linux-stable.git/net/l2tp, branch linux-6.9.y

inet: introduce dst_rtable() helper

2024-06-12T09:39:55+00:00

[ Upstream commit 05d6d492097c55f2d153fc3fd33cbe78e1e28e0a ]

I added dst_rt6_info() in commit
e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper")

This patch does a similar change for IPv4.

Instead of (struct rtable *)dst casts, we can use :

 #define dst_rtable(_ptr) \
             container_of_const(_ptr, struct rtable, dst)

Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper.

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Reviewed-by: Sabrina Dubroca 
Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Stable-dep-of: 92f1655aa2b2 ("net: fix __dst_negative_advice() race")
Signed-off-by: Sasha Levin

ipv6: introduce dst_rt6_info() helper

2024-06-12T09:39:54+00:00

[ Upstream commit e8dfd42c17faf183415323db1ef0c977be0d6489 ]

Instead of (struct rt6_info *)dst casts, we can use :

 #define dst_rt6_info(_ptr) \
         container_of_const(_ptr, struct rt6_info, dst)

Some places needed missing const qualifiers :

ip6_confirm_neigh(), ipv6_anycast_destination(),
ipv6_unicast_destination(), has_gateway()

v2: added missing parts (David Ahern)

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Stable-dep-of: 92f1655aa2b2 ("net: fix __dst_negative_advice() race")
Signed-off-by: Sasha Levin

l2tp: fix ICMP error handling for UDP-encap sockets

2024-05-30T07:45:04+00:00

[ Upstream commit 6e828dc60e509b79ef09882264952f341cb58425 ]

Since commit a36e185e8c85
("udp: Handle ICMP errors for tunnels with same destination port on both endpoints")
UDP's handling of ICMP errors has allowed for UDP-encap tunnels to
determine socket associations in scenarios where the UDP hash lookup
could not.

Subsequently, commit d26796ae58940
("udp: check udp sock encap_type in __udp_lib_err")
subtly tweaked the approach such that UDP ICMP error handling would be
skipped for any UDP socket which has encapsulation enabled.

In the case of L2TP tunnel sockets using UDP-encap, this latter
modification effectively broke ICMP error reporting for the L2TP
control plane.

To a degree this isn't catastrophic inasmuch as the L2TP control
protocol defines a reliable transport on top of the underlying packet
switching network which will eventually detect errors and time out.

However, paying attention to the ICMP error reporting allows for more
timely detection of errors in L2TP userspace, and aids in debugging
connectivity issues.

Reinstate ICMP error handling for UDP encap L2TP tunnels:

 * implement struct udp_tunnel_sock_cfg .encap_err_rcv in order to allow
   the L2TP code to handle ICMP errors;

 * only implement error-handling for tunnels which have a managed
   socket: unmanaged tunnels using a kernel socket have no userspace to
   report errors back to;

 * flag the error on the socket, which allows for userspace to get an
   error such as -ECONNREFUSED back from sendmsg/recvmsg;

 * pass the error into ip[v6]_icmp_error() which allows for userspace to
   get extended error information via. MSG_ERRQUEUE.

Fixes: d26796ae5894 ("udp: check udp sock encap_type in __udp_lib_err")
Signed-off-by: Tom Parkin 
Link: https://lore.kernel.org/r/20240513172248.623261-1-tparkin@katalix.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net l2tp: drop flow hash on forward

2024-04-26T11:48:24+00:00

Drop the flow-hash of the skb when forwarding to the L2TP netdev.

This avoids the L2TP qdisc from using the flow-hash from the outer
packet, which is identical for every flow within the tunnel.

This does not affect every platform but is specific for the ethernet
driver. It depends on the platform including L4 information in the
flow-hash.

One such example is the Mediatek Filogic MT798x family of networking
processors.

Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support")
Acked-by: James Chapman 
Signed-off-by: David Bauer 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20240424171110.13701-1-mail@david-bauer.net
Signed-off-by: Paolo Abeni

l2tp: fix incorrect parameter validation in the pppol2tp_getsockopt() function

2024-03-11T09:53:22+00:00

The 'len' variable can't be negative when assigned the result of
'min_t' because all 'min_t' parameters are cast to unsigned int,
and then the minimum one is chosen.

To fix the logic, check 'len' as read from 'optlen',
where the types of relevant variables are (signed) int.

Fixes: 3557baabf280 ("[L2TP]: PPP over L2TP driver core")
Reviewed-by: Tom Parkin 
Signed-off-by: Gavrilov Ilia 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2024-02-22T23:29:26+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

net/ipv4/udp.c
  f796feabb9f5 ("udp: add local "peek offset enabled" flag")
  56667da7399e ("net: implement lockless setsockopt(SO_PEEK_OFF)")

Adjacent changes:

net/unix/garbage.c
  aa82ac51d633 ("af_unix: Drop oob_skb ref before purging queue in GC.")
  11498715f266 ("af_unix: Remove io_uring code for GC.")

Signed-off-by: Jakub Kicinski

l2tp: pass correct message length to ip6_append_data

2024-02-22T09:42:17+00:00

l2tp_ip6_sendmsg needs to avoid accounting for the transport header
twice when splicing more data into an already partially-occupied skbuff.

To manage this, we check whether the skbuff contains data using
skb_queue_empty when deciding how much data to append using
ip6_append_data.

However, the code which performed the calculation was incorrect:

     ulen = len + skb_queue_empty(&sk->sk_write_queue) ? transhdrlen : 0;

...due to C operator precedence, this ends up setting ulen to
transhdrlen for messages with a non-zero length, which results in
corrupted packets on the wire.

Add parentheses to correct the calculation in line with the original
intent.

Fixes: 9d4c75800f61 ("ipv4, ipv6: Fix handling of transhdrlen in __ip{,6}_append_data()")
Cc: David Howells 
Cc: stable@vger.kernel.org
Signed-off-by: Tom Parkin 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20240220122156.43131-1-tparkin@katalix.com
Signed-off-by: Paolo Abeni

net: l2tp: constify the struct device_type usage

2024-02-21T09:45:23+00:00

Since commit aed65af1cc2f ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the l2tpeth_type
variable to be a constant structure as well, placing it into read-only
memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman 
Signed-off-by: Ricardo B. Marliere 
Reviewed-by: Guillaume Nault 
Signed-off-by: David S. Miller

ipv4: Set the routing scope properly in ip_route_output_ports().

2024-02-13T01:33:05+00:00

Set scope automatically in ip_route_output_ports() (using the socket
SOCK_LOCALROUTE flag). This way, callers don't have to overload the
tos with the RTO_ONLINK flag, like RT_CONN_FLAGS() does.

For callers that don't pass a struct sock, this doesn't change anything
as the scope is still set to RT_SCOPE_UNIVERSE when sk is NULL.

Callers that passed a struct sock and used RT_CONN_FLAGS(sk) or
RT_CONN_FLAGS_TOS(sk, tos) for the tos are modified to use
ip_sock_tos(sk) and RT_TOS(tos) respectively, as overloading tos with
the RTO_ONLINK flag now becomes unnecessary.

In drivers/net/amt.c, all ip_route_output_ports() calls use a 0 tos
parameter, ignoring the SOCK_LOCALROUTE flag of the socket. But the sk
parameter is a kernel socket, which doesn't have any configuration path
for setting SOCK_LOCALROUTE anyway. Therefore, ip_route_output_ports()
will continue to initialise scope with RT_SCOPE_UNIVERSE and amt.c
doesn't need to be modified.

Also, remove RT_CONN_FLAGS() and RT_CONN_FLAGS_TOS() from route.h as
these macros are now unused.

The objective is to eventually remove RTO_ONLINK entirely to allow
converting ->flowi4_tos to dscp_t. This will ensure proper isolation
between the DSCP and ECN bits, thus minimising the risk of introducing
bugs where TOS values interfere with ECN.

Signed-off-by: Guillaume Nault 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/dacfd2ab40685e20959ab7b53c427595ba229e7d.1707496938.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski

ipv6: annotate data-races around np->ucast_oif

2023-12-11T10:59:17+00:00

np->ucast_oif is read locklessly in some contexts.

Make all accesses to this field lockless, adding appropriate
annotations.

This also makes setsockopt( IPV6_UNICAST_IF ) lockless.

Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller