linux-stable.git/net/ipv6, branch v6.5.7

ipv6: tcp: add a missing nf_reset_ct() in 3WHS handling

2023-10-10T20:03:02+00:00

[ Upstream commit 9593c7cb6cf670ef724d17f7f9affd7a8d2ad0c5 ]

Commit b0e214d21203 ("netfilter: keep conntrack reference until
IPsecv6 policy checks are done") is a direct copy of the old
commit b59c270104f0 ("[NETFILTER]: Keep conntrack reference until
IPsec policy checks are done") but for IPv6.  However, it also
copies a bug that this old commit had.  That is: when the third
packet of 3WHS connection establishment contains payload, it is
added into socket receive queue without the XFRM check and the
drop of connection tracking context.

That leads to nf_conntrack module being impossible to unload as
it waits for all the conntrack references to be dropped while
the packet release is deferred in per-cpu cache indefinitely, if
not consumed by the application.

The issue for IPv4 was fixed in commit 6f0012e35160 ("tcp: add a
missing nf_reset_ct() in 3WHS handling") by adding a missing XFRM
check and correctly dropping the conntrack context.  However, the
issue was introduced to IPv6 code afterwards.  Fixing it the
same way for IPv6 now.

Fixes: b0e214d21203 ("netfilter: keep conntrack reference until IPsecv6 policy checks are done")
Link: https://lore.kernel.org/netdev/d589a999-d4dd-2768-b2d5-89dec64a4a42@ovn.org/
Signed-off-by: Ilya Maximets 
Acked-by: Florian Westphal 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20230922210530.2045146-1-i.maximets@ovn.org
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

net: release reference to inet6_dev pointer

2023-10-10T20:02:55+00:00

commit 5cb249686e67dbef3ffe53887fa725eefc5a7144 upstream.

addrconf_prefix_rcv returned early without releasing the inet6_dev
pointer when the PIO lifetime is less than accept_ra_min_lft.

Fixes: 5027d54a9c30 ("net: change accept_ra_min_rtr_lft to affect all RA lifetimes")
Cc: Maciej Żenczykowski 
Cc: Lorenzo Colitti 
Cc: David Ahern 
Cc: Simon Horman 
Reviewed-by: Simon Horman 
Reviewed-by: Maciej Żenczykowski 
Signed-off-by: Patrick Rohr 
Reviewed-by: Leon Romanovsky 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: change accept_ra_min_rtr_lft to affect all RA lifetimes

2023-10-10T20:02:55+00:00

commit 5027d54a9c30bc7ec808360378e2b4753f053f25 upstream.

accept_ra_min_rtr_lft only considered the lifetime of the default route
and discarded entire RAs accordingly.

This change renames accept_ra_min_rtr_lft to accept_ra_min_lft, and
applies the value to individual RA sections; in particular, router
lifetime, PIO preferred lifetime, and RIO lifetime. If any of those
lifetimes are lower than the configured value, the specific RA section
is ignored.

In order for the sysctl to be useful to Android, it should really apply
to all lifetimes in the RA, since that is what determines the minimum
frequency at which RAs must be processed by the kernel. Android uses
hardware offloads to drop RAs for a fraction of the minimum of all
lifetimes present in the RA (some networks have very frequent RAs (5s)
with high lifetimes (2h)). Despite this, we have encountered networks
that set the router lifetime to 30s which results in very frequent CPU
wakeups. Instead of disabling IPv6 (and dropping IPv6 ethertype in the
WiFi firmware) entirely on such networks, it seems better to ignore the
misconfigured routers while still processing RAs from other IPv6 routers
on the same network (i.e. to support IoT applications).

The previous implementation dropped the entire RA based on router
lifetime. This turned out to be hard to expand to the other lifetimes
present in the RA in a consistent manner; dropping the entire RA based
on RIO/PIO lifetimes would essentially require parsing the whole thing
twice.

Fixes: 1671bcfd76fd ("net: add sysctl accept_ra_min_rtr_lft")
Cc: Lorenzo Colitti 
Signed-off-by: Patrick Rohr 
Reviewed-by: Maciej Żenczykowski 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20230726230701.919212-1-prohr@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: add sysctl accept_ra_min_rtr_lft

2023-10-10T20:02:55+00:00

commit 1671bcfd76fdc0b9e65153cf759153083755fe4c upstream.

This change adds a new sysctl accept_ra_min_rtr_lft to specify the
minimum acceptable router lifetime in an RA. If the received RA router
lifetime is less than the configured value (and not 0), the RA is
ignored.
This is useful for mobile devices, whose battery life can be impacted
by networks that configure RAs with a short lifetime. On such networks,
the device should never gain IPv6 provisioning and should attempt to
drop RAs via hardware offload, if available.

Signed-off-by: Patrick Rohr 
Cc: Maciej Żenczykowski 
Cc: Lorenzo Colitti 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ipv6/addrconf: avoid integer underflow in ipv6_create_tempaddr

2023-09-19T10:30:18+00:00

[ Upstream commit f31867d0d9d82af757c1e0178b659438f4c1ea3c ]

The existing code incorrectly casted a negative value (the result of a
subtraction) to an unsigned value without checking. For example, if
/proc/sys/net/ipv6/conf/*/temp_prefered_lft was set to 1, the preferred
lifetime would jump to 4 billion seconds. On my machine and network the
shortest lifetime that avoided underflow was 3 seconds.

Fixes: 76506a986dc3 ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: Alex Henrie 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ipv6: ignore dst hint for multipath routes

2023-09-19T10:30:17+00:00

[ Upstream commit 8423be8926aa82cd2e28bba5cc96ccb72c7ce6be ]

Route hints when the nexthop is part of a multipath group causes packets
in the same receive batch to be sent to the same nexthop irrespective of
the multipath hash of the packet. So, do not extract route hint for
packets whose destination is part of a multipath group.

A new SKB flag IP6SKB_MULTIPATH is introduced for this purpose, set the
flag when route is looked up in fib6_select_path() and use it in
ip6_can_use_hint() to check for the existence of the flag.

Fixes: 197dbf24e360 ("ipv6: introduce and uses route look hints for list input.")
Signed-off-by: Sriram Yagnaraman 
Reviewed-by: Ido Schimmel 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: annotate data-races around sk->sk_tsflags

2023-09-19T10:30:17+00:00

[ Upstream commit e3390b30a5dfb112e8e802a59c0f68f947b638b2 ]

sk->sk_tsflags can be read locklessly, add corresponding annotations.

Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags")
Signed-off-by: Eric Dumazet 
Cc: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

lwt: Check LWTUNNEL_XMIT_CONTINUE strictly

2023-09-13T07:53:07+00:00

[ Upstream commit a171fbec88a2c730b108c7147ac5e7b2f5a02b47 ]

LWTUNNEL_XMIT_CONTINUE is implicitly assumed in ip(6)_finish_output2,
such that any positive return value from a xmit hook could cause
unexpected continue behavior, despite that related skb may have been
freed. This could be error-prone for future xmit hook ops. One of the
possible errors is to return statuses of dst_output directly.

To make the code safer, redefine LWTUNNEL_XMIT_CONTINUE value to
distinguish from dst_output statuses and check the continue
condition explicitly.

Fixes: 3a0af8fd61f9 ("bpf: BPF for lightweight tunnel infrastructure")
Suggested-by: Dan Carpenter 
Signed-off-by: Yan Zhai 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/96b939b85eda00e8df4f7c080f770970a4c5f698.1692326837.git.yan@cloudflare.com
Signed-off-by: Sasha Levin

udp: re-score reuseport groups when connected sockets are present

2023-09-13T07:53:03+00:00

[ Upstream commit f0ea27e7bfe1c34e1f451a63eb68faa1d4c3a86d ]

Contrary to TCP, UDP reuseport groups can contain TCP_ESTABLISHED
sockets. To support these properly we remember whether a group has
a connected socket and skip the fast reuseport early-return. In
effect we continue scoring all reuseport sockets and then choose the
one with the highest score.

The current code fails to re-calculate the score for the result of
lookup_reuseport. According to Kuniyuki Iwashima:

    1) SO_INCOMING_CPU is set
       -> selected sk might have +1 score

    2) BPF prog returns ESTABLISHED and/or SO_INCOMING_CPU sk
       -> selected sk will have more than 8

  Using the old score could trigger more lookups depending on the
  order that sockets are created.

    sk -> sk (SO_INCOMING_CPU) -> sk (ESTABLISHED)
    |     |
    `-> select the next SO_INCOMING_CPU sk
          |
          `-> select itself (We should save this lookup)

Fixes: efc6b6f6c311 ("udp: Improve load balancing for SO_REUSEPORT.")
Reviewed-by: Kuniyuki Iwashima 
Signed-off-by: Lorenz Bauer 
Link: https://lore.kernel.org/r/20230720-so-reuseport-v6-1-7021b683cdae@isovalent.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

ipv6: remove hard coded limitation on ipv6_pinfo

2023-09-02T07:13:30+00:00

commit f5f80e32de12fad2813d37270e8364a03e6d3ef0 upstream.

IPv6 inet sockets are supposed to have a "struct ipv6_pinfo"
field at the end of their definition, so that inet6_sk_generic()
can derive from socket size the offset of the "struct ipv6_pinfo".

This is very fragile, and prevents adding bigger alignment
in sockets, because inet6_sk_generic() does not work
if the compiler adds padding after the ipv6_pinfo component.

We are currently working on a patch series to reorganize
TCP structures for better data locality and found issues
similar to the one fixed in commit f5d547676ca0
("tcp: fix tcp_inet6_sk() for 32bit kernels")

Alternative would be to force an alignment on "struct ipv6_pinfo",
greater or equal to __alignof__(any ipv6 sock) to ensure there is
no padding. This does not look great.

v2: fix typo in mptcp_proto_v6_init() (Paolo)

Signed-off-by: Eric Dumazet 
Cc: Chao Wu 
Cc: Wei Wang 
Cc: Coco Li 
Cc: YiFei Zhu 
Reviewed-by: Simon Horman 
Signed-off-by: David S. Miller 
Cc: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman