bf/0x1710
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
</TASK>

Fixes: 457c4cbc5a ("[NET]: Make /proc/net per network namespace")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:29 +01:00
Zhengchao Shao
5ee2d6b726 ipvs: fix WARNING in __ip_vs_cleanup_batch()
[ Upstream commit 3d00c6a0da ]

During the initialization of ip_vs_conn_net_init(), if file ip_vs_conn
or ip_vs_conn_sync fails to be created, the initialization is successful
by default. Therefore, the ip_vs_conn or ip_vs_conn_sync file doesn't
be found during the remove.

The following is the stack information:
name 'ip_vs_conn_sync'
WARNING: CPU: 3 PID: 9 at fs/proc/generic.c:712
remove_proc_entry+0x389/0x460
Modules linked in:
Workqueue: netns cleanup_net
RIP: 0010:remove_proc_entry+0x389/0x460
Call Trace:
<TASK>
__ip_vs_cleanup_batch+0x7d/0x120
ops_exit_list+0x125/0x170
cleanup_net+0x4ea/0xb00
process_one_work+0x9bf/0x1710
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
</TASK>

Fixes: 61b1ab4583 ("IPVS: netns, add basic init per netns.")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:29 +01:00
Jason A. Donenfeld
33e7783bc0 ipvs: use explicitly signed chars
[ Upstream commit 5c26159c97 ]

The `char` type with no explicit sign is sometimes signed and sometimes
unsigned. This code will break on platforms such as arm, where char is
unsigned. So mark it here as explicitly signed, so that the
todrop_counter decrement and subsequent comparison is correct.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:29 +01:00
Pablo Neira Ayuso
6044791b7b netfilter: nf_tables: release flow rule object from commit path
[ Upstream commit 26b5934ff4 ]

No need to postpone this to the commit release path, since no packets
are walking over this object, this is accessed from control plane only.
This helped uncovered UAF triggered by races with the netlink notifier.

Fixes: 9dd732e0bd ("netfilter: nf_tables: memleak flow rule from commit path")
Reported-by: syzbot+8f747f62763bc6c32916@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:28 +01:00
Pablo Neira Ayuso
1ffe710041 netfilter: nf_tables: netlink notifier might race to release objects
[ Upstream commit d4bc8271db ]

commit release path is invoked via call_rcu and it runs lockless to
release the objects after rcu grace period. The netlink notifier handler
might win race to remove objects that the transaction context is still
referencing from the commit release path.

Call rcu_barrier() to ensure pending rcu callbacks run to completion
if the list of transactions to be destroyed is not empty.

Fixes: 6001a930ce ("netfilter: nftables: introduce table ownership")
Reported-by: syzbot+8f747f62763bc6c32916@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:15:28 +01:00
Pablo Neira Ayuso
d77f6908f9 netfilter: nf_tables: relax NFTA_SET_ELEM_KEY_END set flags requirements
[ Upstream commit 96df8360db ]

Otherwise EINVAL is bogusly reported to userspace when deleting a set
element. NFTA_SET_ELEM_KEY_END does not need to be set in case of:

- insertion: if not present, start key is used as end key.
- deletion: only start key needs to be specified, end key is ignored.

Hence, relax the sanity check.

Fixes: 88cccd908d ("netfilter: nf_tables: NFTA_SET_ELEM_KEY_END requires concat and interval flags")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-29 10:12:56 +02:00
Antoine Tenart
5a6827cdc2 netfilter: conntrack: revisit the gc initial rescheduling bias
[ Upstream commit 2aa1927570 ]

The previous commit changed the way the rescheduling delay is computed
which has a side effect: the bias is now represented as much as the
other entries in the rescheduling delay which makes the logic to kick in
only with very large sets, as the initial interval is very large
(INT_MAX).

Revisit the GC initial bias to allow more frequent GC for smaller sets
while still avoiding wakeups when a machine is mostly idle. We're moving
from a large initial value to pretending we have 100 entries expiring at
the upper bound. This way only a few entries having a small timeout
won't impact much the rescheduling delay and non-idle machines will have
enough entries to lower the delay when needed. This also improves
readability as the initial bias is now linked to what is computed
instead of being an arbitrary large value.

Fixes: 2cfadb761d ("netfilter: conntrack: revisit gc autotuning")
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:34:45 +02:00
Antoine Tenart
9c39ca418b netfilter: conntrack: fix the gc rescheduling delay
[ Upstream commit 95eabdd207 ]

Commit 2cfadb761d ("netfilter: conntrack: revisit gc autotuning")
changed the eviction rescheduling to the use average expiry of scanned
entries (within 1-60s) by doing:

  for (...) {
      expires = clamp(nf_ct_expires(tmp), ...);
      next_run += expires;
      next_run /= 2;
  }

The issue is the above will make the average ('next_run' here) more
dependent on the last expiration values than the firsts (for sets > 2).
Depending on the expiration values used to compute the average, the
result can be quite different than what's expected. To fix this we can
do the following:

  for (...) {
      expires = clamp(nf_ct_expires(tmp), ...);
      next_run += (expires - next_run) / ++count;
  }

Fixes: 2cfadb761d ("netfilter: conntrack: revisit gc autotuning")
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 12:34:44 +02:00
Tetsuo Handa
08d7524f36 netfilter: nf_tables: fix percpu memory leak at nf_tables_addchain()
[ Upstream commit 9a4d6dd554 ]

It seems to me that percpu memory for chain stats started leaking since
commit 3bc158f8d0 ("netfilter: nf_tables: map basechain priority to
hardware priority") when nft_chain_offload_priority() returned an error.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 3bc158f8d0 ("netfilter: nf_tables: map basechain priority to hardware priority")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:11:51 +02:00
Tetsuo Handa
91aa52652f netfilter: nf_tables: fix nft_counters_enabled underflow at nf_tables_addchain()
[ Upstream commit 921ebde3c0 ]

syzbot is reporting underflow of nft_counters_enabled counter at
nf_tables_addchain() [1], for commit 43eb8949cf ("netfilter:
nf_tables: do not leave chain stats enabled on error") missed that
nf_tables_chain_destroy() after nft_basechain_init() in the error path of
nf_tables_addchain() decrements the counter because nft_basechain_init()
makes nft_is_base_chain() return true by setting NFT_CHAIN_BASE flag.

Increment the counter immediately after returning from
nft_basechain_init().

Link:  https://syzkaller.appspot.com/bug?extid=b5d82a651b71cd8a75ab [1]
Reported-by: syzbot <syzbot+b5d82a651b71cd8a75ab@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+b5d82a651b71cd8a75ab@syzkaller.appspotmail.com>
Fixes: 43eb8949cf ("netfilter: nf_tables: do not leave chain stats enabled on error")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:11:51 +02:00
Pablo Neira Ayuso
816eab147e netfilter: nfnetlink_osf: fix possible bogus match in nf_osf_find()
[ Upstream commit 559c36c5a8 ]

nf_osf_find() incorrectly returns true on mismatch, this leads to
copying uninitialized memory area in nft_osf which can be used to leak
stale kernel stack data to userspace.

Fixes: 22c7652cda ("netfilter: nft_osf: Add version option support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:11:47 +02:00
David Leadbeater
dc33ffbc36 netfilter: nf_conntrack_irc: Tighten matching on DCC message
[ Upstream commit e8d5dfd1d8 ]

CTCP messages should only be at the start of an IRC message, not
anywhere within it.

While the helper only decodes packes in the ORIGINAL direction, its
possible to make a client send a CTCP message back by empedding one into
a PING request.  As-is, thats enough to make the helper believe that it
saw a CTCP message.

Fixes: 869f37d8e4 ("[NETFILTER]: nf_conntrack/nf_nat: add IRC helper port")
Signed-off-by: David Leadbeater <dgl@dgl.cx>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:11:46 +02:00
Igor Ryzhov
0606c5d5fe netfilter: nf_conntrack_sip: fix ct_sip_walk_headers
[ Upstream commit 39aebedeaa ]

ct_sip_next_header and ct_sip_get_header return an absolute
value of matchoff, not a shift from current dataoff.
So dataoff should be assigned matchoff, not incremented by it.

This issue can be seen in the scenario when there are multiple
Contact headers and the first one is using a hostname and other headers
use IP addresses. In this case, ct_sip_walk_headers will work as follows:

The first ct_sip_get_header call to will find the first Contact header
but will return -1 as the header uses a hostname. But matchoff will
be changed to the offset of this header. After that, dataoff should be
set to matchoff, so that the next ct_sip_get_header call find the next
Contact header. But instead of assigning dataoff to matchoff, it is
incremented by it, which is not correct, as matchoff is an absolute
value of the offset. So on the next call to the ct_sip_get_header,
dataoff will be incorrect, and the next Contact header may not be
found at all.

Fixes: 05e3ced297 ("[NETFILTER]: nf_conntrack_sip: introduce SIP-URI parsing helper")
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:11:46 +02:00
David Leadbeater
451c9ce1e2 netfilter: nf_conntrack_irc: Fix forged IP logic
[ Upstream commit 0efe125cfb ]

Ensure the match happens in the right direction, previously the
destination used was the server, not the NAT host, as the comment
shows the code intended.

Additionally nf_nat_irc uses port 0 as a signal and there's no valid way
it can appear in a DCC message, so consider port 0 also forged.

Fixes: 869f37d8e4 ("[NETFILTER]: nf_conntrack/nf_nat: add IRC helper port")
Signed-off-by: David Leadbeater <dgl@dgl.cx>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:04 +02:00
Pablo Neira Ayuso
1ce55ec5cb netfilter: nf_tables: clean up hook list when offload flags check fails
[ Upstream commit 77972a36ec ]

splice back the hook list so nft_chain_release_hook() has a chance to
release the hooks.

BUG: memory leak
unreferenced object 0xffff88810180b100 (size 96):
  comm "syz-executor133", pid 3619, jiffies 4294945714 (age 12.690s)
  hex dump (first 32 bytes):
    28 64 23 02 81 88 ff ff 28 64 23 02 81 88 ff ff  (d#.....(d#.....
    90 a8 aa 83 ff ff ff ff 00 00 b5 0f 81 88 ff ff  ................
  backtrace:
    [<ffffffff83a8c59b>] kmalloc include/linux/slab.h:600 [inline]
    [<ffffffff83a8c59b>] nft_netdev_hook_alloc+0x3b/0xc0 net/netfilter/nf_tables_api.c:1901
    [<ffffffff83a9239a>] nft_chain_parse_netdev net/netfilter/nf_tables_api.c:1998 [inline]
    [<ffffffff83a9239a>] nft_chain_parse_hook+0x33a/0x530 net/netfilter/nf_tables_api.c:2073
    [<ffffffff83a9b14b>] nf_tables_addchain.constprop.0+0x10b/0x950 net/netfilter/nf_tables_api.c:2218
    [<ffffffff83a9c41b>] nf_tables_newchain+0xa8b/0xc60 net/netfilter/nf_tables_api.c:2593
    [<ffffffff83a3d6a6>] nfnetlink_rcv_batch+0xa46/0xd20 net/netfilter/nfnetlink.c:517
    [<ffffffff83a3db79>] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:638 [inline]
    [<ffffffff83a3db79>] nfnetlink_rcv+0x1f9/0x220 net/netfilter/nfnetlink.c:656
    [<ffffffff83a13b17>] netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
    [<ffffffff83a13b17>] netlink_unicast+0x397/0x4c0 net/netlink/af_netlink.c:1345
    [<ffffffff83a13fd6>] netlink_sendmsg+0x396/0x710 net/netlink/af_netlink.c:1921
    [<ffffffff83865ab6>] sock_sendmsg_nosec net/socket.c:714 [inline]
    [<ffffffff83865ab6>] sock_sendmsg+0x56/0x80 net/socket.c:734
    [<ffffffff8386601c>] ____sys_sendmsg+0x36c/0x390 net/socket.c:2482
    [<ffffffff8386a918>] ___sys_sendmsg+0xa8/0x110 net/socket.c:2536
    [<ffffffff8386aaa8>] __sys_sendmsg+0x88/0x100 net/socket.c:2565
    [<ffffffff845e5955>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    [<ffffffff845e5955>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
    [<ffffffff84800087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: d54725cd11 ("netfilter: nf_tables: support for multiple devices per netdev hook")
Reported-by: syzbot+5fcdbfab6d6744c57418@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:04 +02:00
Florian Westphal
e928cf2589 netfilter: conntrack: work around exceeded receive window
[ Upstream commit cf97769c76 ]

When a TCP sends more bytes than allowed by the receive window, all future
packets can be marked as invalid.
This can clog up the conntrack table because of 5-day default timeout.

Sequence of packets:
 01 initiator > responder: [S], seq 171, win 5840, options [mss 1330,sackOK,TS val 63 ecr 0,nop,wscale 1]
 02 responder > initiator: [S.], seq 33211, ack 172, win 65535, options [mss 1460,sackOK,TS val 010 ecr 63,nop,wscale 8]
 03 initiator > responder: [.], ack 33212, win 2920, options [nop,nop,TS val 068 ecr 010], length 0
 04 initiator > responder: [P.], seq 172:240, ack 33212, win 2920, options [nop,nop,TS val 279 ecr 010], length 68

Window is 5840 starting from 33212 -> 39052.

 05 responder > initiator: [.], ack 240, win 256, options [nop,nop,TS val 872 ecr 279], length 0
 06 responder > initiator: [.], seq 33212:34530, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 1318

This is fine, conntrack will flag the connection as having outstanding
data (UNACKED), which lowers the conntrack timeout to 300s.

 07 responder > initiator: [.], seq 34530:35848, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 1318
 08 responder > initiator: [.], seq 35848:37166, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 1318
 09 responder > initiator: [.], seq 37166:38484, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 1318
 10 responder > initiator: [.], seq 38484:39802, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 1318

Packet 10 is already sending more than permitted, but conntrack doesn't
validate this (only seq is tested vs. maxend, not 'seq+len').

38484 is acceptable, but only up to 39052, so this packet should
not have been sent (or only 568 bytes, not 1318).

At this point, connection is still in '300s' mode.

Next packet however will get flagged:
 11 responder > initiator: [P.], seq 39802:40128, ack 240, win 256, options [nop,nop,TS val 892 ecr 279], length 326

nf_ct_proto_6: SEQ is over the upper bound (over the window of the receiver) .. LEN=378 .. SEQ=39802 ACK=240 ACK PSH ..

Now, a couple of replies/acks comes in:

 12 initiator > responder: [.], ack 34530, win 4368,
[.. irrelevant acks removed ]
 16 initiator > responder: [.], ack 39802, win 8712, options [nop,nop,TS val 296201291 ecr 2982371892], length 0

This ack is significant -- this acks the last packet send by the
responder that conntrack considered valid.

This means that ack == td_end.  This will withdraw the
'unacked data' flag, the connection moves back to the 5-day timeout
of established conntracks.

 17 initiator > responder: ack 40128, win 10030, ...

This packet is also flagged as invalid.

Because conntrack only updates state based on packets that are
considered valid, packet 11 'did not exist' and that gets us:

nf_ct_proto_6: ACK is over upper bound 39803 (ACKed data not seen yet) .. SEQ=240 ACK=40128 WINDOW=10030 RES=0x00 ACK URG

Because this received and processed by the endpoints, the conntrack entry
remains in a bad state, no packets will ever be considered valid again:

 30 responder > initiator: [F.], seq 40432, ack 2045, win 391, ..
 31 initiator > responder: [.], ack 40433, win 11348, ..
 32 initiator > responder: [F.], seq 2045, ack 40433, win 11348 ..

... all trigger 'ACK is over bound' test and we end up with
non-early-evictable 5-day default timeout.

NB: This patch triggers a bunch of checkpatch warnings because of silly
indent.  I will resend the cleanup series linked below to reduce the
indent level once this change has propagated to net-next.

I could route the cleanup via nf but that causes extra backport work for
stable maintainers.

Link: https://lore.kernel.org/netfilter-devel/20220720175228.17880-1-fw@strlen.de/T/#mb1d7147d36294573cc4f81d00f9f8dadfdd06cd8
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 11:30:01 +02:00