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8,494 commits

Author SHA1 Message Date
Ido Schimmel
f4fea25f5c ipv6: Do not consider link down nexthops in path selection
[ Upstream commit 8b8e0dd357 ]

Nexthops whose link is down are not supposed to be considered during
path selection when the "ignore_routes_with_linkdown" sysctl is set.
This is done by assigning them a negative region boundary.

However, when comparing the computed hash (unsigned) with the region
boundary (signed), the negative region boundary is treated as unsigned,
resulting in incorrect nexthop selection.

Fix by treating the computed hash as signed. Note that the computed hash
is always in range of [0, 2^31 - 1].

Fixes: 3d709f69a3 ("ipv6: Use hash-threshold instead of modulo-N")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250402114224.293392-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:34 +02:00
Ido Schimmel
1eb36a2cdf ipv6: Start path selection from the first nexthop
[ Upstream commit 4d0ab3a688 ]

Cited commit transitioned IPv6 path selection to use hash-threshold
instead of modulo-N. With hash-threshold, each nexthop is assigned a
region boundary in the multipath hash function's output space and a
nexthop is chosen if the calculated hash is smaller than the nexthop's
region boundary.

Hash-threshold does not work correctly if path selection does not start
with the first nexthop. For example, if fib6_select_path() is always
passed the last nexthop in the group, then it will always be chosen
because its region boundary covers the entire hash function's output
space.

Fix this by starting the selection process from the first nexthop and do
not consider nexthops for which rt6_score_route() provided a negative
score.

Fixes: 3d709f69a3 ("ipv6: Use hash-threshold instead of modulo-N")
Reported-by: Stanislav Fomichev <stfomichev@gmail.com>
Closes: https://lore.kernel.org/netdev/Z9RIyKZDNoka53EO@mini-arch/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250402114224.293392-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:34 +02:00
Fernando Fernandez Mancera
de579015d1 ipv6: fix omitted netlink attributes when using RTEXT_FILTER_SKIP_STATS
[ Upstream commit 7ac6ea4a3e ]

Using RTEXT_FILTER_SKIP_STATS is incorrectly skipping non-stats IPv6
netlink attributes on link dump. This causes issues on userspace tools,
e.g iproute2 is not rendering address generation mode as it should due
to missing netlink attribute.

Move the filling of IFLA_INET6_STATS and IFLA_INET6_ICMP6STATS to a
helper function guarded by a flag check to avoid hitting the same
situation in the future.

Fixes: d5566fd72e ("rtnetlink: RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats")
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250402121751.3108-1-ffmancera@riseup.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:34 +02:00
Debin Zhu
3ba9cf69de netlabel: Fix NULL pointer exception caused by CALIPSO on IPv4 sockets
[ Upstream commit 078aabd567 ]

When calling netlbl_conn_setattr(), addr->sa_family is used
to determine the function behavior. If sk is an IPv4 socket,
but the connect function is called with an IPv6 address,
the function calipso_sock_setattr() is triggered.
Inside this function, the following code is executed:

sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;

Since sk is an IPv4 socket, pinet6 is NULL, leading to a
null pointer dereference.

This patch fixes the issue by checking if inet6_sk(sk)
returns a NULL pointer before accessing pinet6.

Signed-off-by: Debin Zhu <mowenroot@163.com>
Signed-off-by: Bitao Ouyang <1985755126@qq.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Fixes: ceba1832b1 ("calipso: Set the calipso socket label to match the secattr.")
Link: https://patch.msgid.link/20250401124018.4763-1-mowenroot@163.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-10 14:39:33 +02:00
Maxim Mikityanskiy
2bb139e483 netfilter: socket: Lookup orig tuple for IPv6 SNAT
commit 932b32ffd7 upstream.

nf_sk_lookup_slow_v4 does the conntrack lookup for IPv4 packets to
restore the original 5-tuple in case of SNAT, to be able to find the
right socket (if any). Then socket_match() can correctly check whether
the socket was transparent.

However, the IPv6 counterpart (nf_sk_lookup_slow_v6) lacks this
conntrack lookup, making xt_socket fail to match on the socket when the
packet was SNATed. Add the same logic to nf_sk_lookup_slow_v6.

IPv6 SNAT is used in Kubernetes clusters for pod-to-world packets, as
pods' addresses are in the fd00::/8 ULA subnet and need to be replaced
with the node's external address. Cilium leverages Envoy to enforce L7
policies, and Envoy uses transparent sockets. Cilium inserts an iptables
prerouting rule that matches on `-m socket --transparent` and redirects
the packets to localhost, but it fails to match SNATed IPv6 packets due
to that missing conntrack lookup.

Closes: https://github.com/cilium/cilium/issues/37932
Fixes: eb31628e37 ("netfilter: nf_tables: Add support for IPv6 NAT")
Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-07 10:08:35 +02:00
Guillaume Nault
a3ff812d68 Revert "gre: Fix IPv6 link-local address generation."
[ Upstream commit fc486c2d06 ]

This reverts commit 183185a18f.

This patch broke net/forwarding/ip6gre_custom_multipath_hash.sh in some
circumstances (https://lore.kernel.org/netdev/Z9RIyKZDNoka53EO@mini-arch/).
Let's revert it while the problem is being investigated.

Fixes: 183185a18f ("gre: Fix IPv6 link-local address generation.")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Link: https://patch.msgid.link/8b1ce738eb15dd841aab9ef888640cab4f6ccfea.1742418408.git.gnault@redhat.com
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-28 22:03:28 +01:00
Justin Iurman
0d8a8179fa net: ipv6: ioam6: fix lwtunnel_output() loop
[ Upstream commit 3e7a60b368 ]

Fix the lwtunnel_output() reentry loop in ioam6_iptunnel when the
destination is the same after transformation. Note that a check on the
destination address was already performed, but it was not enough. This
is the example of a lwtunnel user taking care of loops without relying
only on the last resort detection offered by lwtunnel.

Fixes: 8cb3bf8bff ("ipv6: ioam: Add support for the ip6ip6 encapsulation")
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250314120048.12569-3-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-28 22:03:28 +01:00
Kuniyuki Iwashima
cfbde06fda ipv6: Set errno after ip_fib_metrics_init() in ip6_route_info_create().
[ Upstream commit 9a81fc3480 ]

While creating a new IPv6, we could get a weird -ENOMEM when
RTA_NH_ID is set and either of the conditions below is true:

  1) CONFIG_IPV6_SUBTREES is enabled and rtm_src_len is specified
  2) nexthop_get() fails

e.g.)

  # strace ip -6 route add fe80::dead:beef:dead:beef nhid 1 from ::
  recvmsg(3, {msg_iov=[{iov_base=[...[
    {error=-ENOMEM, msg=[... [...]]},
    [{nla_len=49, nla_type=NLMSGERR_ATTR_MSG}, "Nexthops can not be used with so"...]
  ]], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 148

Let's set err explicitly after ip_fib_metrics_init() in
ip6_route_info_create().

Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250312013854.61125-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-28 22:03:27 +01:00
Kuniyuki Iwashima
29d9182018 ipv6: Fix memleak of nhc_pcpu_rth_output in fib_check_nh_v6_gw().
[ Upstream commit 9740890ee2 ]

fib_check_nh_v6_gw() expects that fib6_nh_init() cleans up everything
when it fails.

Commit 7dd73168e2 ("ipv6: Always allocate pcpu memory in a fib6_nh")
moved fib_nh_common_init() before alloc_percpu_gfp() within fib6_nh_init()
but forgot to add cleanup for fib6_nh->nh_common.nhc_pcpu_rth_output in
case it fails to allocate fib6_nh->rt6i_pcpu, resulting in memleak.

Let's call fib_nh_common_release() and clear nhc_pcpu_rth_output in the
error path.

Note that we can remove the fib6_nh_release() call in nh_create_ipv6()
later in net-next.git.

Fixes: 7dd73168e2 ("ipv6: Always allocate pcpu memory in a fib6_nh")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250312010333.56001-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-28 22:03:27 +01:00
Felix Fietkau
8940e6168b net: ipv6: fix TCP GSO segmentation with NAT
[ Upstream commit daa624d3c2 ]

When updating the source/destination address, the TCP/UDP checksum needs to
be updated as well.

Fixes: bee88cd5bd ("net: add support for segmenting TCP fraglist GSO packets")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/20250311212530.91519-1-nbd@nbd.name
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-28 22:03:27 +01:00
Guillaume Nault
a4d42b5901 gre: Fix IPv6 link-local address generation.
[ Upstream commit 183185a18f ]

Use addrconf_addr_gen() to generate IPv6 link-local addresses on GRE
devices in most cases and fall back to using add_v4_addrs() only in
case the GRE configuration is incompatible with addrconf_addr_gen().

GRE used to use addrconf_addr_gen() until commit e5dd729460
("ip/ip6_gre: use the same logic as SIT interfaces when computing v6LL
address") restricted this use to gretap and ip6gretap devices, and
created add_v4_addrs() (borrowed from SIT) for non-Ethernet GRE ones.

The original problem came when commit 9af28511be ("addrconf: refuse
isatap eui64 for INADDR_ANY") made __ipv6_isatap_ifid() fail when its
addr parameter was 0. The commit says that this would create an invalid
address, however, I couldn't find any RFC saying that the generated
interface identifier would be wrong. Anyway, since gre over IPv4
devices pass their local tunnel address to __ipv6_isatap_ifid(), that
commit broke their IPv6 link-local address generation when the local
address was unspecified.

Then commit e5dd729460 ("ip/ip6_gre: use the same logic as SIT
interfaces when computing v6LL address") tried to fix that case by
defining add_v4_addrs() and calling it to generate the IPv6 link-local
address instead of using addrconf_addr_gen() (apart for gretap and
ip6gretap devices, which would still use the regular
addrconf_addr_gen(), since they have a MAC address).

That broke several use cases because add_v4_addrs() isn't properly
integrated into the rest of IPv6 Neighbor Discovery code. Several of
these shortcomings have been fixed over time, but add_v4_addrs()
remains broken on several aspects. In particular, it doesn't send any
Router Sollicitations, so the SLAAC process doesn't start until the
interface receives a Router Advertisement. Also, add_v4_addrs() mostly
ignores the address generation mode of the interface
(/proc/sys/net/ipv6/conf/*/addr_gen_mode), thus breaking the
IN6_ADDR_GEN_MODE_RANDOM and IN6_ADDR_GEN_MODE_STABLE_PRIVACY cases.

Fix the situation by using add_v4_addrs() only in the specific scenario
where the normal method would fail. That is, for interfaces that have
all of the following characteristics:

  * run over IPv4,
  * transport IP packets directly, not Ethernet (that is, not gretap
    interfaces),
  * tunnel endpoint is INADDR_ANY (that is, 0),
  * device address generation mode is EUI64.

In all other cases, revert back to the regular addrconf_addr_gen().

Also, remove the special case for ip6gre interfaces in add_v4_addrs(),
since ip6gre devices now always use addrconf_addr_gen() instead.

Fixes: e5dd729460 ("ip/ip6_gre: use the same logic as SIT interfaces when computing v6LL address")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/559c32ce5c9976b269e6337ac9abb6a96abe5096.1741375285.git.gnault@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-22 12:54:13 -07:00
Justin Iurman
cc9a0b498b net: ipv6: fix missing dst ref drop in ila lwtunnel
[ Upstream commit 5da15a9c11 ]

Add missing skb_dst_drop() to drop reference to the old dst before
adding the new dst to the skb.

Fixes: 79ff2fc31e ("ila: Cache a route to translated address")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250305081655.19032-1-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 13:02:09 +01:00
Justin Iurman
a3bf9969e2 net: ipv6: fix dst ref loop in ila lwtunnel
[ Upstream commit 0e7633d7b9 ]

This patch follows commit 92191dd107 ("net: ipv6: fix dst ref loops in
rpl, seg6 and ioam6 lwtunnels") and, on a second thought, the same patch
is also needed for ila (even though the config that triggered the issue
was pathological, but still, we don't want that to happen).

Fixes: 79ff2fc31e ("ila: Cache a route to translated address")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Link: https://patch.msgid.link/20250304181039.35951-1-justin.iurman@uliege.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-13 13:02:09 +01:00
Justin Iurman
51946f3242 net: ipv6: fix dst ref loop on input in rpl lwt
[ Upstream commit 13e55fbaec ]

Prevent a dst ref loop on input in rpl_iptunnel.

Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:33 +01:00
Justin Iurman
bc9ca8a185 net: ipv6: fix dst ref loop on input in seg6 lwt
[ Upstream commit c64a0727f9 ]

Prevent a dst ref loop on input in seg6_iptunnel.

Fixes: af4a2209b1 ("ipv6: sr: use dst_cache in seg6_input")
Cc: David Lebrun <dlebrun@google.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:33 +01:00
Guillaume Nault
97c455c3c2 ipv4: Convert ip_route_input() to dscp_t.
[ Upstream commit 7e863e5db6 ]

Pass a dscp_t variable to ip_route_input(), instead of a plain u8, to
prevent accidental setting of ECN bits in ->flowi4_tos.

Callers of ip_route_input() to consider are:

  * input_action_end_dx4_finish() and input_action_end_dt4() in
    net/ipv6/seg6_local.c. These functions set the tos parameter to 0,
    which is already a valid dscp_t value, so they don't need to be
    adjusted for the new prototype.

  * icmp_route_lookup(), which already has a dscp_t variable to pass as
    parameter. We just need to remove the inet_dscp_to_dsfield()
    conversion.

  * br_nf_pre_routing_finish(), ip_options_rcv_srr() and ip4ip6_err(),
    which get the DSCP directly from IPv4 headers. Define a helper to
    read the .tos field of struct iphdr as dscp_t, so that these
    function don't have to do the conversion manually.

While there, declare *iph as const in br_nf_pre_routing_finish(),
declare its local variables in reverse-christmas-tree order and move
the "err = ip_route_input()" assignment out of the conditional to avoid
checkpatch warning.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/e9d40781d64d3d69f4c79ac8a008b8d67a033e8d.1727807926.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 27843ce6ba ("ipvlan: ensure network headers are in skb linear part")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-03-07 18:25:29 +01:00
Jakub Kicinski
2248b81450 net: ipv6: fix dst refleaks in rpl, seg6 and ioam6 lwtunnels
commit c71a192976 upstream.

dst_cache_get() gives us a reference, we need to release it.

Discovered by the ioam6.sh test, kmemleak was recently fixed
to catch per-cpu memory leaks.

Fixes: 985ec6f5e6 ("net: ipv6: rpl_iptunnel: mitigate 2-realloc issue")
Fixes: 40475b6376 ("net: ipv6: seg6_iptunnel: mitigate 2-realloc issue")
Fixes: dce525185b ("net: ipv6: ioam6_iptunnel: mitigate 2-realloc issue")
Reviewed-by: Justin Iurman <justin.iurman@uliege.be>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250130031519.2716843-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-21 14:01:46 +01:00
Eric Dumazet
25195f9d5f ipv6: mcast: add RCU protection to mld_newpack()
[ Upstream commit a527750d87 ]

mld_newpack() can be called without RTNL or RCU being held.

Note that we no longer can use sock_alloc_send_skb() because
ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.

Instead use alloc_skb() and charge the net->ipv6.igmp_sk
socket under RCU protection.

Fixes: b8ad0cbc58 ("[NETNS][IPV6] mcast - handle several network namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250212141021.1663666-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:44 +01:00
Eric Dumazet
0bf8e2f376 ipv6: mcast: extend RCU protection in igmp6_send()
[ Upstream commit 087c1faa59 ]

igmp6_send() can be called without RTNL or RCU being held.

Extend RCU protection so that we can safely fetch the net pointer
and avoid a potential UAF.

Note that we no longer can use sock_alloc_send_skb() because
ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep.

Instead use alloc_skb() and charge the net->ipv6.igmp_sk
socket under RCU protection.

Fixes: b8ad0cbc58 ("[NETNS][IPV6] mcast - handle several network namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250207135841.1948589-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:43 +01:00
Eric Dumazet
789230e5a8 ndisc: extend RCU protection in ndisc_send_skb()
[ Upstream commit ed6ae1f325 ]

ndisc_send_skb() can be called without RTNL or RCU held.

Acquire rcu_read_lock() earlier, so that we can use dev_net_rcu()
and avoid a potential UAF.

Fixes: 1762f7e88e ("[NETNS][IPV6] ndisc - make socket control per namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250207135841.1948589-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:43 +01:00
Eric Dumazet
bbec88e410 ndisc: use RCU protection in ndisc_alloc_skb()
[ Upstream commit 628e6d1893 ]

ndisc_alloc_skb() can be called without RTNL or RCU being held.

Add RCU protection to avoid possible UAF.

Fixes: de09334b93 ("ndisc: Introduce ndisc_alloc_skb() helper.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250207135841.1948589-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:42 +01:00
Eric Dumazet
653bb5225c ipv6: icmp: convert to dev_net_rcu()
[ Upstream commit 34aef2b0ce ]

icmp6_send() must acquire rcu_read_lock() sooner to ensure
the dev_net() call done from a safe context.

Other ICMPv6 uses of dev_net() seem safe, change them to
dev_net_rcu() to get LOCKDEP support to catch bugs.

Fixes: 9a43b709a2 ("[NETNS][IPV6] icmp6 - make icmpv6_socket per namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250205155120.1676781-12-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:42 +01:00
Eric Dumazet
713a40c892 ipv6: use RCU protection in ip6_default_advmss()
[ Upstream commit 3c8ffcd248 ]

ip6_default_advmss() needs rcu protection to make
sure the net structure it reads does not disappear.

Fixes: 5578689a4e ("[NETNS][IPV6] route6 - make route6 per namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250205155120.1676781-11-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:42 +01:00
Jakub Kicinski
5ab11a4e21 net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels
[ Upstream commit 92191dd107 ]

Some lwtunnels have a dst cache for post-transformation dst.
If the packet destination did not change we may end up recording
a reference to the lwtunnel in its own cache, and the lwtunnel
state will never be freed.

Discovered by the ioam6.sh test, kmemleak was recently fixed
to catch per-cpu memory leaks. I'm not sure if rpl and seg6
can actually hit this, but in principle I don't see why not.

Fixes: 8cb3bf8bff ("ipv6: ioam: Add support for the ip6ip6 encapsulation")
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Fixes: a7a29f9c36 ("net: ipv6: add rpl sr tunnel")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250130031519.2716843-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:38 +01:00
Justin Iurman
4a855c5aec net: ipv6: rpl_iptunnel: mitigate 2-realloc issue
[ Upstream commit 985ec6f5e6 ]

This patch mitigates the two-reallocations issue with rpl_iptunnel by
providing the dst_entry (in the cache) to the first call to
skb_cow_head(). As a result, the very first iteration would still
trigger two reallocations (i.e., empty cache), while next iterations
would only trigger a single reallocation.

Performance tests before/after applying this patch, which clearly shows
there is no impact (it even shows improvement):
- before: https://ibb.co/nQJhqwc
- after: https://ibb.co/4ZvW6wV

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Cc: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 92191dd107 ("net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:38 +01:00
Justin Iurman
2fcc9f3798 net: ipv6: seg6_iptunnel: mitigate 2-realloc issue
[ Upstream commit 40475b6376 ]

This patch mitigates the two-reallocations issue with seg6_iptunnel by
providing the dst_entry (in the cache) to the first call to
skb_cow_head(). As a result, the very first iteration would still
trigger two reallocations (i.e., empty cache), while next iterations
would only trigger a single reallocation.

Performance tests before/after applying this patch, which clearly shows
the improvement:
- before: https://ibb.co/3Cg4sNH
- after: https://ibb.co/8rQ350r

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Cc: David Lebrun <dlebrun@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 92191dd107 ("net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:38 +01:00
Justin Iurman
8471e22844 net: ipv6: ioam6_iptunnel: mitigate 2-realloc issue
[ Upstream commit dce525185b ]

This patch mitigates the two-reallocations issue with ioam6_iptunnel by
providing the dst_entry (in the cache) to the first call to
skb_cow_head(). As a result, the very first iteration may still trigger
two reallocations (i.e., empty cache), while next iterations would only
trigger a single reallocation.

Performance tests before/after applying this patch, which clearly shows
the improvement:
- inline mode:
  - before: https://ibb.co/LhQ8V63
  - after: https://ibb.co/x5YT2bS
- encap mode:
  - before: https://ibb.co/3Cjm5m0
  - after: https://ibb.co/TwpsxTC
- encap mode with tunsrc:
  - before: https://ibb.co/Gpy9QPg
  - after: https://ibb.co/PW1bZFT

This patch also fixes an incorrect behavior: after the insertion, the
second call to skb_cow_head() makes sure that the dev has enough
headroom in the skb for layer 2 and stuff. In that case, the "old"
dst_entry was used, which is now fixed. After discussing with Paolo, it
appears that both patches can be merged into a single one -this one-
(for the sake of readability) and target net-next.

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: 92191dd107 ("net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:38 +01:00
Eric Dumazet
18e77fccfc ndisc: ndisc_send_redirect() must use dev_get_by_index_rcu()
[ Upstream commit 48145a57d4 ]

ndisc_send_redirect() is called under RCU protection, not RTNL.

It must use dev_get_by_index_rcu() instead of __dev_get_by_index()

Fixes: 2f17becfbe ("vrf: check the original netdevice for generating redirect")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250207135841.1948589-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21 14:01:16 +01:00
Yan Zhai
83ebf741aa udp: gso: do not drop small packets when PMTU reduces
[ Upstream commit 235174b2be ]

Commit 4094871db1 ("udp: only do GSO if # of segs > 1") avoided GSO
for small packets. But the kernel currently dismisses GSO requests only
after checking MTU/PMTU on gso_size. This means any packets, regardless
of their payload sizes, could be dropped when PMTU becomes smaller than
requested gso_size. We encountered this issue in production and it
caused a reliability problem that new QUIC connection cannot be
established before PMTU cache expired, while non GSO sockets still
worked fine at the same time.

Ideally, do not check any GSO related constraints when payload size is
smaller than requested gso_size, and return EMSGSIZE instead of EINVAL
on MTU/PMTU check failure to be more specific on the error cause.

Fixes: 4094871db1 ("udp: only do GSO if # of segs > 1")
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-17 10:05:00 +01:00
Steffen Klassert
5e4334dc39 xfrm: Add an inbound percpu state cache.
[ Upstream commit 81a331a0e7 ]

Now that we can have percpu xfrm states, the number of active
states might increase. To get a better lookup performance,
we add a percpu cache to cache the used inbound xfrm states.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Tested-by: Antony Antony <antony.antony@secunet.com>
Tested-by: Tobias Brunner <tobias@strongswan.org>
Stable-dep-of: e952837f3d ("xfrm: state: fix out-of-bounds read during lookup")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:58:00 +01:00
Eric Dumazet
3d72635127 inet: ipmr: fix data-races
[ Upstream commit 3440fa34ad ]

Following fields of 'struct mr_mfc' can be updated
concurrently (no lock protection) from ip_mr_forward()
and ip6_mr_forward()

- bytes
- pkt
- wrong_if
- lastuse

They also can be read from other functions.

Convert bytes, pkt and wrong_if to atomic_long_t,
and use READ_ONCE()/WRITE_ONCE() for lastuse.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250114221049.1190631-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:23 +01:00
Stefano Brivio
4f8344fce9 udp: Deal with race between UDP socket address change and rehash
[ Upstream commit a502ea6fa9 ]

If a UDP socket changes its local address while it's receiving
datagrams, as a result of connect(), there is a period during which
a lookup operation might fail to find it, after the address is changed
but before the secondary hash (port and address) and the four-tuple
hash (local and remote ports and addresses) are updated.

Secondary hash chains were introduced by commit 30fff9231f ("udp:
bind() optimisation") and, as a result, a rehash operation became
needed to make a bound socket reachable again after a connect().

This operation was introduced by commit 719f835853 ("udp: add
rehash on connect()") which isn't however a complete fix: the
socket will be found once the rehashing completes, but not while
it's pending.

This is noticeable with a socat(1) server in UDP4-LISTEN mode, and a
client sending datagrams to it. After the server receives the first
datagram (cf. _xioopen_ipdgram_listen()), it issues a connect() to
the address of the sender, in order to set up a directed flow.

Now, if the client, running on a different CPU thread, happens to
send a (subsequent) datagram while the server's socket changes its
address, but is not rehashed yet, this will result in a failed
lookup and a port unreachable error delivered to the client, as
apparent from the following reproducer:

  LEN=$(($(cat /proc/sys/net/core/wmem_default) / 4))
  dd if=/dev/urandom bs=1 count=${LEN} of=tmp.in

  while :; do
  	taskset -c 1 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc &
  	sleep 0.1 || sleep 1
  	taskset -c 2 socat OPEN:tmp.in UDP4:localhost:1337,shut-null
  	wait
  done

where the client will eventually get ECONNREFUSED on a write()
(typically the second or third one of a given iteration):

  2024/11/13 21:28:23 socat[46901] E write(6, 0x556db2e3c000, 8192): Connection refused

This issue was first observed as a seldom failure in Podman's tests
checking UDP functionality while using pasta(1) to connect the
container's network namespace, which leads us to a reproducer with
the lookup error resulting in an ICMP packet on a tap device:

  LOCAL_ADDR="$(ip -j -4 addr show|jq -rM '.[] | .addr_info[0] | select(.scope == "global").local')"

  while :; do
  	./pasta --config-net -p pasta.pcap -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc &
  	sleep 0.2 || sleep 1
  	socat OPEN:tmp.in UDP4:${LOCAL_ADDR}:1337,shut-null
  	wait
  	cmp tmp.in tmp.out
  done

Once this fails:

  tmp.in tmp.out differ: char 8193, line 29

we can finally have a look at what's going on:

  $ tshark -r pasta.pcap
      1   0.000000           :: ? ff02::16     ICMPv6 110 Multicast Listener Report Message v2
      2   0.168690 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
      3   0.168767 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
      4   0.168806 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
      5   0.168827 c6:47:05:8d:dc:04 ? Broadcast    ARP 42 Who has 88.198.0.161? Tell 88.198.0.164
      6   0.168851 9a:55:9a:55:9a:55 ? c6:47:05:8d:dc:04 ARP 42 88.198.0.161 is at 9a:55:9a:55:9a:55
      7   0.168875 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
      8   0.168896 88.198.0.164 ? 88.198.0.161 ICMP 590 Destination unreachable (Port unreachable)
      9   0.168926 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
     10   0.168959 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192
     11   0.168989 88.198.0.161 ? 88.198.0.164 UDP 4138 60260 ? 1337 Len=4096
     12   0.169010 88.198.0.161 ? 88.198.0.164 UDP 42 60260 ? 1337 Len=0

On the third datagram received, the network namespace of the container
initiates an ARP lookup to deliver the ICMP message.

In another variant of this reproducer, starting the client with:

  strace -f pasta --config-net -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc 2>strace.log &

and connecting to the socat server using a loopback address:

  socat OPEN:tmp.in UDP4:localhost:1337,shut-null

we can more clearly observe a sendmmsg() call failing after the
first datagram is delivered:

  [pid 278012] connect(173, 0x7fff96c95fc0, 16) = 0
  [...]
  [pid 278012] recvmmsg(173, 0x7fff96c96020, 1024, MSG_DONTWAIT, NULL) = -1 EAGAIN (Resource temporarily unavailable)
  [pid 278012] sendmmsg(173, 0x561c5ad0a720, 1, MSG_NOSIGNAL) = 1
  [...]
  [pid 278012] sendmmsg(173, 0x561c5ad0a720, 1, MSG_NOSIGNAL) = -1 ECONNREFUSED (Connection refused)

and, somewhat confusingly, after a connect() on the same socket
succeeded.

Until commit 4cdeeee925 ("net: udp: prefer listeners bound to an
address"), the race between receive address change and lookup didn't
actually cause visible issues, because, once the lookup based on the
secondary hash chain failed, we would still attempt a lookup based on
the primary hash (destination port only), and find the socket with the
outdated secondary hash.

That change, however, dropped port-only lookups altogether, as side
effect, making the race visible.

To fix this, while avoiding the need to make address changes and
rehash atomic against lookups, reintroduce primary hash lookups as
fallback, if lookups based on four-tuple and secondary hashes fail.

To this end, introduce a simplified lookup implementation, which
doesn't take care of SO_REUSEPORT groups: if we have one, there are
multiple sockets that would match the four-tuple or secondary hash,
meaning that we can't run into this race at all.

v2:
  - instead of synchronising lookup operations against address change
    plus rehash, reintroduce a simplified version of the original
    primary hash lookup as fallback

v1:
  - fix build with CONFIG_IPV6=n: add ifdef around sk_v6_rcv_saddr
    usage (Kuniyuki Iwashima)
  - directly use sk_rcv_saddr for IPv4 receive addresses instead of
    fetching inet_rcv_saddr (Kuniyuki Iwashima)
  - move inet_update_saddr() to inet_hashtables.h and use that
    to set IPv4/IPv6 addresses as suitable (Kuniyuki Iwashima)
  - rebase onto net-next, update commit message accordingly

Reported-by: Ed Santiago <santiago@redhat.com>
Link: https://github.com/containers/podman/issues/24147
Analysed-by: David Gibson <david@gibson.dropbear.id.au>
Fixes: 30fff9231f ("udp: bind() optimisation")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:07 +01:00
Eric Dumazet
9345b588f8 inetpeer: do not get a refcount in inet_getpeer()
[ Upstream commit a853c60950 ]

All inet_getpeer() callers except ip4_frag_init() don't need
to acquire a permanent refcount on the inetpeer.

They can switch to full RCU protection.

Move the refcount_inc_not_zero() into ip4_frag_init(),
so that all the other callers no longer have to
perform a pair of expensive atomic operations on
a possibly contended cache line.

inet_putpeer() no longer needs to be exported.

After this patch, my DUT can receive 8,400,000 UDP packets
per second targeting closed ports, using 50% less cpu cycles
than before.

Also change two calls to l3mdev_master_ifindex() by
l3mdev_master_ifindex_rcu() (Ido ideas)

Fixes: 8c2bd38b95 ("icmp: change the order of rate limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241215175629.1248773-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:06 +01:00
Eric Dumazet
d474a73856 inetpeer: remove create argument of inet_getpeer_v[46]()
[ Upstream commit 661cd8fc8e ]

All callers of inet_getpeer_v4() and inet_getpeer_v6()
want to create an inetpeer.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241215175629.1248773-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: a853c60950 ("inetpeer: do not get a refcount in inet_getpeer()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08 09:57:06 +01:00
Eric Dumazet
3d1b63cf46 ila: serialize calls to nf_register_net_hooks()
[ Upstream commit 260466b576 ]

syzbot found a race in ila_add_mapping() [1]

commit 031ae72825 ("ila: call nf_unregister_net_hooks() sooner")
attempted to fix a similar issue.

Looking at the syzbot repro, we have concurrent ILA_CMD_ADD commands.

Add a mutex to make sure at most one thread is calling nf_register_net_hooks().

[1]
 BUG: KASAN: slab-use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline]
 BUG: KASAN: slab-use-after-free in __rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604
Read of size 4 at addr ffff888028f40008 by task dhcpcd/5501

CPU: 1 UID: 0 PID: 5501 Comm: dhcpcd Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
  __dump_stack lib/dump_stack.c:94 [inline]
  dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
  print_address_description mm/kasan/report.c:378 [inline]
  print_report+0xc3/0x620 mm/kasan/report.c:489
  kasan_report+0xd9/0x110 mm/kasan/report.c:602
  rht_key_hashfn include/linux/rhashtable.h:159 [inline]
  __rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604
  rhashtable_lookup include/linux/rhashtable.h:646 [inline]
  rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline]
  ila_lookup_wildcards net/ipv6/ila/ila_xlat.c:127 [inline]
  ila_xlat_addr net/ipv6/ila/ila_xlat.c:652 [inline]
  ila_nf_input+0x1ee/0x620 net/ipv6/ila/ila_xlat.c:185
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626
  nf_hook.constprop.0+0x42e/0x750 include/linux/netfilter.h:269
  NF_HOOK include/linux/netfilter.h:312 [inline]
  ipv6_rcv+0xa4/0x680 net/ipv6/ip6_input.c:309
  __netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5672
  __netif_receive_skb+0x1d/0x160 net/core/dev.c:5785
  process_backlog+0x443/0x15f0 net/core/dev.c:6117
  __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6883
  napi_poll net/core/dev.c:6952 [inline]
  net_rx_action+0xa94/0x1010 net/core/dev.c:7074
  handle_softirqs+0x213/0x8f0 kernel/softirq.c:561
  __do_softirq kernel/softirq.c:595 [inline]
  invoke_softirq kernel/softirq.c:435 [inline]
  __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
  sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049

Fixes: 7f00feaf10 ("ila: Add generic ILA translation facility")
Reported-by: syzbot+47e761d22ecf745f72b9@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6772c9ae.050a0220.2f3838.04c7.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Tom Herbert <tom@herbertland.com>
Link: https://patch.msgid.link/20241230162849.2795486-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:33:42 +01:00
Dmitry Safonov
051f49d517 net/tcp: Add missing lockdep annotations for TCP-AO hlist traversals
[ Upstream commit 6b2d11e2d8 ]

Under CONFIG_PROVE_RCU_LIST + CONFIG_RCU_EXPERT
hlist_for_each_entry_rcu() provides very helpful splats, which help
to find possible issues. I missed CONFIG_RCU_EXPERT=y in my testing
config the same as described in
a3e4bf7f96 ("configs/debug: make sure PROVE_RCU_LIST=y takes effect").

The fix itself is trivial: add the very same lockdep annotations
as were used to dereference ao_info from the socket.

Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://lore.kernel.org/netdev/20241028152645.35a8be66@kernel.org/
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20241030-tcp-ao-hlist-lockdep-annotate-v1-1-bf641a64d7c6@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 20:03:53 +01:00
Ignat Korchagin
f44fceb71d net: inet6: do not leave a dangling sk pointer in inet6_create()
[ Upstream commit 9df99c395d ]

sock_init_data() attaches the allocated sk pointer to the provided sock
object. If inet6_create() fails later, the sk object is released, but the
sock object retains the dangling sk pointer, which may cause use-after-free
later.

Clear the sock sk pointer on error.

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241014153808.51894-8-ignat@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 20:03:48 +01:00
Jiri Wiesner
8b591bd522 net/ipv6: release expired exception dst cached in socket
[ Upstream commit 3301ab7d5a ]

Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
  resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
  start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
  before TCP executes ip6_negative_advice() for the expired exception dst

When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.

As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf86 ("ipv6: give an IPv6 dev to blackhole_netdev"):
unregister_netdevice: waiting for lo to become free. Usage count = 2

Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2 ("net: fix __dst_negative_advice() race"). But 92f1655aa2
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2. The bug was introduced in
54c1a859ef ("ipv6: Don't drop cache route entry unless timer actually
expired.") where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.

The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.

Fixes: 92f1655aa2 ("net: fix __dst_negative_advice() race")
Fixes: 54c1a859ef ("ipv6: Don't drop cache route entry unless timer actually expired.")
Link: https://lore.kernel.org/netdev/20241113105611.GA6723@incl/T/#u
Signed-off-by: Jiri Wiesner <jwiesner@suse.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241128085950.GA4505@incl
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 20:03:05 +01:00
Eric Dumazet
01f95357e4 ipv6: avoid possible NULL deref in modify_prefix_route()
[ Upstream commit a747e02430 ]

syzbot found a NULL deref [1] in modify_prefix_route(), caused by one
fib6_info without a fib6_table pointer set.

This can happen for net->ipv6.fib6_null_entry

[1]
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 1 UID: 0 PID: 5837 Comm: syz-executor888 Not tainted 6.12.0-syzkaller-09567-g7eef7e306d3c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
 RIP: 0010:__lock_acquire+0xe4/0x3c40 kernel/locking/lockdep.c:5089
Code: 08 84 d2 0f 85 15 14 00 00 44 8b 0d ca 98 f5 0e 45 85 c9 0f 84 b4 0e 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 96 2c 00 00 49 8b 04 24 48 3d a0 07 7f 93 0f 84
RSP: 0018:ffffc900035d7268 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000006 RSI: 1ffff920006bae5f RDI: 0000000000000030
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90608e17 R11: 0000000000000001 R12: 0000000000000030
R13: ffff888036334880 R14: 0000000000000000 R15: 0000000000000000
FS:  0000555579e90380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc59cc4278 CR3: 0000000072b54000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
  __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
  _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
  spin_lock_bh include/linux/spinlock.h:356 [inline]
  modify_prefix_route+0x30b/0x8b0 net/ipv6/addrconf.c:4831
  inet6_addr_modify net/ipv6/addrconf.c:4923 [inline]
  inet6_rtm_newaddr+0x12c7/0x1ab0 net/ipv6/addrconf.c:5055
  rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6920
  netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2541
  netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
  netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1347
  netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1891
  sock_sendmsg_nosec net/socket.c:711 [inline]
  __sock_sendmsg net/socket.c:726 [inline]
  ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2583
  ___sys_sendmsg+0x135/0x1e0 net/socket.c:2637
  __sys_sendmsg+0x16e/0x220 net/socket.c:2669
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1dcef8b79
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc59cc4378 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd1dcef8b79
RDX: 0000000000040040 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00000000000113fd R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffc59cc438c
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Fixes: 5eb902b8e7 ("net/ipv6: Remove expired routes with a separated list of routes.")
Reported-by: syzbot+1de74b0794c40c8eb300@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67461f7f.050a0220.1286eb.0021.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
CC: Kui-Feng Lee <thinker.li@gmail.com>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14 20:03:04 +01:00
Paolo Abeni
ead7c1263e ip6mr: fix tables suspicious RCU usage
[ Upstream commit f1553c9894 ]

Several places call ip6mr_get_table() with no RCU nor RTNL lock.
Add RCU protection inside such helper and provide a lockless variant
for the few callers that already acquired the relevant lock.

Note that some users additionally reference the table outside the RCU
lock. That is actually safe as the table deletion can happen only
after all table accesses are completed.

Fixes: e2d57766e6 ("net: Provide compat support for SIOCGETMIFCNT_IN6 and SIOCGETSGCNT_IN6.")
Fixes: d7c31cbde4 ("net: ip6mr: add RTM_GETROUTE netlink op")
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:35 +01:00
Hangbin Liu
cb74207ef9 net/ipv6: delete temporary address if mngtmpaddr is removed or unmanaged
[ Upstream commit 00b5b7aab9 ]

RFC8981 section 3.4 says that existing temporary addresses must have their
lifetimes adjusted so that no temporary addresses should ever remain "valid"
or "preferred" longer than the incoming SLAAC Prefix Information. This would
strongly imply in Linux's case that if the "mngtmpaddr" address is deleted or
un-flagged as such, its corresponding temporary addresses must be cleared out
right away.

But now the temporary address is renewed even after ‘mngtmpaddr’ is removed
or becomes unmanaged as manage_tempaddrs() set temporary addresses
prefered/valid time to 0, and later in addrconf_verify_rtnl() all checkings
failed to remove the addresses. Fix this by deleting the temporary address
directly for these situations.

Fixes: 778964f2fd ("ipv6/addrconf: fix timing bug in tempaddr regen")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:32 +01:00
Omid Ehtemam-Haghighi
34a949e7a0 ipv6: Fix soft lockups in fib6_select_path under high next hop churn
[ Upstream commit d9ccb18f83 ]

Soft lockups have been observed on a cluster of Linux-based edge routers
located in a highly dynamic environment. Using the `bird` service, these
routers continuously update BGP-advertised routes due to frequently
changing nexthop destinations, while also managing significant IPv6
traffic. The lockups occur during the traversal of the multipath
circular linked-list in the `fib6_select_path` function, particularly
while iterating through the siblings in the list. The issue typically
arises when the nodes of the linked list are unexpectedly deleted
concurrently on a different core—indicated by their 'next' and
'previous' elements pointing back to the node itself and their reference
count dropping to zero. This results in an infinite loop, leading to a
soft lockup that triggers a system panic via the watchdog timer.

Apply RCU primitives in the problematic code sections to resolve the
issue. Where necessary, update the references to fib6_siblings to
annotate or use the RCU APIs.

Include a test script that reproduces the issue. The script
periodically updates the routing table while generating a heavy load
of outgoing IPv6 traffic through multiple iperf3 clients. It
consistently induces infinite soft lockups within a couple of minutes.

Kernel log:

 0 [ffffbd13003e8d30] machine_kexec at ffffffff8ceaf3eb
 1 [ffffbd13003e8d90] __crash_kexec at ffffffff8d0120e3
 2 [ffffbd13003e8e58] panic at ffffffff8cef65d4
 3 [ffffbd13003e8ed8] watchdog_timer_fn at ffffffff8d05cb03
 4 [ffffbd13003e8f08] __hrtimer_run_queues at ffffffff8cfec62f
 5 [ffffbd13003e8f70] hrtimer_interrupt at ffffffff8cfed756
 6 [ffffbd13003e8fd0] __sysvec_apic_timer_interrupt at ffffffff8cea01af
 7 [ffffbd13003e8ff0] sysvec_apic_timer_interrupt at ffffffff8df1b83d
-- <IRQ stack> --
 8 [ffffbd13003d3708] asm_sysvec_apic_timer_interrupt at ffffffff8e000ecb
    [exception RIP: fib6_select_path+299]
    RIP: ffffffff8ddafe7b  RSP: ffffbd13003d37b8  RFLAGS: 00000287
    RAX: ffff975850b43600  RBX: ffff975850b40200  RCX: 0000000000000000
    RDX: 000000003fffffff  RSI: 0000000051d383e4  RDI: ffff975850b43618
    RBP: ffffbd13003d3800   R8: 0000000000000000   R9: ffff975850b40200
    R10: 0000000000000000  R11: 0000000000000000  R12: ffffbd13003d3830
    R13: ffff975850b436a8  R14: ffff975850b43600  R15: 0000000000000007
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 9 [ffffbd13003d3808] ip6_pol_route at ffffffff8ddb030c
10 [ffffbd13003d3888] ip6_pol_route_input at ffffffff8ddb068c
11 [ffffbd13003d3898] fib6_rule_lookup at ffffffff8ddf02b5
12 [ffffbd13003d3928] ip6_route_input at ffffffff8ddb0f47
13 [ffffbd13003d3a18] ip6_rcv_finish_core.constprop.0 at ffffffff8dd950d0
14 [ffffbd13003d3a30] ip6_list_rcv_finish.constprop.0 at ffffffff8dd96274
15 [ffffbd13003d3a98] ip6_sublist_rcv at ffffffff8dd96474
16 [ffffbd13003d3af8] ipv6_list_rcv at ffffffff8dd96615
17 [ffffbd13003d3b60] __netif_receive_skb_list_core at ffffffff8dc16fec
18 [ffffbd13003d3be0] netif_receive_skb_list_internal at ffffffff8dc176b3
19 [ffffbd13003d3c50] napi_gro_receive at ffffffff8dc565b9
20 [ffffbd13003d3c80] ice_receive_skb at ffffffffc087e4f5 [ice]
21 [ffffbd13003d3c90] ice_clean_rx_irq at ffffffffc0881b80 [ice]
22 [ffffbd13003d3d20] ice_napi_poll at ffffffffc088232f [ice]
23 [ffffbd13003d3d80] __napi_poll at ffffffff8dc18000
24 [ffffbd13003d3db8] net_rx_action at ffffffff8dc18581
25 [ffffbd13003d3e40] __do_softirq at ffffffff8df352e9
26 [ffffbd13003d3eb0] run_ksoftirqd at ffffffff8ceffe47
27 [ffffbd13003d3ec0] smpboot_thread_fn at ffffffff8cf36a30
28 [ffffbd13003d3ee8] kthread at ffffffff8cf2b39f
29 [ffffbd13003d3f28] ret_from_fork at ffffffff8ce5fa64
30 [ffffbd13003d3f50] ret_from_fork_asm at ffffffff8ce03cbb

Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Adrian Oliver <kernel@aoliver.ca>
Signed-off-by: Omid Ehtemam-Haghighi <omid.ehtemamhaghighi@menlosecurity.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ido Schimmel <idosch@idosch.org>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Simon Horman <horms@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241106010236.1239299-1-omid.ehtemamhaghighi@menlosecurity.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:01:57 +01:00
Paolo Abeni
0e4c6faaef ipv6: release nexthop on device removal
[ Upstream commit eb02688c5c ]

The CI is hitting some aperiodic hangup at device removal time in the
pmtu.sh self-test:

unregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 6
ref_tracker: veth_A-R1@ffff888013df15d8 has 1/5 users at
	dst_init+0x84/0x4a0
	dst_alloc+0x97/0x150
	ip6_dst_alloc+0x23/0x90
	ip6_rt_pcpu_alloc+0x1e6/0x520
	ip6_pol_route+0x56f/0x840
	fib6_rule_lookup+0x334/0x630
	ip6_route_output_flags+0x259/0x480
	ip6_dst_lookup_tail.constprop.0+0x5c2/0x940
	ip6_dst_lookup_flow+0x88/0x190
	udp_tunnel6_dst_lookup+0x2a7/0x4c0
	vxlan_xmit_one+0xbde/0x4a50 [vxlan]
	vxlan_xmit+0x9ad/0xf20 [vxlan]
	dev_hard_start_xmit+0x10e/0x360
	__dev_queue_xmit+0xf95/0x18c0
	arp_solicit+0x4a2/0xe00
	neigh_probe+0xaa/0xf0

While the first suspect is the dst_cache, explicitly tracking the dst
owing the last device reference via probes proved such dst is held by
the nexthop in the originating fib6_info.

Similar to commit f5b51fe804 ("ipv6: route: purge exception on
removal"), we need to explicitly release the originating fib info when
disconnecting a to-be-removed device from a live ipv6 dst: move the
fib6_info cleanup into ip6_dst_ifdown().

Tested running:

./pmtu.sh cleanup_ipv6_exception

in a tight loop for more than 400 iterations with no spat, running an
unpatched kernel  I observed a splat every ~10 iterations.

Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/604c45c188c609b732286b47ac2a451a40f6cf6d.1730828007.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:01:55 +01:00
Wang Liang
073d89808c net: fix data-races around sk->sk_forward_alloc
Syzkaller reported this warning:
 ------------[ cut here ]------------
 WARNING: CPU: 0 PID: 16 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x1c5/0x1e0
 Modules linked in:
 CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-rc5 #26
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
 RIP: 0010:inet_sock_destruct+0x1c5/0x1e0
 Code: 24 12 4c 89 e2 5b 48 c7 c7 98 ec bb 82 41 5c e9 d1 18 17 ff 4c 89 e6 5b 48 c7 c7 d0 ec bb 82 41 5c e9 bf 18 17 ff 0f 0b eb 83 <0f> 0b eb 97 0f 0b eb 87 0f 0b e9 68 ff ff ff 66 66 2e 0f 1f 84 00
 RSP: 0018:ffffc9000008bd90 EFLAGS: 00010206
 RAX: 0000000000000300 RBX: ffff88810b172a90 RCX: 0000000000000007
 RDX: 0000000000000002 RSI: 0000000000000300 RDI: ffff88810b172a00
 RBP: ffff88810b172a00 R08: ffff888104273c00 R09: 0000000000100007
 R10: 0000000000020000 R11: 0000000000000006 R12: ffff88810b172a00
 R13: 0000000000000004 R14: 0000000000000000 R15: ffff888237c31f78
 FS:  0000000000000000(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007ffc63fecac8 CR3: 000000000342e000 CR4: 00000000000006f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <TASK>
  ? __warn+0x88/0x130
  ? inet_sock_destruct+0x1c5/0x1e0
  ? report_bug+0x18e/0x1a0
  ? handle_bug+0x53/0x90
  ? exc_invalid_op+0x18/0x70
  ? asm_exc_invalid_op+0x1a/0x20
  ? inet_sock_destruct+0x1c5/0x1e0
  __sk_destruct+0x2a/0x200
  rcu_do_batch+0x1aa/0x530
  ? rcu_do_batch+0x13b/0x530
  rcu_core+0x159/0x2f0
  handle_softirqs+0xd3/0x2b0
  ? __pfx_smpboot_thread_fn+0x10/0x10
  run_ksoftirqd+0x25/0x30
  smpboot_thread_fn+0xdd/0x1d0
  kthread+0xd3/0x100
  ? __pfx_kthread+0x10/0x10
  ret_from_fork+0x34/0x50
  ? __pfx_kthread+0x10/0x10
  ret_from_fork_asm+0x1a/0x30
  </TASK>
 ---[ end trace 0000000000000000 ]---

Its possible that two threads call tcp_v6_do_rcv()/sk_forward_alloc_add()
concurrently when sk->sk_state == TCP_LISTEN with sk->sk_lock unlocked,
which triggers a data-race around sk->sk_forward_alloc:
tcp_v6_rcv
    tcp_v6_do_rcv
        skb_clone_and_charge_r
            sk_rmem_schedule
                __sk_mem_schedule
                    sk_forward_alloc_add()
            skb_set_owner_r
                sk_mem_charge
                    sk_forward_alloc_add()
        __kfree_skb
            skb_release_all
                skb_release_head_state
                    sock_rfree
                        sk_mem_uncharge
                            sk_forward_alloc_add()
                            sk_mem_reclaim
                                // set local var reclaimable
                                __sk_mem_reclaim
                                    sk_forward_alloc_add()

In this syzkaller testcase, two threads call
tcp_v6_do_rcv() with skb->truesize=768, the sk_forward_alloc changes like
this:
 (cpu 1)             | (cpu 2)             | sk_forward_alloc
 ...                 | ...                 | 0
 __sk_mem_schedule() |                     | +4096 = 4096
                     | __sk_mem_schedule() | +4096 = 8192
 sk_mem_charge()     |                     | -768  = 7424
                     | sk_mem_charge()     | -768  = 6656
 ...                 |    ...              |
 sk_mem_uncharge()   |                     | +768  = 7424
 reclaimable=7424    |                     |
                     | sk_mem_uncharge()   | +768  = 8192
                     | reclaimable=8192    |
 __sk_mem_reclaim()  |                     | -4096 = 4096
                     | __sk_mem_reclaim()  | -8192 = -4096 != 0

The skb_clone_and_charge_r() should not be called in tcp_v6_do_rcv() when
sk->sk_state is TCP_LISTEN, it happens later in tcp_v6_syn_recv_sock().
Fix the same issue in dccp_v6_do_rcv().

Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Fixes: e994b2f0fb ("tcp: do not lock listener to process SYN packets")
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20241107023405.889239-1-wangliang74@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-11 15:29:33 -08:00
Eric Dumazet
4ed234fe79 netfilter: nf_reject_ipv6: fix potential crash in nf_send_reset6()
I got a syzbot report without a repro [1] crashing in nf_send_reset6()

I think the issue is that dev->hard_header_len is zero, and we attempt
later to push an Ethernet header.

Use LL_MAX_HEADER, as other functions in net/ipv6/netfilter/nf_reject_ipv6.c.

[1]

skbuff: skb_under_panic: text:ffffffff89b1d008 len:74 put:14 head:ffff88803123aa00 data:ffff88803123a9f2 tail:0x3c end:0x140 dev:syz_tun
 kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 7373 Comm: syz.1.568 Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
 RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0d 8d 48 c7 c6 60 a6 29 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 ba 30 38 02 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc900045269b0 EFLAGS: 00010282
RAX: 0000000000000088 RBX: dffffc0000000000 RCX: cd66dacdc5d8e800
RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000
RBP: ffff88802d39a3d0 R08: ffffffff8174afec R09: 1ffff920008a4ccc
R10: dffffc0000000000 R11: fffff520008a4ccd R12: 0000000000000140
R13: ffff88803123aa00 R14: ffff88803123a9f2 R15: 000000000000003c
FS:  00007fdbee5ff6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005d322000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  skb_push+0xe5/0x100 net/core/skbuff.c:2636
  eth_header+0x38/0x1f0 net/ethernet/eth.c:83
  dev_hard_header include/linux/netdevice.h:3208 [inline]
  nf_send_reset6+0xce6/0x1270 net/ipv6/netfilter/nf_reject_ipv6.c:358
  nft_reject_inet_eval+0x3b9/0x690 net/netfilter/nft_reject_inet.c:48
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK include/linux/netfilter.h:312 [inline]
  br_nf_pre_routing_ipv6+0x63e/0x770 net/bridge/br_netfilter_ipv6.c:184
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_bridge_pre net/bridge/br_input.c:277 [inline]
  br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424
  __netif_receive_skb_core+0x13e8/0x4570 net/core/dev.c:5562
  __netif_receive_skb_one_core net/core/dev.c:5666 [inline]
  __netif_receive_skb+0x12f/0x650 net/core/dev.c:5781
  netif_receive_skb_internal net/core/dev.c:5867 [inline]
  netif_receive_skb+0x1e8/0x890 net/core/dev.c:5926
  tun_rx_batched+0x1b7/0x8f0 drivers/net/tun.c:1550
  tun_get_user+0x3056/0x47e0 drivers/net/tun.c:2007
  tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2053
  new_sync_write fs/read_write.c:590 [inline]
  vfs_write+0xa6d/0xc90 fs/read_write.c:683
  ksys_write+0x183/0x2b0 fs/read_write.c:736
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdbeeb7d1ff
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48
RSP: 002b:00007fdbee5ff000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fdbeed36058 RCX: 00007fdbeeb7d1ff
RDX: 000000000000008e RSI: 0000000020000040 RDI: 00000000000000c8
RBP: 00007fdbeebf12be R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000008e R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdbeed36058 R15: 00007ffc38de06e8
 </TASK>

Fixes: c8d7b98bec ("netfilter: move nf_send_resetX() code to nf_reject_ipvX modules")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-10-30 13:17:36 +01:00
Paolo Abeni
1e424d08d3 ipsec-2024-10-22
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Merge tag 'ipsec-2024-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2024-10-22

1) Fix routing behavior that relies on L4 information
   for xfrm encapsulated packets.
   From Eyal Birger.

2) Remove leftovers of pernet policy_inexact lists.
   From Florian Westphal.

3) Validate new SA's prefixlen when the selector family is
   not set from userspace.
   From Sabrina Dubroca.

4) Fix a kernel-infoleak when dumping an auth algorithm.
   From Petr Vaganov.

Please pull or let me know if there are problems.

ipsec-2024-10-22

* tag 'ipsec-2024-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec:
  xfrm: fix one more kernel-infoleak in algo dumping
  xfrm: validate new SA's prefixlen using SA family when sel.family is unset
  xfrm: policy: remove last remnants of pernet inexact list
  xfrm: respect ip protocols rules criteria when performing dst lookups
  xfrm: extract dst lookup parameters into a struct
====================

Link: https://patch.msgid.link/20241022092226.654370-1-steffen.klassert@secunet.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-24 11:11:33 +02:00
Jakub Sitnicki
d96016a764 udp: Compute L4 checksum as usual when not segmenting the skb
If:

  1) the user requested USO, but
  2) there is not enough payload for GSO to kick in, and
  3) the egress device doesn't offer checksum offload, then

we want to compute the L4 checksum in software early on.

In the case when we are not taking the GSO path, but it has been requested,
the software checksum fallback in skb_segment doesn't get a chance to
compute the full checksum, if the egress device can't do it. As a result we
end up sending UDP datagrams with only a partial checksum filled in, which
the peer will discard.

Fixes: 10154dbded ("udp: Allow GSO transmit from devices with no checksum offload")
Reported-by: Ivan Babrou <ivan@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20241011-uso-swcsum-fixup-v2-1-6e1ddc199af9@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15 18:12:33 -07:00
Florian Westphal
05ef7055de netfilter: fib: check correct rtable in vrf setups
We need to init l3mdev unconditionally, else main routing table is searched
and incorrect result is returned unless strict (iif keyword) matching is
requested.

Next patch adds a selftest for this.

Fixes: 2a8a7c0eaa ("netfilter: nft_fib: Fix for rpath check with VRF devices")
Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1761
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-10-09 23:30:31 +02:00
Linus Torvalds
8c245fe7dd Including fixes from ieee802154, bluetooth and netfilter.
Current release - regressions:
 
   - eth: mlx5: fix wrong reserved field in hca_cap_2 in mlx5_ifc
 
   - eth: am65-cpsw: fix forever loop in cleanup code
 
 Current release - new code bugs:
 
   - eth: mlx5: HWS, fixed double-free in error flow of creating SQ
 
 Previous releases - regressions:
 
   - core: avoid potential underflow in qdisc_pkt_len_init() with UFO
 
   - core: test for not too small csum_start in virtio_net_hdr_to_skb()
 
   - vrf: revert "vrf: remove unnecessary RCU-bh critical section"
 
   - bluetooth:
     - fix uaf in l2cap_connect
     - fix possible crash on mgmt_index_removed
 
   - dsa: improve shutdown sequence
 
   - eth: mlx5e: SHAMPO, fix overflow of hd_per_wq
 
   - eth: ip_gre: fix drops of small packets in ipgre_xmit
 
 Previous releases - always broken:
 
   - core: fix gso_features_check to check for both dev->gso_{ipv4_,}max_size
 
   - core: fix tcp fraglist segmentation after pull from frag_list
 
   - netfilter: nf_tables: prevent nf_skb_duplicated corruption
 
   - sctp: set sk_state back to CLOSED if autobind fails in sctp_listen_start
 
   - mac802154: fix potential RCU dereference issue in mac802154_scan_worker
 
   - eth: fec: restart PPS after link state change
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from ieee802154, bluetooth and netfilter.

  Current release - regressions:

   - eth: mlx5: fix wrong reserved field in hca_cap_2 in mlx5_ifc

   - eth: am65-cpsw: fix forever loop in cleanup code

  Current release - new code bugs:

   - eth: mlx5: HWS, fixed double-free in error flow of creating SQ

  Previous releases - regressions:

   - core: avoid potential underflow in qdisc_pkt_len_init() with UFO

   - core: test for not too small csum_start in virtio_net_hdr_to_skb()

   - vrf: revert "vrf: remove unnecessary RCU-bh critical section"

   - bluetooth:
       - fix uaf in l2cap_connect
       - fix possible crash on mgmt_index_removed

   - dsa: improve shutdown sequence

   - eth: mlx5e: SHAMPO, fix overflow of hd_per_wq

   - eth: ip_gre: fix drops of small packets in ipgre_xmit

  Previous releases - always broken:

   - core: fix gso_features_check to check for both
     dev->gso_{ipv4_,}max_size

   - core: fix tcp fraglist segmentation after pull from frag_list

   - netfilter: nf_tables: prevent nf_skb_duplicated corruption

   - sctp: set sk_state back to CLOSED if autobind fails in
     sctp_listen_start

   - mac802154: fix potential RCU dereference issue in
     mac802154_scan_worker

   - eth: fec: restart PPS after link state change"

* tag 'net-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (48 commits)
  sctp: set sk_state back to CLOSED if autobind fails in sctp_listen_start
  dt-bindings: net: xlnx,axi-ethernet: Add missing reg minItems
  doc: net: napi: Update documentation for napi_schedule_irqoff
  net/ncsi: Disable the ncsi work before freeing the associated structure
  net: phy: qt2025: Fix warning: unused import DeviceId
  gso: fix udp gso fraglist segmentation after pull from frag_list
  bridge: mcast: Fail MDB get request on empty entry
  vrf: revert "vrf: Remove unnecessary RCU-bh critical section"
  net: ethernet: ti: am65-cpsw: Fix forever loop in cleanup code
  net: phy: realtek: Check the index value in led_hw_control_get
  ppp: do not assume bh is held in ppp_channel_bridge_input()
  selftests: rds: move include.sh to TEST_FILES
  net: test for not too small csum_start in virtio_net_hdr_to_skb()
  net: gso: fix tcp fraglist segmentation after pull from frag_list
  ipv4: ip_gre: Fix drops of small packets in ipgre_xmit
  net: stmmac: dwmac4: extend timeout for VLAN Tag register busy bit check
  net: add more sanity checks to qdisc_pkt_len_init()
  net: avoid potential underflow in qdisc_pkt_len_init() with UFO
  net: ethernet: ti: cpsw_ale: Fix warning on some platforms
  net: microchip: Make FDMA config symbol invisible
  ...
2024-10-03 09:44:00 -07:00
Paolo Abeni
1127c73a8d netfilter pull request 24-10-02
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Merge tag 'nf-24-10-02' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf

Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for net:

1) Fix incorrect documentation in uapi/linux/netfilter/nf_tables.h
   regarding flowtable hooks, from Phil Sutter.

2) Fix nft_audit.sh selftests with newer nft binaries, due to different
   (valid) audit output, also from Phil.

3) Disable BH when duplicating packets via nf_dup infrastructure,
   otherwise race on nf_skb_duplicated for locally generated traffic.
   From Eric.

4) Missing return in callback of selftest C program, from zhang jiao.

netfilter pull request 24-10-02

* tag 'nf-24-10-02' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  selftests: netfilter: Add missing return value
  netfilter: nf_tables: prevent nf_skb_duplicated corruption
  selftests: netfilter: Fix nft_audit.sh for newer nft binaries
  netfilter: uapi: NFTA_FLOWTABLE_HOOK is NLA_NESTED
====================

Link: https://patch.msgid.link/20241002202421.1281311-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-03 12:01:05 +02:00