linux-stable.git/net/netfilter, branch v4.19.151

netfilter: ctnetlink: add a range check for l3/l4 protonum

2020-10-07T06:00:09+00:00

commit 1cc5ef91d2ff94d2bf2de3b3585423e8a1051cb6 upstream.

The indexes to the nf_nat_l[34]protos arrays come from userspace. So
check the tuple's family, e.g. l3num, when creating the conntrack in
order to prevent an OOB memory access during setup.  Here is an example
kernel panic on 4.14.180 when userspace passes in an index greater than
NFPROTO_NUMPROTO.

Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:...
Process poc (pid: 5614, stack limit = 0x00000000a3933121)
CPU: 4 PID: 5614 Comm: poc Tainted: G S      W  O    4.14.180-g051355490483
Hardware name: Qualcomm Technologies, Inc. SM8150 V2 PM8150 Google Inc. MSM
task: 000000002a3dfffe task.stack: 00000000a3933121
pc : __cfi_check_fail+0x1c/0x24
lr : __cfi_check_fail+0x1c/0x24
...
Call trace:
__cfi_check_fail+0x1c/0x24
name_to_dev_t+0x0/0x468
nfnetlink_parse_nat_setup+0x234/0x258
ctnetlink_parse_nat_setup+0x4c/0x228
ctnetlink_new_conntrack+0x590/0xc40
nfnetlink_rcv_msg+0x31c/0x4d4
netlink_rcv_skb+0x100/0x184
nfnetlink_rcv+0xf4/0x180
netlink_unicast+0x360/0x770
netlink_sendmsg+0x5a0/0x6a4
___sys_sendmsg+0x314/0x46c
SyS_sendmsg+0xb4/0x108
el0_svc_naked+0x34/0x38

This crash is not happening since 5.4+, however, ctnetlink still
allows for creating entries with unsupported layer 3 protocol number.

Fixes: c1d10adb4a521 ("[NETFILTER]: Add ctnetlink port for nf_conntrack")
Signed-off-by: Will McVicker 
[pablo@netfilter.org: rebased original patch on top of nf.git]
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: conntrack: allow sctp hearbeat after connection re-use

2020-09-17T11:45:24+00:00

[ Upstream commit cc5453a5b7e90c39f713091a7ebc53c1f87d1700 ]

If an sctp connection gets re-used, heartbeats are flagged as invalid
because their vtag doesn't match.

Handle this in a similar way as TCP conntrack when it suspects that the
endpoints and conntrack are out-of-sync.

When a HEARTBEAT request fails its vtag validation, flag this in the
conntrack state and accept the packet.

When a HEARTBEAT_ACK is received with an invalid vtag in the reverse
direction after we allowed such a HEARTBEAT through, assume we are
out-of-sync and re-set the vtag info.

v2: remove left-over snippet from an older incarnation that moved
    new_state/old_state assignments, thats not needed so keep that
    as-is.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nfnetlink: nfnetlink_unicast() reports EAGAIN instead of ENOBUFS

2020-09-09T17:04:26+00:00

[ Upstream commit ee921183557af39c1a0475f982d43b0fcac25e2e ]

Frontend callback reports EAGAIN to nfnetlink to retry a command, this
is used to signal that module autoloading is required. Unfortunately,
nlmsg_unicast() reports EAGAIN in case the receiver socket buffer gets
full, so it enters a busy-loop.

This patch updates nfnetlink_unicast() to turn EAGAIN into ENOBUFS and
to use nlmsg_unicast(). Remove the flags field in nfnetlink_unicast()
since this is always MSG_DONTWAIT in the existing code which is exactly
what nlmsg_unicast() passes to netlink_unicast() as parameter.

Fixes: 96518518cc41 ("netfilter: add nftables")
Reported-by: Phil Sutter 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: fix destination register zeroing

2020-09-09T17:04:25+00:00

[ Upstream commit 1e105e6afa6c3d32bfb52c00ffa393894a525c27 ]

Following bug was reported via irc:
nft list ruleset
   set knock_candidates_ipv4 {
      type ipv4_addr . inet_service
      size 65535
      elements = { 127.0.0.1 . 123,
                   127.0.0.1 . 123 }
      }
 ..
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . 123 }
   udp dport 123 add @knock_candidates_ipv4 { ip saddr . udp dport }

It should not have been possible to add a duplicate set entry.

After some debugging it turned out that the problem is the immediate
value (123) in the second-to-last rule.

Concatenations use 32bit registers, i.e. the elements are 8 bytes each,
not 6 and it turns out the kernel inserted

inet firewall @knock_candidates_ipv4
        element 0100007f ffff7b00  : 0 [end]
        element 0100007f 00007b00  : 0 [end]

Note the non-zero upper bits of the first element.  It turns out that
nft_immediate doesn't zero the destination register, but this is needed
when the length isn't a multiple of 4.

Furthermore, the zeroing in nft_payload is broken.  We can't use
[len / 4] = 0 -- if len is a multiple of 4, index is off by one.

Skip zeroing in this case and use a conditional instead of (len -1) / 4.

Fixes: 49499c3e6e18 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: add NFTA_SET_USERDATA if not null

2020-09-09T17:04:24+00:00

[ Upstream commit 6f03bf43ee05b31d3822def2a80f11b3591c55b3 ]

Kernel sends an empty NFTA_SET_USERDATA attribute with no value if
userspace adds a set with no NFTA_SET_USERDATA attribute.

Fixes: e6d8ecac9e68 ("netfilter: nf_tables: Add new attributes into nft_set to store user data.")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

ipvs: allow connection reuse for unconfirmed conntrack

2020-08-19T06:14:56+00:00

[ Upstream commit f0a5e4d7a594e0fe237d3dfafb069bb82f80f42f ]

YangYuxi is reporting that connection reuse
is causing one-second delay when SYN hits
existing connection in TIME_WAIT state.
Such delay was added to give time to expire
both the IPVS connection and the corresponding
conntrack. This was considered a rare case
at that time but it is causing problem for
some environments such as Kubernetes.

As nf_conntrack_tcp_packet() can decide to
release the conntrack in TIME_WAIT state and
to replace it with a fresh NEW conntrack, we
can use this to allow rescheduling just by
tuning our check: if the conntrack is
confirmed we can not schedule it to different
real server and the one-second delay still
applies but if new conntrack was created,
we are free to select new real server without
any delays.

YangYuxi lists some of the problem reports:

- One second connection delay in masquerading mode:
https://marc.info/?t=151683118100004&r=1&w=2

- IPVS low throughput #70747
https://github.com/kubernetes/kubernetes/issues/70747

- Apache Bench can fill up ipvs service proxy in seconds #544
https://github.com/cloudnativelabs/kube-router/issues/544

- Additional 1s latency in `host -> service IP -> pod`
https://github.com/kubernetes/kubernetes/issues/90854

Fixes: f719e3754ee2 ("ipvs: drop first packet to redirect conntrack")
Co-developed-by: YangYuxi 
Signed-off-by: YangYuxi 
Signed-off-by: Julian Anastasov 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

ipvs: fix the connection sync failed in some cases

2020-07-29T08:16:50+00:00

[ Upstream commit 8210e344ccb798c672ab237b1a4f241bda08909b ]

The sync_thread_backup only checks sk_receive_queue is empty or not,
there is a situation which cannot sync the connection entries when
sk_receive_queue is empty and sk_rmem_alloc is larger than sk_rcvbuf,
the sync packets are dropped in __udp_enqueue_schedule_skb, this is
because the packets in reader_queue is not read, so the rmem is
not reclaimed.

Here I add the check of whether the reader_queue of the udp sock is
empty or not to solve this problem.

Fixes: 2276f58ac589 ("udp: use a separate rx queue for packet reception")
Reported-by: zhouxudong 
Signed-off-by: guodeqing 
Acked-by: Julian Anastasov 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: ipset: fix unaligned atomic access

2020-07-01T03:17:12+00:00

[ Upstream commit 715028460082d07a7ec6fcd87b14b46784346a72 ]

When using ip_set with counters and comment, traffic causes the kernel
to panic on 32-bit ARM:

Alignment trap: not handling instruction e1b82f9f at []
Unhandled fault: alignment exception (0x221) at 0xea08133c
PC is at ip_set_match_extensions+0xe0/0x224 [ip_set]

The problem occurs when we try to update the 64-bit counters - the
faulting address above is not 64-bit aligned.  The problem occurs
due to the way elements are allocated, for example:

	set->dsize = ip_set_elem_len(set, tb, 0, 0);
	map = ip_set_alloc(sizeof(*map) + elements * set->dsize);

If the element has a requirement for a member to be 64-bit aligned,
and set->dsize is not a multiple of 8, but is a multiple of four,
then every odd numbered elements will be misaligned - and hitting
an atomic64_add() on that element will cause the kernel to panic.

ip_set_elem_len() must return a size that is rounded to the maximum
alignment of any extension field stored in the element.  This change
ensures that is the case.

Fixes: 95ad1f4a9358 ("netfilter: ipset: Fix extension alignment")
Signed-off-by: Russell King 
Acked-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nft_nat: return EOPNOTSUPP if type or flags are not supported

2020-06-22T07:05:14+00:00

[ Upstream commit 0d7c83463fdf7841350f37960a7abadd3e650b41 ]

Instead of EINVAL which should be used for malformed netlink messages.

Fixes: eb31628e37a0 ("netfilter: nf_tables: Add support for IPv6 NAT")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_conntrack_pptp: fix compilation warning with W=1 build

2020-06-03T06:19:49+00:00

commit 4946ea5c1237036155c3b3a24f049fd5f849f8f6 upstream.

>> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
extern const char *const pptp_msg_name(u_int16_t msg);
^~~~~~

Reported-by: kbuild test robot 
Fixes: 4c559f15efcc ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman