linux/net/rfkill
Johannes Berg 54f586a915 rfkill: make new event layout opt-in
Again new complaints surfaced that we had broken the ABI here,
although previously all the userspace tools had agreed that it
was their mistake and fixed it. Yet now there are cases (e.g.
RHEL) that want to run old userspace with newer kernels, and
thus are broken.

Since this is a bit of a whack-a-mole thing, change the whole
extensibility scheme of rfkill to no longer just rely on the
message lengths, but instead require userspace to opt in via a
new ioctl to a given maximum event size that it is willing to
understand.

By default, set that to RFKILL_EVENT_SIZE_V1 (8), so that the
behaviour for userspace not calling the ioctl will look as if
it's just running on an older kernel.

Fixes: 14486c8261 ("rfkill: add a reason to the HW rfkill state")
Cc: stable@vger.kernel.org # 5.11+
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220316212749.16491491b270.Ifcb1950998330a596f29a2a162e00b7546a1d6d0@changeid
2022-03-18 13:09:17 +02:00
..
core.c rfkill: make new event layout opt-in 2022-03-18 13:09:17 +02:00
input.c rfkill: use DEFINE_SPINLOCK() for spinlock 2021-04-08 10:16:53 +02:00
Kconfig
Makefile
rfkill-gpio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1 2019-05-21 11:28:39 +02:00
rfkill.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00