twx-linux/include
Andy Ren bd039b5ea2 net/core: Allow live renaming when an interface is up
Allow a network interface to be renamed when the interface
is up.

As described in the netconsole documentation [1], when netconsole is
used as a built-in, it will bring up the specified interface as soon as
possible. As a result, user space will not be able to rename the
interface since the kernel disallows renaming of interfaces that are
administratively up unless the 'IFF_LIVE_RENAME_OK' private flag was set
by the kernel.

The original solution [2] to this problem was to add a new parameter to
the netconsole configuration parameters that allows renaming of
the interface used by netconsole while it is administratively up.
However, during the discussion that followed, it became apparent that we
have no reason to keep the current restriction and instead we should
allow user space to rename interfaces regardless of their administrative
state:

1. The restriction was put in place over 20 years ago when renaming was
only possible via IOCTL and before rtnetlink started notifying user
space about such changes like it does today.

2. The 'IFF_LIVE_RENAME_OK' flag was added over 3 years ago in version
5.2 and no regressions were reported.

3. In-kernel listeners to 'NETDEV_CHANGENAME' do not seem to care about
the administrative state of interface.

Therefore, allow user space to rename running interfaces by removing the
restriction and the associated 'IFF_LIVE_RENAME_OK' flag. Help in
possible triage by emitting a message to the kernel log that an
interface was renamed while UP.

[1] https://www.kernel.org/doc/Documentation/networking/netconsole.rst
[2] https://lore.kernel.org/netdev/20221102002420.2613004-1-andy.ren@getcruise.com/

Signed-off-by: Andy Ren <andy.ren@getcruise.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-09 13:08:12 +00:00
..
acpi ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init() 2022-10-13 20:40:09 +02:00
asm-generic asm-generic: compat: fix compat_arg_u64() and compat_arg_u64_dual() 2022-11-01 10:20:11 +11:00
clocksource
crypto
drm Merge drm/drm-fixes into drm-misc-fixes 2022-10-20 09:09:00 +02:00
dt-bindings These are the pin control changes for the v6.1 kernel cycle: 2022-10-11 10:59:59 -07:00
keys
kunit kunit: declare kunit_assert structs as const 2022-10-07 10:19:18 -06:00
kvm
linux net/core: Allow live renaming when an interface is up 2022-11-09 13:08:12 +00:00
math-emu
media media fixes for v6.1-rc2 2022-10-22 15:30:15 -07:00
memory
misc
net net: sched: add helper support in act_ct 2022-11-08 12:15:19 +01:00
pcmcia
ras
rdma
rv
scsi SCSI misc on 20221007 2022-10-07 12:33:18 -07:00
soc RISC-V Patches for the 6.1 Merge Window, Part 2 2022-10-14 11:21:11 -07:00
sound ASoC: Fixes for v6.1 2022-10-27 08:26:32 +02:00
target
trace linux-watchdog 6.1-rc2 tag 2022-10-21 12:25:39 -07:00
uapi net: sched: add helper support in act_ct 2022-11-08 12:15:19 +01:00
ufs SCSI misc on 20221007 2022-10-07 12:33:18 -07:00
vdso
video
xen xen/virtio: enable grant based virtio on x86 2022-10-10 14:31:26 +02:00