pfcp_encap_recv() only makes sure that the UDP header and the 4 byte
PFCP header are in the linear area. When the S flag is set,
pfcp_session_recv() then reads the 8 byte SEID that follows, which is
not covered by the pskb_may_pull() check.
A short PFCP packet with the S flag set, or one whose session header
lies in a fragment, therefore makes pfcp_session_recv() read beyond the
end of the packet data, and whatever it finds there is stored in the
tunnel metadata that flower later classifies on.
Pull up to the end of the SEID before reading it, and drop packets
that are too short to contain it. Reload the header pointer afterwards
since pskb_may_pull() may reallocate the skb head.
Use offsetofend() rather than sizeof(struct pfcphdr_session): the
structure is not packed, so its size is 16 bytes because of the
alignment of the __be64 member, while the header on the wire is only 12
bytes, and valid session messages would be dropped.
Fixes: 6dd514f481 ("pfcp: always set pfcp metadata")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Link: https://patch.msgid.link/20260930124818.114224-3-yanhaishuang@cmss.chinamobile.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pfcp_newlink() creates the UDP socket before register_netdevice().
If registration fails after pfcp_dev_init() succeeds, the core calls
pfcp_dev_uninit(), which releases the socket and clears pfcp->sk.
The newlink error path then releases it again, causing a NULL pointer
dereference. This was observed with failslab fault injection:
FAULT_INJECTION: forcing a failure.
kobject: kobject_add_internal failed for pfcp0 (error: -12 parent: net)
BUG: KASAN: null-ptr-deref in udp_tunnel_sock_release+0x1c/0x50
Read of size 8 at addr 0000000000000120 by task ip/1037
Call trace:
show_stack+0x18/0x24 (C)
dump_stack_lvl+0x78/0x90
print_report+0x468/0x5cc
kasan_report+0xa4/0xf0
__asan_load8+0x7c/0xd0
udp_tunnel_sock_release+0x1c/0x50
pfcp_newlink+0x128/0x184
rtnl_newlink+0x848/0xe44
rtnetlink_rcv_msg+0x468/0x514
netlink_rcv_skb+0xc0/0x1f0
rtnetlink_rcv+0x18/0x24
netlink_unicast+0x4b8/0x558
netlink_sendmsg+0x2b8/0x584
...
Return from pfcp_del_sock() if pfcp->sk is NULL.
Fixes: 76c8764ef3 ("pfcp: add PFCP module")
Cc: stable@vger.kernel.org
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260924055252.33488-1-xuanqiang.luo@linux.dev
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
pfcp_net_exit_rtnl() iterates pfcp devices whose sockets
are in the dying netns and queues them for destruction.
So the devices may reside in different netns.
Let's use unregister_netdevice_queue_net() to support per-netns
device unregistration.
list_del() is changed to list_del_init() to avoid queueing the
same device twice.
Even after pfcp_net_exit_rtnl() queues a cross-netns pfcp device,
pfcp_dellink() could be called concurrently for it (once RTNL is
removed). In such a case, __rtnl_net_unlock() will perform the
unregistration.
We can see pfcp0 below is unregistered by the per-netns work
instead of cleanup_net().
# bpftrace -e '#include <linux/netdevice.h>
kprobe:pfcp_dev_uninit {
$dev = (struct net_device *)arg0;
printf("PID: %d | DEV: %s%s\n", pid, $dev->name, kstack());
}
kprobe:pfcp_net_exit_rtnl {
printf("PID: %d%s\n", pid, kstack());
}' &
# ip netns add ns1
# ip netns add ns2
# ip -n ns1 link add pfcp0 link-netns ns2 type pfcp
# ip netns del ns2
PID: 12
pfcp_net_exit_rtnl+5
ops_undo_list+702
cleanup_net+1122
process_scheduled_works+2538
...
PID: 462 | DEV: pfcp0
pfcp_dev_uninit+5
unregister_netdevice_many_notify+7129
unregister_netdevice_many_net+1050
rtnl_net_work_func+136
process_scheduled_works+2538
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260731224406.2444121-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
struct pfcp_dev.net is the netns where the backend pfcp socket
resides.
struct pfcp_dev is linked to the pfcp_net.pfcp_dev_list of
the socket's netns.
During netns dismantle or module unload, pfcp_net_exit_rtnl()
iterates the list and queues devices for destruction regardless
of the devices' netns.
Thus, once RTNL is removed, the list can be modified concurrently
from different netns due to device removal.
Let's protect it with per-netns mutex.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260731224406.2444121-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge in late fixes in preparation for the net-next PR.
Conflicts:
net/tls/tls_sw.c
406e8a651a ("net: skmsg: preserve sg.copy across SG transforms")
79511603a6 ("tls: remove dead sockmap (psock) handling from the SW path")
drivers/net/ethernet/microsoft/mana/mana_en.c
f8fd56977e ("net: mana: guard TX wq object destroy with INVALID_MANA_HANDLE check")
d07efe5a6e ("net: mana: Use per-queue allocation for tx_qp to reduce allocation size")
https://lore.kernel.org/ajAPXu-C_PuTgV-a@sirena.org.uk
No adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
PFCP uses dev_get_tstats64() as its ndo_get_stats64 callback, but
pfcp_link_setup() does not request NETDEV_PCPU_STAT_TSTATS. The net
core therefore leaves dev->tstats NULL for PFCP devices.
Creating a PFCP rtnetlink device can immediately ask the new netdev for
stats while building the RTM_NEWLINK notification. That reaches
dev_get_tstats64() and dereferences the NULL dev->tstats pointer.
Set pcpu_stat_type to NETDEV_PCPU_STAT_TSTATS during PFCP link setup so
the net core allocates the storage expected by dev_get_tstats64().
Fixes: 76c8764ef3 ("pfcp: add PFCP module")
Signed-off-by: Samuel Moelius <sam.moelius@trailofbits.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20260609232244.1602027.c569f6c530f6.pfcp-missing-tstats-link-create-oops@trailofbits.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pfcp does not need to access struct socket itself in the fast
path; it only reads struct sock, and struct socket is only used
for tunnel setup and teardown.
Let's store struct sock directly in struct pfcp_dev.
pfcp_del_sock() is called from dev->netdev_ops->ndo_uninit().
The 2nd synchronize_net() in unregister_netdevice_many_notify()
ensures that inflight pfcp RX fast paths finish before pfcp_dev
is freed.
Note that synchronize_rcu() is added in the error path of
pfcp_newlink() since free_netdev() will free pfcp_dev immediately
once we remove synchronize_rcu() in udp_tunnel_sock_release().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-14-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.
Even setup_udp_tunnel_sock() does not need struct socket.
Let's change setup_udp_tunnel_sock() to take struct sock
instead of struct socket.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
None of the udp_tunnel users need struct socket in their
fast paths; it is only used for tunnel setup / teardown.
While the UDP tunnel interface accepts struct socket, this
encourages users to store the pointer unnecessarily. This
leads to extra dereferences when accessing struct sock fields
(e.g., sk->sk_user_data instead of sock->sk->sk_user_data).
Furthermore, these dereferences necessitate synchronize_rcu()
in udp_tunnel_sock_release() to protect the fast paths from
sock_orphan() setting sk->sk_socket to NULL.
This overhead can be avoided if users store the struct sock
pointer directly in their private structures.
As a prep, let's change udp_tunnel_sock_release() to take
struct sock instead of struct socket.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260502031401.3557229-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
pfcp_net_exit() holds RTNL and cleans up all devices in the netns
and other devices tied to sockets in the netns.
We can use ->exit_rtnl() to save RTNL dance for all dying netns.
Note that we delegate the for_each_netdev() part to
default_device_exit_batch() to avoid a list corruption splat
like the one reported in commit 4ccacf8649 ("gtp: Suppress
list corruption splat in gtp_net_exit_batch_rtnl().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250418003259.48017-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add two helper functions - rtnl_newlink_link_net() and
rtnl_newlink_peer_net() for netns fallback logic. Peer netns falls back
to link netns, and link netns falls back to source netns.
Convert the use of params->net in netdevice drivers to one of the helper
functions for clarity.
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250219125039.18024-4-shaw.leon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There are 4 net namespaces involved when creating links:
- source netns - where the netlink socket resides,
- target netns - where to put the device being created,
- link netns - netns associated with the device (backend),
- peer netns - netns of peer device.
Currently, two nets are passed to newlink() callback - "src_net"
parameter and "dev_net" (implicitly in net_device). They are set as
follows, depending on netlink attributes in the request.
+------------+-------------------+---------+---------+
| peer netns | IFLA_LINK_NETNSID | src_net | dev_net |
+------------+-------------------+---------+---------+
| | absent | source | target |
| absent +-------------------+---------+---------+
| | present | link | link |
+------------+-------------------+---------+---------+
| | absent | peer | target |
| present +-------------------+---------+---------+
| | present | peer | link |
+------------+-------------------+---------+---------+
When IFLA_LINK_NETNSID is present, the device is created in link netns
first and then moved to target netns. This has some side effects,
including extra ifindex allocation, ifname validation and link events.
These could be avoided if we create it in target netns from
the beginning.
On the other hand, the meaning of src_net parameter is ambiguous. It
varies depending on how parameters are passed. It is the effective
link (or peer netns) by design, but some drivers ignore it and use
dev_net instead.
To provide more netns context for drivers, this patch packs existing
newlink() parameters, along with the source netns, link netns and peer
netns, into a struct. The old "src_net" is renamed to "net" to avoid
confusion with real source netns, and will be deprecated later. The use
of src_net are converted to params->net trivially.
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250219125039.18024-3-shaw.leon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
From Arnd comments:
"The memcpy() in the ip_tunnel_info_opts_set() causes
a string.h fortification warning, with at least gcc-13:
In function 'fortify_memcpy_chk',
inlined from 'ip_tunnel_info_opts_set' at include/net/ip_tunnels.h:619:3,
inlined from 'pfcp_encap_recv' at drivers/net/pfcp.c:84:2:
include/linux/fortify-string.h:553:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
553 | __write_overflow_field(p_size_field, size);"
It is a false-positivie caused by ambiguity of the union.
However, as Arnd noticed, copying here is unescessary. The code can be
simplified to avoid calling ip_tunnel_info_opts_set(), which is doing
copying, setting flags and options_len.
Set correct flags and options_len directly on tun_info.
Fixes: 6dd514f481 ("pfcp: always set pfcp metadata")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Closes: https://lore.kernel.org/netdev/701f8f93-f5fb-408b-822a-37a1d5c424ba@app.fastmail.com/
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In PFCP receive path set metadata needed by flower code to do correct
classification based on this metadata.
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Packet Forwarding Control Protocol (PFCP) is a 3GPP Protocol
used between the control plane and the user plane function.
It is specified in TS 29.244[1].
Note that this module is not designed to support this Protocol
in the kernel space. There is no support for parsing any PFCP messages.
There is no API that could be used by any userspace daemon.
Basically it does not support PFCP. This protocol is sophisticated
and there is no need for implementing it in the kernel. The purpose
of this module is to allow users to setup software and hardware offload
of PFCP packets using tc tool.
When user requests to create a PFCP device, a new socket is created.
The socket is set up with port number 8805 which is specific for
PFCP [29.244 4.2.2]. This allow to receive PFCP request messages,
response messages use other ports.
Note that only one PFCP netdev can be created.
Only IPv4 is supported at this time.
[1] https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=3111
Signed-off-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
