ptp: netc: skip PEROUT disable if channel is not enabled

When userspace calls ioctl(PTP_PEROUT_REQUEST) with period = 0 to disable
a PEROUT channel that is not enabled, the driver incorrectly enters the
disable path. Since the channel's struct netc_pp was previously zeroed,
pp->alarm_id evaluates to 0, causing priv->fs_alarm_bitmap &= ~BIT(0) to
silently revoke the alarm 0 allocation from whichever channel is actively
using it. This can cause two channels conflict over the same hardware
alarm configuration and corrupt their periodic output signals.

Therefore, guard the disable path with a check on pp->enabled and return
early if the channel is not enabled.

Fixes: 671e266835b8 ("ptp: netc: add periodic pulse output support")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/message/20260809031908.46EBF1F00A3A%40smtp.kernel.org
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20260811083614.3589967-1-wei.fang@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions