vxlan: vnifilter: Use GFP_KERNEL instead of GFP_ATOMIC

The function is not called from an atomic context so use GFP_KERNEL
instead of GFP_ATOMIC. The allocation of the per-CPU stats is already
performed with GFP_KERNEL.

Tested using test_vxlan_vnifiltering.sh with CONFIG_DEBUG_ATOMIC_SLEEP.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230821141923.1889776-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers: vxlan: vnifilter: free percpu vni stats on error path

In case rhashtable_lookup_insert_fast() fails inside vxlan_vni_add(), the
allocated percpu vni stats are not freed on the error path.

Introduce vxlan_vni_free() which would work as a nice wrapper to free
vxlan_vni_node resources properly.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 4095e0e1328a ("drivers: vxlan: vnifilter: per vni stats")
Suggested-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove the obsolte u64_stats_fetch_*_irq() users (drivers).

Now that the 32bit UP oddity is gone and 32bit uses always a sequence
count, there is no need for the fetch_irq() variants anymore.

Convert to the regular interface.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

vxlan: do not feed vxlan_vnifilter_dump_dev with non vxlan devices

vxlan_vnifilter_dump_dev() assumes it is called only
for vxlan devices. Make sure it is the case.

BUG: KASAN: slab-out-of-bounds in vxlan_vnifilter_dump_dev+0x9a0/0xb40 drivers/net/vxlan/vxlan_vnifilter.c:349
Read of size 4 at addr ffff888060d1ce70 by task syz-executor.3/17662

CPU: 0 PID: 17662 Comm: syz-executor.3 Tainted: G W 5.17.0-syzkaller-12888-g77c9387c0c5b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313
print_report mm/kasan/report.c:429 [inline]
kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
vxlan_vnifilter_dump_dev+0x9a0/0xb40 drivers/net/vxlan/vxlan_vnifilter.c:349
vxlan_vnifilter_dump+0x3ff/0x650 drivers/net/vxlan/vxlan_vnifilter.c:428
netlink_dump+0x4b5/0xb70 net/netlink/af_netlink.c:2270
__netlink_dump_start+0x647/0x900 net/netlink/af_netlink.c:2375
netlink_dump_start include/linux/netlink.h:245 [inline]
rtnetlink_rcv_msg+0x70c/0xb80 net/core/rtnetlink.c:5953
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:705 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:725
____sys_sendmsg+0x6e2/0x800 net/socket.c:2413
___sys_sendmsg+0xf3/0x170 net/socket.c:2467
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f87b8e89049

Fixes: f9c4bb0b245c ("vxlan: vni filtering support on collect metadata device")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Link: https://lore.kernel.org/r/20220330194643.2706132-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers: vxlan: vnifilter: add support for stats dumping

Add support for VXLAN vni filter entries' stats dumping

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers: vxlan: vnifilter: per vni stats

Add per-vni statistics for vni filter mode. Counting Rx/Tx
bytes/packets/drops/errors at the appropriate places.

This patch changes vxlan_vs_find_vni to also return the
vxlan_vni_node in cases where the vni belongs to a vni
filtering vxlan device

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vxlan: vni filtering support on collect metadata device

This patch adds vnifiltering support to collect metadata device.

Motivation:
You can only use a single vxlan collect metadata device for a given
vxlan udp port in the system today. The vxlan collect metadata device
terminates all received vxlan packets. As shown in the below diagram,
there are use-cases where you need to support multiple such vxlan devices in
independent bridge domains. Each vxlan device must terminate the vni's
it is configured for.
Example usecase: In a service provider network a service provider
typically supports multiple bridge domains with overlapping vlans.
One bridge domain per customer. Vlans in each bridge domain are
mapped to globally unique vxlan ranges assigned to each customer.

vnifiltering support in collect metadata devices terminates only configured
vnis. This is similar to vlan filtering in bridge driver. The vni filtering
capability is provided by a new flag on collect metadata device.

In the below pic:
- customer1 is mapped to br1 bridge domain
- customer2 is mapped to br2 bridge domain
- customer1 vlan 10-11 is mapped to vni 1001-1002
- customer2 vlan 10-11 is mapped to vni 2001-2002
- br1 and br2 are vlan filtering bridges
- vxlan1 and vxlan2 are collect metadata devices with
vnifiltering enabled

┌──────────────────────────────────────────────────────────────────┐
│ switch │
│ │
│ ┌───────────┐ ┌───────────┐ │
│ │ │ │ │ │
│ │ br1 │ │ br2 │ │
│ └┬─────────┬┘ └──┬───────┬┘ │
│ vlans│ │ vlans │ │ │
│ 10,11│ │ 10,11│ │ │
│ │ vlanvnimap: │ vlanvnimap: │
│ │ 10-1001,11-1002 │ 10-2001,11-2002 │
│ │ │ │ │ │
│ ┌──────┴┐ ┌──┴─────────┐ ┌───┴────┐ │ │
│ │ swp1 │ │vxlan1 │ │ swp2 │ ┌┴─────────────┐ │
│ │ │ │ vnifilter:│ │ │ │vxlan2 │ │
│ └───┬───┘ │ 1001,1002│ └───┬────┘ │ vnifilter: │ │
│ │ └────────────┘ │ │ 2001,2002 │ │
│ │ │ └──────────────┘ │
│ │ │ │
└───────┼──────────────────────────────────┼───────────────────────┘
│ │
│ │
┌─────┴───────┐ │
│ customer1 │ ┌─────┴──────┐
│ host/VM │ │customer2 │
└─────────────┘ │ host/VM │
└────────────┘

With this implementation, vxlan dst metadata device can
be associated with range of vnis.
struct vxlan_vni_node is introduced to represent
a configured vni. We start with vni and its
associated remote_ip in this structure. This
structure can be extended to bring in other
per vni attributes if there are usecases for it.
A vni inherits an attribute from the base vxlan device
if there is no per vni attributes defined.

struct vxlan_dev gets a new rhashtable for
vnis called vxlan_vni_group. vxlan_vnifilter.c
implements the necessary netlink api, notifications
and helper functions to process and manage lifecycle
of vxlan_vni_node.

This patch also adds new helper functions in vxlan_multicast.c
to handle per vni remote_ip multicast groups which are part
of vxlan_vni_group.

Fix build problems:
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>