ipv6: release rt6->rt6i_idev properly during ifdown
When a dst is created by addrconf_dst_alloc() for a host route or an
anycast route, dst->dev points to loopback dev while rt6->rt6i_idev
points to a real device.
When the real device goes down, the current cleanup code only checks for
dst->dev and assumes rt6->rt6i_idev->dev is the same. This causes the
refcount leak on the real device in the above situation.
This patch makes sure to always release the refcount taken on
rt6->rt6i_idev during dst_dev_put().
Fixes: 587fea741134 ("ipv6: mark DST_NOGC and remove the operation of
dst_free()")
Reported-by: John Stultz <john.stultz at linaro.org>
Tested-by: John Stultz <john.stultz at linaro.org>
Tested-by: Martin KaFai Lau <kafai at fb.com>
Signed-off-by: Wei Wang <weiwan at google.com>
Signed-off-by: Martin KaFai Lau <kafai at fb.com>
Acked-by: David Ahern <dsahern at gmail.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
UnifiedSplitRaw
