We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.

To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel)
Signed-off-by: David S. Miller <davem@davemloft.net>

Introduce a simple helper function to replace a common pattern.
When accessing the GRO header, we fetch the pointer from frag0,
then test its validity and fetch it from the skb when necessary.

This leads to the pattern
skb_gro_header_fast -> skb_gro_header_hard -> skb_gro_header_slow
recurring many times throughout GRO code.

This patch replaces these patterns with a single inlined function
call, improving code readability.

Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220823071034.GA56142@debian
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

XRFM is no longer needed for configuring FOU tunnels
(CONFIG_NET_FOU_IP_TUNNELS), remove from Kconfig.

Also remove the xrfm.h dependency in fou.c. It was
added in '23461551c006 ("fou: Support for foo-over-udp RX path")'
for depencies of udp_del_offload and udp_offloads, which were removed in
'd92283e338f6 ("fou: change to use UDP socket GRO")'.

Built and installed kernel and setup GUE/FOU tunnels.

Signed-off-by: Coco Li <lixiaoyan@google.com>
Link: https://lore.kernel.org/r/20220411213717.3688789-1-lixiaoyan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

All gro_complete() handlers are called from napi_gro_complete()
while rcu_read_lock() has been called.

There is no point stacking more rcu_read_lock()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

All gro_receive() handlers are called from dev_gro_receive()
while rcu_read_lock() has been called.

There is no point stacking more rcu_read_lock()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/linux/netdevice.h became too big, move gro stuff
into include/net/gro.h

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We need to add __rcu qualifier to avoid these errors:

net/ipv4/fou.c:250:18: warning: incorrect type in assignment (different address spaces)
net/ipv4/fou.c:250:18:    expected struct net_offload const **offloads
net/ipv4/fou.c:250:18:    got struct net_offload const [noderef] __rcu **
net/ipv4/fou.c:251:15: error: incompatible types in comparison expression (different address spaces):
net/ipv4/fou.c:251:15:    struct net_offload const [noderef] __rcu *
net/ipv4/fou.c:251:15:    struct net_offload const *
net/ipv4/fou.c:272:18: warning: incorrect type in assignment (different address spaces)
net/ipv4/fou.c:272:18:    expected struct net_offload const **offloads
net/ipv4/fou.c:272:18:    got struct net_offload const [noderef] __rcu **
net/ipv4/fou.c:273:15: error: incompatible types in comparison expression (different address spaces):
net/ipv4/fou.c:273:15:    struct net_offload const [noderef] __rcu *
net/ipv4/fou.c:273:15:    struct net_offload const *
net/ipv4/fou.c:442:18: warning: incorrect type in assignment (different address spaces)
net/ipv4/fou.c:442:18:    expected struct net_offload const **offloads
net/ipv4/fou.c:442:18:    got struct net_offload const [noderef] __rcu **
net/ipv4/fou.c:443:15: error: incompatible types in comparison expression (different address spaces):
net/ipv4/fou.c:443:15:    struct net_offload const [noderef] __rcu *
net/ipv4/fou.c:443:15:    struct net_offload const *
net/ipv4/fou.c:489:18: warning: incorrect type in assignment (different address spaces)
net/ipv4/fou.c:489:18:    expected struct net_offload const **offloads
net/ipv4/fou.c:489:18:    got struct net_offload const [noderef] __rcu **
net/ipv4/fou.c:490:15: error: incompatible types in comparison expression (different address spaces):
net/ipv4/fou.c:490:15:    struct net_offload const [noderef] __rcu *
net/ipv4/fou.c:490:15:    struct net_offload const *
net/ipv4/udp_offload.c:170:26: warning: incorrect type in assignment (different address spaces)
net/ipv4/udp_offload.c:170:26:    expected struct net_offload const **offloads
net/ipv4/udp_offload.c:170:26:    got struct net_offload const [noderef] __rcu **
net/ipv4/udp_offload.c:171:23: error: incompatible types in comparison expression (different address spaces):
net/ipv4/udp_offload.c:171:23:    struct net_offload const [noderef] __rcu *
net/ipv4/udp_offload.c:171:23:    struct net_offload const *

Fixes: efc98d08e1ec ("fou: eliminate IPv4,v6 specific GRO functions")
Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Drop duplicate words in comments in net/ipv4/.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The user tool modinfo is used to get information on kernel modules, including a
description where it is available.

This patch adds a brief MODULE_DESCRIPTION to the following modules:

9p
drop_monitor
esp4_offload
esp6_offload
fou
fou6
ila
sch_fq
sch_fq_codel
sch_hhf

Signed-off-by: Rob Gill <rrobgill@protonmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>