kernel_samsung_a53x/include
Hangbin Liu cbf967554f ipv4/fib: send notify when delete source address routes
[ Upstream commit 4b2b606075e50cdae62ab2356b0a1e206947c354 ]

After deleting an interface address in fib_del_ifaddr(), the function
scans the fib_info list for stray entries and calls fib_flush() and
fib_table_flush(). Then the stray entries will be deleted silently and no
RTM_DELROUTE notification will be sent.

This lack of notification can make routing daemons, or monitor like
`ip monitor route` miss the routing changes. e.g.

+ ip link add dummy1 type dummy
+ ip link add dummy2 type dummy
+ ip link set dummy1 up
+ ip link set dummy2 up
+ ip addr add 192.168.5.5/24 dev dummy1
+ ip route add 7.7.7.0/24 dev dummy2 src 192.168.5.5
+ ip -4 route
7.7.7.0/24 dev dummy2 scope link src 192.168.5.5
192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5

As Ido reminded, fib_table_flush() isn't only called when an address is
deleted, but also when an interface is deleted or put down. The lack of
notification in these cases is deliberate. And commit 7c6bb7d2faaf
("net/ipv6: Add knob to skip DELROUTE message on device down") introduced
a sysctl to make IPv6 behave like IPv4 in this regard. So we can't send
the route delete notify blindly in fib_table_flush().

To fix this issue, let's add a new flag in "struct fib_info" to track the
deleted prefer source address routes, and only send notify for them.

After update:
+ ip monitor route
+ ip addr del 192.168.5.5/24 dev dummy1
Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5
Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5
Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5
Deleted 7.7.7.0/24 dev dummy2 scope link src 192.168.5.5

Suggested-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230922075508.848925-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-08 11:26:17 +01:00
..
acpi Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
asm-generic Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
clocksource Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
crypto Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
drm drm/connector: Add support for out-of-band hotplug notification (v3) 2024-11-08 11:26:15 +01:00
dt-bindings Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
keys Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
kunit Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
kvm Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
linux usb: core: Track SuperSpeed Plus GenXxY 2024-11-08 11:26:12 +01:00
math-emu Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
media Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
memory Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
misc Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
net ipv4/fib: send notify when delete source address routes 2024-11-08 11:26:17 +01:00
pcmcia Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ras Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
rdma Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
scsc Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
scsi Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
sdp Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
soc Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
sound Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
target Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
test Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
trace neighbor: tracing: Move pin6 inside CONFIG_IPV6=y section 2024-11-08 11:26:11 +01:00
uapi net: change accept_ra_min_rtr_lft to affect all RA lifetimes 2024-11-08 11:25:47 +01:00
variant1/linux Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
vdso Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
video Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xen Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00