net/mlx5e: Lag, Don't skip fib events on current dst

Referenced change added check to skip updating fib when new fib instance
has same or lower priority. However, new fib instance can be an update on
same dst address as existing one even though the structure is another
instance that has different address. Ignoring events on such instances
causes multipath LAG state to not be correctly updated.

Track 'dst' and 'dst_len' fields of fib event fib_entry_notifier_info
structure and don't skip events that have the same value of that fields.

Fixes: ad11c4f1d8fd ("net/mlx5e: Lag, Only handle events from highest priority multipath entry")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Lag, Fix use-after-free in fib event handler

Recent commit that modified fib route event handler to handle events
according to their priority introduced use-after-free[0] in mp->mfi pointer
usage. The pointer now is not just cached in order to be compared to
following fib_info instances, but is also dereferenced to obtain
fib_priority. However, since mlx5 lag code doesn't hold the reference to
fin_info during whole mp->mfi lifetime, it could be used after fib_info
instance has already been freed be kernel infrastructure code.

Don't ever dereference mp->mfi pointer. Refactor it to be 'const void*'
type and cache fib_info priority in dedicated integer. Group
fib_info-related data into dedicated 'fib' structure that will be further
extended by following patches in the series.

[0]:

[ 203.588029] ==================================================================
[ 203.590161] BUG: KASAN: use-after-free in mlx5_lag_fib_update+0xabd/0xd60 [mlx5_core]
[ 203.592386] Read of size 4 at addr ffff888144df2050 by task kworker/u20:4/138

[ 203.594766] CPU: 3 PID: 138 Comm: kworker/u20:4 Tainted: G B 5.17.0-rc7+ #6
[ 203.596751] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[ 203.598813] Workqueue: mlx5_lag_mp mlx5_lag_fib_update [mlx5_core]
[ 203.600053] Call Trace:
[ 203.600608] <TASK>
[ 203.601110] dump_stack_lvl+0x48/0x5e
[ 203.601860] print_address_description.constprop.0+0x1f/0x160
[ 203.602950] ? mlx5_lag_fib_update+0xabd/0xd60 [mlx5_core]
[ 203.604073] ? mlx5_lag_fib_update+0xabd/0xd60 [mlx5_core]
[ 203.605177] kasan_report.cold+0x83/0xdf
[ 203.605969] ? mlx5_lag_fib_update+0xabd/0xd60 [mlx5_core]
[ 203.607102] mlx5_lag_fib_update+0xabd/0xd60 [mlx5_core]
[ 203.608199] ? mlx5_lag_init_fib_work+0x1c0/0x1c0 [mlx5_core]
[ 203.609382] ? read_word_at_a_time+0xe/0x20
[ 203.610463] ? strscpy+0xa0/0x2a0
[ 203.611463] process_one_work+0x722/0x1270
[ 203.612344] worker_thread+0x540/0x11e0
[ 203.613136] ? rescuer_thread+0xd50/0xd50
[ 203.613949] kthread+0x26e/0x300
[ 203.614627] ? kthread_complete_and_exit+0x20/0x20
[ 203.615542] ret_from_fork+0x1f/0x30
[ 203.616273] </TASK>

[ 203.617174] Allocated by task 3746:
[ 203.617874] kasan_save_stack+0x1e/0x40
[ 203.618644] __kasan_kmalloc+0x81/0xa0
[ 203.619394] fib_create_info+0xb41/0x3c50
[ 203.620213] fib_table_insert+0x190/0x1ff0
[ 203.621020] fib_magic.isra.0+0x246/0x2e0
[ 203.621803] fib_add_ifaddr+0x19f/0x670
[ 203.622563] fib_inetaddr_event+0x13f/0x270
[ 203.623377] blocking_notifier_call_chain+0xd4/0x130
[ 203.624355] __inet_insert_ifa+0x641/0xb20
[ 203.625185] inet_rtm_newaddr+0xc3d/0x16a0
[ 203.626009] rtnetlink_rcv_msg+0x309/0x880
[ 203.626826] netlink_rcv_skb+0x11d/0x340
[ 203.627626] netlink_unicast+0x4cc/0x790
[ 203.628430] netlink_sendmsg+0x762/0xc00
[ 203.629230] sock_sendmsg+0xb2/0xe0
[ 203.629955] ____sys_sendmsg+0x58a/0x770
[ 203.630756] ___sys_sendmsg+0xd8/0x160
[ 203.631523] __sys_sendmsg+0xb7/0x140
[ 203.632294] do_syscall_64+0x35/0x80
[ 203.633045] entry_SYSCALL_64_after_hwframe+0x44/0xae

[ 203.634427] Freed by task 0:
[ 203.635063] kasan_save_stack+0x1e/0x40
[ 203.635844] kasan_set_track+0x21/0x30
[ 203.636618] kasan_set_free_info+0x20/0x30
[ 203.637450] __kasan_slab_free+0xfc/0x140
[ 203.638271] kfree+0x94/0x3b0
[ 203.638903] rcu_core+0x5e4/0x1990
[ 203.639640] __do_softirq+0x1ba/0x5d3

[ 203.640828] Last potentially related work creation:
[ 203.641785] kasan_save_stack+0x1e/0x40
[ 203.642571] __kasan_record_aux_stack+0x9f/0xb0
[ 203.643478] call_rcu+0x88/0x9c0
[ 203.644178] fib_release_info+0x539/0x750
[ 203.644997] fib_table_delete+0x659/0xb80
[ 203.645809] fib_magic.isra.0+0x1a3/0x2e0
[ 203.646617] fib_del_ifaddr+0x93f/0x1300
[ 203.647415] fib_inetaddr_event+0x9f/0x270
[ 203.648251] blocking_notifier_call_chain+0xd4/0x130
[ 203.649225] __inet_del_ifa+0x474/0xc10
[ 203.650016] devinet_ioctl+0x781/0x17f0
[ 203.650788] inet_ioctl+0x1ad/0x290
[ 203.651533] sock_do_ioctl+0xce/0x1c0
[ 203.652315] sock_ioctl+0x27b/0x4f0
[ 203.653058] __x64_sys_ioctl+0x124/0x190
[ 203.653850] do_syscall_64+0x35/0x80
[ 203.654608] entry_SYSCALL_64_after_hwframe+0x44/0xae

[ 203.666952] The buggy address belongs to the object at ffff888144df2000
which belongs to the cache kmalloc-256 of size 256
[ 203.669250] The buggy address is located 80 bytes inside of
256-byte region [ffff888144df2000, ffff888144df2100)
[ 203.671332] The buggy address belongs to the page:
[ 203.672273] page:00000000bf6c9314 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x144df0
[ 203.674009] head:00000000bf6c9314 order:2 compound_mapcount:0 compound_pincount:0
[ 203.675422] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff)
[ 203.676819] raw: 002ffff800010200 0000000000000000 dead000000000122 ffff888100042b40
[ 203.678384] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 203.679928] page dumped because: kasan: bad access detected

[ 203.681455] Memory state around the buggy address:
[ 203.682421] ffff888144df1f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 203.683863] ffff888144df1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 203.685310] >ffff888144df2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 203.686701] ^
[ 203.687820] ffff888144df2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 203.689226] ffff888144df2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 203.690620] ==================================================================

Fixes: ad11c4f1d8fd ("net/mlx5e: Lag, Only handle events from highest priority multipath entry")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Lag, Make mlx5_lag_is_multipath() be static inline

Fix "no previous prototype" W=1 warnings when CONFIG_MLX5_CORE_EN is not set:

drivers/net/ethernet/mellanox/mlx5/core/lag_mp.h:34:6: error: no previous prototype for ‘mlx5_lag_is_multipath’ [-Werror=missing-prototypes]
34 | bool mlx5_lag_is_multipath(struct mlx5_core_dev *dev) { return false; }
| ^~~~~~~~~~~~~~~~~~~~~

Fixes: 14fe2471c628 ("net/mlx5: Lag, change multipath and bonding to be mutually exclusive")
Signed-off-by: Maor Dickman <maord@nvidia.com>

net/mlx5: Lag, move lag files into directory

Downstream patches add another lag related file so it makes
sense to have all the lag files in a dedicated directory.

Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>