At some point limits were added to forward_delay. However, the
limits are only enforced when STP is enabled. This created a
scenario where you could have a value outside the allowed range
while STP is disabled, which then stuck around even after STP
is enabled.
This patch fixes this by clamping the value when we enable STP.
I had to move the locking around a bit to ensure that there is
no window where someone could insert a value outside the range
while we're in the middle of enabling STP.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cheers,
Signed-off-by: David S. Miller <davem@davemloft.net>